diff --git a/robot_assets/workflow/urdf_to_mjcf.py b/robot_assets/workflow/urdf_to_mjcf.py
index 8fe08fc..a9dc34d 100644
--- a/robot_assets/workflow/urdf_to_mjcf.py
+++ b/robot_assets/workflow/urdf_to_mjcf.py
@@ -4,7 +4,7 @@
   raw URDF + meshes  ->  MuJoCo compile  ->  post-process:
     * replace cylinder geoms with capsules
     * inject <option> physics tuning (from cad/physics.json)
-    * synthesize <motor> actuators (forcerange from joint_properties effort_limit;
+    * synthesize <position> actuators (forcerange from joint_properties effort_limit;
       no <sensor> block -- see add_actuators)
     * set per-joint frictionloss / armature (from joint_properties)
   ->  mjcf/<robot>.xml  (meshdir -> ../meshes/visual/)
@@ -158,7 +158,27 @@ def format_motor_forcerange_from_effort_limit(effort_limit) -> str:
 
 
 def add_actuators(xml_file_path: Path, joint_properties: dict) -> None:
-    """Synthesize one <motor> actuator per actuated joint. Emits no <sensor> block.
+    """Synthesize one <position> actuator per actuated joint. Emits no <sensor> block.
+
+    <position> rather than <motor> because the joint-level PD belongs INSIDE the
+    physics step: MuJoCo evaluates actuators every ``mj_step``, which mirrors the
+    real RobStride drive closing its onboard loop at ~1 kHz independently of the
+    host rate, and lets ``implicitfast`` integrate the damping term implicitly (the
+    reason a stiff PD stays stable at a coarse timestep, and how mjlab trains).
+    A <motor> instead makes ``ctrl`` a raw torque, which forces the host to sample
+    the PD once per controller_manager tick.
+
+    ``kp``/``kv`` are deliberately left at MuJoCo's defaults: the operative gains
+    are mode-dependent (standby, policy, damping all differ) and arrive over
+    ros2_control's stiffness/damping command interfaces, so MujocoSystem overwrites
+    ``actuator_gainprm``/``actuator_biasprm`` every tick. Values baked here would
+    only mislead.
+
+    NO ``ctrlrange``/``ctrllimited`` is emitted, and that is load-bearing: an RL
+    policy is allowed to command a position setpoint BEYOND the mechanical joint
+    limit in order to hold a saturating torque, so clamping the setpoint would
+    silently cap the achievable torque. ``forcerange`` still bounds the output,
+    which is the limit that is physically real.
 
     jointpos/jointvel sensors are intentionally omitted. They are redundant with
     mjData.qpos/qvel -- mjlab reads joint state from the Entity/Articulation data,
@@ -185,12 +205,12 @@ def add_actuators(xml_file_path: Path, joint_properties: dict) -> None:
     actuator_section = ensure_section(root, "actuator")
 
     for joint_name in joints:
-        motor = ET.SubElement(actuator_section, "motor")
-        motor.set("name", joint_name)
-        motor.set("joint", joint_name)
+        actuator = ET.SubElement(actuator_section, "position")
+        actuator.set("name", joint_name)
+        actuator.set("joint", joint_name)
         joint_config = resolve_joint_properties(joint_name, joint_properties)
         effort_limit = require_joint_attribute(joint_name, joint_config, "effort_limit")
-        motor.set("forcerange", format_motor_forcerange_from_effort_limit(effort_limit))
+        actuator.set("forcerange", format_motor_forcerange_from_effort_limit(effort_limit))
 
     tree.write(xml_file_path, encoding="utf-8", xml_declaration=True)
 
diff --git a/robot_assets/workflow/urdf_to_xacro.py b/robot_assets/workflow/urdf_to_xacro.py
index 835d70c..65c963f 100644
--- a/robot_assets/workflow/urdf_to_xacro.py
+++ b/robot_assets/workflow/urdf_to_xacro.py
@@ -77,15 +77,44 @@ def build_description_xacro(
 # ---------------------------------------------------------------------------
 
 
-def _joint_macro(robot: str, command: list[str], state: list[str]) -> str:
+_LINKAGE_PARAM_BLOCK = """        <!-- Four-bar transmission geometry, for joints that declare one in
+             ros2_control.json. The geometry is a PHYSICAL FACT so it is always
+             published: calibrate_robot reads it from /robot_description to refer
+             the URDF joint limits into actuator space, even on the runs where the
+             hardware plugin must NOT apply the transform. `linkage_enabled`
+             (= the use_linkage arg) is what switches the plugin's behaviour:
+             false during calibration, which needs raw actuator angles. With it
+             true, RobstrideSystem converts joint<->actuator through the linkage
+             and refers the commanded impedance by J^2, so /joint_states and every
+             controller speak true joint space. -->
+        <xacro:if value="${linkage_ground > 0}">
+          <param name="linkage_ground">${linkage_ground}</param>
+          <param name="linkage_crank_in">${linkage_crank_in}</param>
+          <param name="linkage_coupler">${linkage_coupler}</param>
+          <param name="linkage_crank_out">${linkage_crank_out}</param>
+          <param name="linkage_alpha_zero">${linkage_alpha_zero}</param>
+          <param name="linkage_sign">${linkage_sign}</param>
+          <param name="linkage_enabled">${use_linkage}</param>
+        </xacro:if>
+"""
+
+def _joint_macro(robot: str, command: list[str], state: list[str],
+                 any_linkage: bool = False) -> str:
     cmd_lines = "\n".join(f'      <command_interface name="{n}"/>' for n in command)
     state_lines = "\n".join(f'      <state_interface name="{n}"/>' for n in state)
+    # The four-bar params/section only appear for robots that declare a linkage,
+    # so every other robot regenerates byte-identically.
+    link_params = ("""
+                       use_linkage:=true linkage_ground:=0
+                       linkage_crank_in:=0 linkage_coupler:=0 linkage_crank_out:=0
+                       linkage_alpha_zero:=0 linkage_sign:=1""" if any_linkage else "")
+    link_block = _LINKAGE_PARAM_BLOCK if any_linkage else ""
     return f"""  <!-- One joint: {len(command)} command + {len(state)} state interfaces (MIT mode).
        Real-only hardware params are emitted under xacro:unless (sim/mock ignore them). -->
   <xacro:macro name="{robot}_joint"
                params="name can_id model direction
                        lower_limit upper_limit torque_limit current_limit
-                       use_fake_hardware use_sim">
+                       use_fake_hardware use_sim{link_params}">
     <joint name="${{name}}">
 {cmd_lines}
 {state_lines}
@@ -97,15 +126,38 @@ def _joint_macro(robot: str, command: list[str], state: list[str]) -> str:
         <param name="upper_limit">${{upper_limit}}</param>
         <param name="torque_limit">${{torque_limit}}</param>
         <param name="current_limit">${{current_limit}}</param>
-      </xacro:unless>
+{link_block}      </xacro:unless>
     </joint>
   </xacro:macro>"""
 
 
+#: Four-bar transmission keys a joint may declare under ``linkage`` in
+#: ros2_control.json. Lengths must share one unit; ``alpha_zero`` is in DEGREES.
+_LINKAGE_KEYS = ("ground", "crank_in", "coupler", "crank_out", "alpha_zero", "sign")
+
+
 def _joint_call(robot: str, joint: dict, limits: dict) -> str:
     limit = limits.get(joint["name"], {})
     lower = limit.get("lower", 0.0)
     upper = limit.get("upper", 0.0)
+    linkage = joint.get("linkage")
+    extra = ""
+    if linkage:
+        missing = [k for k in _LINKAGE_KEYS[:4] if k not in linkage]
+        if missing:
+            raise ValueError(
+                f'joint {joint["name"]!r}: linkage missing {missing}; all four '
+                f"lengths (ground/crank_in/coupler/crank_out) are required."
+            )
+        extra = (
+            f'\n                      linkage_ground="{linkage["ground"]}" '
+            f'linkage_crank_in="{linkage["crank_in"]}"\n'
+            f'                      linkage_coupler="{linkage["coupler"]}" '
+            f'linkage_crank_out="{linkage["crank_out"]}"\n'
+            f'                      linkage_alpha_zero="{linkage.get("alpha_zero", 0)}" '
+            f'linkage_sign="{linkage.get("sign", 1)}"'
+            f'\n                      use_linkage="${{use_linkage}}"'
+        )
     return (
         f'    <xacro:{robot}_joint name="{joint["name"]}" can_id="{joint["can_id"]}" '
         f'model="{joint["model"]}" direction="{joint["direction"]}"\n'
@@ -113,7 +165,7 @@ def _joint_call(robot: str, joint: dict, limits: dict) -> str:
         f'                      torque_limit="{joint["torque_limit"]}" '
         f'current_limit="{joint["current_limit"]}"\n'
         f'                      use_fake_hardware="${{use_fake_hardware}}" '
-        f'use_sim="${{use_sim}}"/>'
+        f'use_sim="${{use_sim}}"{extra}/>'
     )
 
 
@@ -124,7 +176,10 @@ def _group_macro(robot: str, group: str, joints: list[dict], limits: dict) -> st
     <!-- TODO: {group} joint declarations land here. -->
   </xacro:macro>"""
     calls = "\n".join(_joint_call(robot, j, limits) for j in joints)
-    return f"""  <xacro:macro name="{robot}_{group}_joints" params="use_fake_hardware use_sim">
+    # use_linkage only becomes a param when a joint in this group declares a
+    # four-bar, so groups/robots without one regenerate byte-identically.
+    extra = " use_linkage:=true" if any(j.get("linkage") for j in joints) else ""
+    return f"""  <xacro:macro name="{robot}_{group}_joints" params="use_fake_hardware use_sim{extra}">
 {calls}
   </xacro:macro>"""
 
@@ -179,16 +234,17 @@ def _combined_macro(
   </xacro:macro>"""
 
 
-def _real_block(robot: str, group: dict, real_plugin: str) -> str:
+def _real_block(robot: str, group: dict, real_plugin: str, use_linkage: bool = False) -> str:
     """One <ros2_control> bus block, indented as a direct child of the real macro."""
     can_arg = group["can_interface_arg"]
+    link_arg = ' use_linkage="${use_linkage}"' if use_linkage else ""
     return f"""    <ros2_control name="{group["block_name"]}" type="system">
       <hardware>
         <plugin>{real_plugin}</plugin>
         <param name="can_interface">${{{can_arg}}}</param>
         <param name="calibration_file">${{calibration_file}}</param>
       </hardware>
-      <xacro:{robot}_{group["name"]}_joints use_fake_hardware="false" use_sim="false"/>
+      <xacro:{robot}_{group["name"]}_joints use_fake_hardware="false" use_sim="false"{link_arg}/>
     </ros2_control>"""
 
 
@@ -216,11 +272,18 @@ def _real_imu_block(imu: dict) -> str:
     </ros2_control>"""
 
 
-def _real_macro(robot: str, groups: list[dict], backends: dict, imu: dict | None = None) -> str:
+def _real_macro(robot: str, groups: list[dict], backends: dict, imu: dict | None = None,
+                joints_by_group: dict[str, list[dict]] | None = None) -> str:
     real_plugin = backends["real"]
     blocks = []
+    # Group descriptors carry no joints, so linkage presence comes from the
+    # joints-by-group map the caller built.
+    jbg = joints_by_group or {}
+    any_linkage = any(j.get("linkage") for js in jbg.values() for j in js)
     for group in groups:
-        block = _real_block(robot, group, real_plugin)
+        block = _real_block(
+            robot, group, real_plugin,
+            use_linkage=any(j.get("linkage") for j in jbg.get(group["name"], [])))
         if group.get("stub"):
             # Stub buses only exist in mode=arms_neck; nest the block inside the guard.
             block = (
@@ -239,6 +302,8 @@ def _real_macro(robot: str, groups: list[dict], backends: dict, imu: dict | None
     params = "mode can_interface_left can_interface_right calibration_file"
     if real_imu:
         params += " imu_port"
+    if any_linkage:
+        params += " use_linkage"
     # Keep the header comment byte-identical for non-IMU robots (only the IMU
     # ones gain the "(plus the base IMU sensor)" note), so regenerating a robot
     # without a real IMU produces no diff.
@@ -258,15 +323,20 @@ def _real_macro(robot: str, groups: list[dict], backends: dict, imu: dict | None
   </xacro:macro>"""
 
 
-def _top_macro(robot: str, name: str, imu: dict | None = None) -> str:
+def _top_macro(robot: str, name: str, imu: dict | None = None,
+               any_linkage: bool = False) -> str:
     real_imu = bool(imu and imu.get("real_plugin"))
     imu_param = " imu_port" if real_imu else ""
     imu_pass = "\n        imu_port=\"${imu_port}\"" if real_imu else ""
+    # use_linkage is only threaded when some joint declares a four-bar, so
+    # robots without one regenerate byte-identically.
+    link_param = " use_linkage" if any_linkage else ""
+    link_pass = "\n        use_linkage=\"${use_linkage}\"" if any_linkage else ""
     return f"""  <!-- Top-level dispatch: combined block for sim/mock, per-bus blocks for real
        (use_sim wins over use_fake_hardware, matching franka_ros2 / UR precedence). -->
   <xacro:macro name="{robot}_ros2_control"
                params="name use_fake_hardware use_sim mode
-                       can_interface_left can_interface_right calibration_file{imu_param}">
+                       can_interface_left can_interface_right calibration_file{imu_param}{link_param}">
     <xacro:if value="${{use_sim or use_fake_hardware}}">
       <xacro:{robot}_ros2_control_combined name="${{name}}"
         use_fake_hardware="${{use_fake_hardware}}" use_sim="${{use_sim}}"/>
@@ -275,7 +345,7 @@ def _top_macro(robot: str, name: str, imu: dict | None = None) -> str:
       <xacro:{robot}_ros2_control_real mode="${{mode}}"
         can_interface_left="${{can_interface_left}}"
         can_interface_right="${{can_interface_right}}"
-        calibration_file="${{calibration_file}}"{imu_pass}/>
+        calibration_file="${{calibration_file}}"{imu_pass}{link_pass}/>
     </xacro:unless>
   </xacro:macro>"""
 
@@ -521,13 +591,16 @@ def build_ros2_control_xacro(robot: str, ros2_control: dict, limits: dict) -> st
 
     active_groups = [g for g in groups if not g.get("stub") and joints_by_group.get(g["name"])]
 
-    parts = [_joint_macro(robot, command, state)]
+    any_linkage = any(j.get("linkage") for j in ros2_control["joints"])
+    parts = [_joint_macro(robot, command, state, any_linkage)]
     for group in groups:
         parts.append(_group_macro(robot, group["name"], joints_by_group.get(group["name"], []), limits))
     imu = ros2_control.get("imu")
     parts.append(_combined_macro(robot, combined_name, active_groups, backends, imu))
-    parts.append(_real_macro(robot, groups, backends, imu))
-    parts.append(_top_macro(robot, combined_name, imu))
+    parts.append(_real_macro(robot, groups, backends, imu, joints_by_group))
+    parts.append(_top_macro(
+        robot, combined_name, imu,
+        any_linkage=any(j.get("linkage") for j in ros2_control["joints"])))
 
     body = "\n\n".join(parts)
     return (
@@ -562,6 +635,10 @@ def build_assembly_xacro(robot: str, ros2_control: dict | None, package: str = D
     name_attr = ros2_control.get("combined_block_name", f"{robot}_system")
     imu = ros2_control.get("imu")
     imu_pass = '\n    imu_port="$(arg imu_port)"' if (imu and imu.get("real_plugin")) else ""
+    # Only pass use_linkage when a joint declares a four-bar, so robots without
+    # one regenerate byte-identically.
+    link_pass = ('\n    use_linkage="$(arg use_linkage)"'
+                 if any(j.get("linkage") for j in ros2_control.get("joints", [])) else "")
     return f"""<?xml version="1.0"?>
 {_banner(robot)}
 <robot xmlns:xacro="http://www.ros.org/wiki/xacro" name="{robot}">
@@ -579,7 +656,7 @@ def build_assembly_xacro(robot: str, ros2_control: dict | None, package: str = D
     mode="$(arg mode)"
     can_interface_left="$(arg can_interface_left)"
     can_interface_right="$(arg can_interface_right)"
-    calibration_file="$(arg calibration_file)"{imu_pass}/>
+    calibration_file="$(arg calibration_file)"{imu_pass}{link_pass}/>
 </robot>
 """
 
diff --git a/robots/lite_bimanual/mjcf/lite_bimanual.xml b/robots/lite_bimanual/mjcf/lite_bimanual.xml
index 1fc4bbb..52a6ccd 100644
--- a/robots/lite_bimanual/mjcf/lite_bimanual.xml
+++ b/robots/lite_bimanual/mjcf/lite_bimanual.xml
@@ -114,4 +114,4 @@
       </body>
     </body>
   </worldbody>
-<actuator><motor name="left_shoulder_pitch" joint="left_shoulder_pitch" forcerange="-17 17" /><motor name="left_shoulder_roll" joint="left_shoulder_roll" forcerange="-14 14" /><motor name="left_shoulder_yaw" joint="left_shoulder_yaw" forcerange="-14 14" /><motor name="left_elbow_pitch" joint="left_elbow_pitch" forcerange="-14 14" /><motor name="left_wrist_yaw" joint="left_wrist_yaw" forcerange="-5.5 5.5" /><motor name="left_wrist_roll" joint="left_wrist_roll" forcerange="-5.5 5.5" /><motor name="left_wrist_pitch" joint="left_wrist_pitch" forcerange="-5.5 5.5" /><motor name="right_shoulder_pitch" joint="right_shoulder_pitch" forcerange="-17 17" /><motor name="right_shoulder_roll" joint="right_shoulder_roll" forcerange="-14 14" /><motor name="right_shoulder_yaw" joint="right_shoulder_yaw" forcerange="-14 14" /><motor name="right_elbow_pitch" joint="right_elbow_pitch" forcerange="-14 14" /><motor name="right_wrist_yaw" joint="right_wrist_yaw" forcerange="-5.5 5.5" /><motor name="right_wrist_roll" joint="right_wrist_roll" forcerange="-5.5 5.5" /><motor name="right_wrist_pitch" joint="right_wrist_pitch" forcerange="-5.5 5.5" /></actuator></mujoco>
\ No newline at end of file
+<actuator><position name="left_shoulder_pitch" joint="left_shoulder_pitch" forcerange="-17 17" /><position name="left_shoulder_roll" joint="left_shoulder_roll" forcerange="-14 14" /><position name="left_shoulder_yaw" joint="left_shoulder_yaw" forcerange="-14 14" /><position name="left_elbow_pitch" joint="left_elbow_pitch" forcerange="-14 14" /><position name="left_wrist_yaw" joint="left_wrist_yaw" forcerange="-5.5 5.5" /><position name="left_wrist_roll" joint="left_wrist_roll" forcerange="-5.5 5.5" /><position name="left_wrist_pitch" joint="left_wrist_pitch" forcerange="-5.5 5.5" /><position name="right_shoulder_pitch" joint="right_shoulder_pitch" forcerange="-17 17" /><position name="right_shoulder_roll" joint="right_shoulder_roll" forcerange="-14 14" /><position name="right_shoulder_yaw" joint="right_shoulder_yaw" forcerange="-14 14" /><position name="right_elbow_pitch" joint="right_elbow_pitch" forcerange="-14 14" /><position name="right_wrist_yaw" joint="right_wrist_yaw" forcerange="-5.5 5.5" /><position name="right_wrist_roll" joint="right_wrist_roll" forcerange="-5.5 5.5" /><position name="right_wrist_pitch" joint="right_wrist_pitch" forcerange="-5.5 5.5" /></actuator></mujoco>
\ No newline at end of file
diff --git a/robots/lite_biped/cad/ros2_control.json b/robots/lite_biped/cad/ros2_control.json
index 3884d35..1ca5f59 100644
--- a/robots/lite_biped/cad/ros2_control.json
+++ b/robots/lite_biped/cad/ros2_control.json
@@ -1,5 +1,5 @@
 {
-    "_comment": "ROS 2 hardware mapping for the lite_biped (legs-only floating-base humanoid). Drives generation of xacro/lite_biped.ros2_control.xacro. Joint position limits come from the URDF (single source). The sim/mock combined block also advertises a base IMU <sensor> (use_sim only), backed by the MJCF base_quat/base_gyro/base_accel sensors via MujocoSystem and republished by imu_sensor_broadcaster. real-hardware can_id set from a live bus scan (left can2 ids 31-37, right can3 ids 41-47); direction/current_limit still pending commissioning + leg calibration.",
+    "_comment": "ROS 2 hardware mapping for the lite_biped (legs-only floating-base humanoid). Drives generation of xacro/lite_biped.ros2_control.xacro. Joint position limits come from the URDF (single source). The sim/mock combined block also advertises a base IMU <sensor> (use_sim only), backed by the MJCF base_quat/base_gyro/base_accel sensors via MujocoSystem and republished by imu_sensor_broadcaster. real-hardware can_id set from a live bus scan (left can2 ids 31-37, right can3 ids 41-47); direction/current_limit still pending commissioning + leg calibration. ankle_pitch carries a FOUR-BAR linkage (actuator in the shin pushes a coupler to a crank on the foot): ground = sqrt(160^2+12^2) = 160.449369 mm (the actuator pivot is 160 above / 12 BEHIND the ankle pivot, so the ground link is NOT 160), cranks 40, coupler 150, alpha_zero 338.822130 deg, sign +1 -- verified against CAD (the coupler closes to 150.0000 mm at joint -30/0/+50). RobstrideSystem converts joint<->actuator through it and refers the commanded impedance by J^2. Pass use_linkage:=false for calibration, which needs raw actuator angles.",
 
     "interfaces": {
         "command": ["position", "velocity", "effort", "stiffness", "damping"],
@@ -19,7 +19,8 @@
         "can_interface_left": "can2",
         "can_interface_right": "can3",
         "calibration_file": "",
-        "imu_port": "/dev/ttyUSB0"
+        "imu_port": "/dev/ttyUSB0",
+        "use_linkage": "true"
     },
 
     "base_link": {"name": "base_link", "child": "pelvis"},
@@ -44,7 +45,7 @@
         {"name": "left_hip_yaw",     "group": "left_leg",  "can_id": 33, "model": "rs-02", "direction": 1, "torque_limit": 17.0, "current_limit": 27},
         {"name": "left_knee_pitch",  "group": "left_leg",  "can_id": 34, "model": "rs-06", "direction": -1, "torque_limit": 36.0, "current_limit": 43},
         {"name": "left_ankle_yaw",   "group": "left_leg",  "can_id": 35, "model": "rs-00", "direction": 1, "torque_limit": 14.0, "current_limit": 16},
-        {"name": "left_ankle_pitch", "group": "left_leg",  "can_id": 36, "model": "rs-00", "direction": 1, "torque_limit": 14.0, "current_limit": 16},
+        {"name": "left_ankle_pitch", "group": "left_leg",  "can_id": 36, "model": "rs-00", "direction": 1, "torque_limit": 14.0, "current_limit": 16, "linkage": {"ground": 160.449369, "crank_in": 40.0, "coupler": 150.0, "crank_out": 40.0, "alpha_zero": 338.822130, "sign": 1}},
         {"name": "left_ankle_roll",  "group": "left_leg",  "can_id": 37, "model": "rs-05", "direction": -1, "torque_limit": 5.5,  "current_limit": 14},
 
         {"name": "right_hip_pitch",   "group": "right_leg", "can_id": 41, "model": "rs-06", "direction": 1, "torque_limit": 36.0, "current_limit": 43},
@@ -52,7 +53,7 @@
         {"name": "right_hip_yaw",     "group": "right_leg", "can_id": 43, "model": "rs-02", "direction": 1, "torque_limit": 17.0, "current_limit": 27},
         {"name": "right_knee_pitch",  "group": "right_leg", "can_id": 44, "model": "rs-06", "direction": 1, "torque_limit": 36.0, "current_limit": 43},
         {"name": "right_ankle_yaw",   "group": "right_leg", "can_id": 45, "model": "rs-00", "direction": 1, "torque_limit": 14.0, "current_limit": 16},
-        {"name": "right_ankle_pitch", "group": "right_leg", "can_id": 46, "model": "rs-00", "direction": -1, "torque_limit": 14.0, "current_limit": 16},
+        {"name": "right_ankle_pitch", "group": "right_leg", "can_id": 46, "model": "rs-00", "direction": -1, "torque_limit": 14.0, "current_limit": 16, "linkage": {"ground": 160.449369, "crank_in": 40.0, "coupler": 150.0, "crank_out": 40.0, "alpha_zero": 338.822130, "sign": 1}},
         {"name": "right_ankle_roll",  "group": "right_leg", "can_id": 47, "model": "rs-05", "direction": -1, "torque_limit": 5.5,  "current_limit": 14}
     ]
 }
diff --git a/robots/lite_biped/cad/scad/left_foot.scad b/robots/lite_biped/cad/scad/left_foot.scad
index a3089dd..c4bffdc 100644
--- a/robots/lite_biped/cad/scad/left_foot.scad
+++ b/robots/lite_biped/cad/scad/left_foot.scad
@@ -1,8 +1,16 @@
 % scale(1000) import("left_foot.stl");
 
-translate([-70, -10, -760])
-cube([65, 120, 30], center=true);
+// flat sole -- these 8 carry the standing load (support 97.97 cm, 89.9%)
+translate([ -74.60, -79.98, -767.00]) sphere(r=8);
+translate([-109.41, -45.90, -767.00]) sphere(r=8);
+translate([ -41.96, -44.42, -767.00]) sphere(r=8);
+translate([-112.09,   7.64, -767.00]) sphere(r=8);
+translate([ -35.24,   8.77, -767.00]) sphere(r=8);
+translate([-114.32,  61.20, -767.00]) sphere(r=8);
+translate([ -28.52,  61.96, -767.00]) sphere(r=8);
+translate([ -70.47,  71.73, -767.00]) sphere(r=8);
 
-translate([-70, 85, -750])
-rotate([20, 0, 0])
-cube([70, 50, 30], center=true);
+// toe upturn -- clear the ground at neutral, engage as the foot pitches forward
+translate([-104.38, 104.89, -758.91]) sphere(r=8);
+translate([ -30.68, 105.97, -758.53]) sphere(r=8);
+translate([ -65.35, 128.74, -747.13]) sphere(r=8);
diff --git a/robots/lite_biped/cad/scad/right_foot.scad b/robots/lite_biped/cad/scad/right_foot.scad
index 7329a7f..d36b1bc 100644
--- a/robots/lite_biped/cad/scad/right_foot.scad
+++ b/robots/lite_biped/cad/scad/right_foot.scad
@@ -1,8 +1,16 @@
 % scale(1000) import("right_foot.stl");
 
-translate([70, -10, -760])
-cube([65, 120, 30], center=true);
+// flat sole -- these 8 carry the standing load (support 97.97 cm, 89.9%)
+translate([ 74.60, -79.98, -767.00]) sphere(r=8);
+translate([109.41, -45.90, -767.00]) sphere(r=8);
+translate([ 41.96, -44.42, -767.00]) sphere(r=8);
+translate([112.09,   7.64, -767.00]) sphere(r=8);
+translate([ 35.24,   8.77, -767.00]) sphere(r=8);
+translate([114.32,  61.20, -767.00]) sphere(r=8);
+translate([ 28.52,  61.96, -767.00]) sphere(r=8);
+translate([ 70.47,  71.73, -767.00]) sphere(r=8);
 
-translate([70, 85, -750])
-rotate([20, 0, 0])
-cube([70, 50, 30], center=true);
+// toe upturn -- clear the ground at neutral, engage as the foot pitches forward
+translate([104.38, 104.89, -758.91]) sphere(r=8);
+translate([ 30.68, 105.97, -758.53]) sphere(r=8);
+translate([ 65.35, 128.74, -747.13]) sphere(r=8);
diff --git a/robots/lite_biped/meshes/visual/left_foot_visual.stl b/robots/lite_biped/meshes/visual/left_foot_visual.stl
index c269e0c..2a4f650 100644
Binary files a/robots/lite_biped/meshes/visual/left_foot_visual.stl and b/robots/lite_biped/meshes/visual/left_foot_visual.stl differ
diff --git a/robots/lite_biped/meshes/visual/right_ankle_pitch_visual.stl b/robots/lite_biped/meshes/visual/right_ankle_pitch_visual.stl
index 7005a10..cdb84b0 100644
Binary files a/robots/lite_biped/meshes/visual/right_ankle_pitch_visual.stl and b/robots/lite_biped/meshes/visual/right_ankle_pitch_visual.stl differ
diff --git a/robots/lite_biped/meshes/visual/right_foot_visual.stl b/robots/lite_biped/meshes/visual/right_foot_visual.stl
index c999535..0fc6f19 100644
Binary files a/robots/lite_biped/meshes/visual/right_foot_visual.stl and b/robots/lite_biped/meshes/visual/right_foot_visual.stl differ
diff --git a/robots/lite_biped/mjcf/lite_biped.xml b/robots/lite_biped/mjcf/lite_biped.xml
index 4588c36..3900d3d 100644
--- a/robots/lite_biped/mjcf/lite_biped.xml
+++ b/robots/lite_biped/mjcf/lite_biped.xml
@@ -55,11 +55,20 @@
                   <joint name="left_ankle_pitch" pos="0 0 0" axis="0 0 1" range="-0.523599 0.872665" actuatorfrcrange="-14 14" frictionloss="0.1" armature="0.002" />
                   <geom pos="-0.00384209 0.0297371 3.1356e-08" quat="0.707105 0.707108 0 0" type="mesh" contype="0" conaffinity="0" group="1" density="0" rgba="0.933333 0.933333 0.933333 1" mesh="left_ankle_pitch_visual" />
                   <body name="left_foot" pos="0 0.04 0" quat="0.707105 0 0.707108 0">
-                    <inertial pos="0.00124938 0.0227876 0.0398042" quat="0.994259 -0.101477 0.0262886 0.021467" mass="0.44" diaginertia="0.00134078 0.00122657 0.000447531" />
+                    <inertial pos="-0.00237479 0.023215 0.0359752" quat="0.992439 -0.0818733 0.0284825 0.0868931" mass="0.44" diaginertia="0.00152195 0.00141506 0.000450226" />
                     <joint name="left_ankle_roll" pos="0 0 0" axis="0 0 1" range="-0.349066 0.349066" actuatorfrcrange="-5.5 5.5" frictionloss="0.1" armature="0.001" />
-                    <geom size="0.0325 0.06 0.015" pos="0 0.05 0.015" quat="0.707105 0.707108 0 0" type="box" condim="3" friction="0.6 0.005 0.0001" priority="1" />
-                    <geom size="0.035 0.025 0.015" pos="0 0.04 0.11" quat="0.573577 0.819151 0 0" type="box" condim="3" friction="0.6 0.005 0.0001" priority="1" />
-                    <geom pos="0.00124938 0.0227876 0.0398042" quat="0.499998 0.5 -0.5 0.500002" type="mesh" contype="0" conaffinity="0" group="1" density="0" rgba="0.933333 0.933333 0.933333 1" mesh="left_foot_visual" />
+                    <geom size="0.008" pos="-0.0046 0.057 -0.05998" quat="0.707105 0.707108 0 0" condim="3" friction="0.6 0.005 0.0001" priority="1" />
+                    <geom size="0.008" pos="-0.03941 0.057 -0.0259" quat="0.707105 0.707108 0 0" condim="3" friction="0.6 0.005 0.0001" priority="1" />
+                    <geom size="0.008" pos="0.02804 0.057 -0.02442" quat="0.707105 0.707108 0 0" condim="3" friction="0.6 0.005 0.0001" priority="1" />
+                    <geom size="0.008" pos="-0.04209 0.057 0.02764" quat="0.707105 0.707108 0 0" condim="3" friction="0.6 0.005 0.0001" priority="1" />
+                    <geom size="0.008" pos="0.03476 0.057 0.02877" quat="0.707105 0.707108 0 0" condim="3" friction="0.6 0.005 0.0001" priority="1" />
+                    <geom size="0.008" pos="-0.04432 0.057 0.0812" quat="0.707105 0.707108 0 0" condim="3" friction="0.6 0.005 0.0001" priority="1" />
+                    <geom size="0.008" pos="0.04148 0.057 0.08196" quat="0.707105 0.707108 0 0" condim="3" friction="0.6 0.005 0.0001" priority="1" />
+                    <geom size="0.008" pos="-0.00047 0.057 0.09173" quat="0.707105 0.707108 0 0" condim="3" friction="0.6 0.005 0.0001" priority="1" />
+                    <geom size="0.008" pos="-0.03438 0.04891 0.12489" quat="0.707105 0.707108 0 0" condim="3" friction="0.6 0.005 0.0001" priority="1" />
+                    <geom size="0.008" pos="0.03932 0.04853 0.12597" quat="0.707105 0.707108 0 0" condim="3" friction="0.6 0.005 0.0001" priority="1" />
+                    <geom size="0.008" pos="0.00465 0.03713 0.14874" quat="0.707105 0.707108 0 0" condim="3" friction="0.6 0.005 0.0001" priority="1" />
+                    <geom pos="-0.00237479 0.023215 0.0359752" quat="0.499998 0.5 -0.5 0.500002" type="mesh" contype="0" conaffinity="0" group="1" density="0" rgba="0.933333 0.933333 0.933333 1" mesh="left_foot_visual" />
                   </body>
                 </body>
               </body>
@@ -72,10 +81,10 @@
         <joint name="right_hip_pitch" pos="0 0 0" axis="0 0 1" range="-2.35619 0.785398" actuatorfrcrange="-36 36" frictionloss="0.1" armature="0.008" />
         <geom pos="-0.0114771 0.00418737 -0.0187964" quat="0.766046 0.642786 0 0" type="mesh" contype="0" conaffinity="0" group="1" density="0" rgba="0.933333 0.933333 0.933333 1" mesh="right_hip_pitch_visual" />
         <body name="right_hip_roll" quat="0.704416 0.0616286 0.683012 -0.183015">
-          <inertial pos="-1.13349e-07 0.0525083 -0.0652488" quat="0.382434 0.594774 -0.594759 0.382426" mass="0.93" diaginertia="0.00285206 0.00263147 0.00112674" />
+          <inertial pos="2.6715e-08 0.0525085 -0.0652483" quat="0.382434 0.594774 -0.594759 0.382426" mass="0.93" diaginertia="0.00285206 0.00263147 0.00112674" />
           <joint name="right_hip_roll" pos="0 0 0" axis="0 0 1" range="-1.5708 0.349066" actuatorfrcrange="-36 36" frictionloss="0.1" armature="0.008" />
-          <geom size="0.05 0.075" pos="0 0.181098 -0.0871979" quat="0.819152 0.573576 0 0" type="capsule" condim="1" />
-          <geom pos="-1.13349e-07 0.0525083 -0.0652488" quat="0.579227 0.40558 -0.405579 0.579229" type="mesh" contype="0" conaffinity="0" group="1" density="0" rgba="0.933333 0.933333 0.933333 1" mesh="right_hip_roll_visual" />
+          <geom size="0.05 0.075" pos="1.40064e-07 0.181098 -0.0871974" quat="0.819152 0.573576 0 0" type="capsule" condim="1" />
+          <geom pos="2.6715e-08 0.0525085 -0.0652483" quat="0.579227 0.40558 -0.405579 0.579229" type="mesh" contype="0" conaffinity="0" group="1" density="0" rgba="0.933333 0.933333 0.933333 1" mesh="right_hip_roll_visual" />
           <body name="right_hip_yaw" pos="0 -0.0068404 -0.0187939" quat="0.579227 0.40558 -0.405579 0.579229">
             <inertial pos="0.00130421 2.35733e-05 -0.237299" quat="0.705202 0.0179505 0.0178929 0.708554" mass="1.54" diaginertia="0.00874705 0.00858133 0.00191154" />
             <joint name="right_hip_yaw" pos="0 0 0" axis="0 0 1" range="-1.5708 1.5708" actuatorfrcrange="-17 17" frictionloss="0.1" armature="0.005" />
@@ -94,11 +103,20 @@
                   <joint name="right_ankle_pitch" pos="0 0 0" axis="0 0 1" range="-0.523599 0.872665" actuatorfrcrange="-14 14" frictionloss="0.1" armature="0.002" />
                   <geom pos="-0.00384209 0.0297371 3.1396e-08" quat="0.707105 0.707108 0 0" type="mesh" contype="0" conaffinity="0" group="1" density="0" rgba="0.933333 0.933333 0.933333 1" mesh="right_ankle_pitch_visual" />
                   <body name="right_foot" pos="0 0.04 0" quat="0.707105 0 0.707108 0">
-                    <inertial pos="-0.0012494 0.0227876 0.039804" quat="0.994259 -0.101477 -0.0262888 -0.0214685" mass="0.44" diaginertia="0.00134078 0.00122657 0.000447531" />
+                    <inertial pos="0.0023746 0.0232151 0.0359757" quat="0.992441 -0.0818772 -0.028477 -0.0868657" mass="0.44" diaginertia="0.00152196 0.00141506 0.000450227" />
                     <joint name="right_ankle_roll" pos="0 0 0" axis="0 0 1" range="-0.349066 0.349066" actuatorfrcrange="-5.5 5.5" frictionloss="0.1" armature="0.001" />
-                    <geom size="0.0325 0.06 0.015" pos="0 0.05 0.015" quat="0.707105 0.707108 0 0" type="box" condim="3" friction="0.6 0.005 0.0001" priority="1" />
-                    <geom size="0.035 0.025 0.015" pos="0 0.04 0.11" quat="0.573577 0.819151 0 0" type="box" condim="3" friction="0.6 0.005 0.0001" priority="1" />
-                    <geom pos="-0.0012494 0.0227876 0.039804" quat="0.499998 0.5 -0.5 0.500002" type="mesh" contype="0" conaffinity="0" group="1" density="0" rgba="0.933333 0.933333 0.933333 1" mesh="right_foot_visual" />
+                    <geom size="0.008" pos="0.0046 0.057 -0.05998" quat="0.707105 0.707108 0 0" condim="3" friction="0.6 0.005 0.0001" priority="1" />
+                    <geom size="0.008" pos="0.03941 0.057 -0.0259" quat="0.707105 0.707108 0 0" condim="3" friction="0.6 0.005 0.0001" priority="1" />
+                    <geom size="0.008" pos="-0.02804 0.057 -0.02442" quat="0.707105 0.707108 0 0" condim="3" friction="0.6 0.005 0.0001" priority="1" />
+                    <geom size="0.008" pos="0.04209 0.057 0.02764" quat="0.707105 0.707108 0 0" condim="3" friction="0.6 0.005 0.0001" priority="1" />
+                    <geom size="0.008" pos="-0.03476 0.057 0.02877" quat="0.707105 0.707108 0 0" condim="3" friction="0.6 0.005 0.0001" priority="1" />
+                    <geom size="0.008" pos="0.04432 0.057 0.0812" quat="0.707105 0.707108 0 0" condim="3" friction="0.6 0.005 0.0001" priority="1" />
+                    <geom size="0.008" pos="-0.04148 0.057 0.08196" quat="0.707105 0.707108 0 0" condim="3" friction="0.6 0.005 0.0001" priority="1" />
+                    <geom size="0.008" pos="0.00047 0.057 0.09173" quat="0.707105 0.707108 0 0" condim="3" friction="0.6 0.005 0.0001" priority="1" />
+                    <geom size="0.008" pos="0.03438 0.04891 0.12489" quat="0.707105 0.707108 0 0" condim="3" friction="0.6 0.005 0.0001" priority="1" />
+                    <geom size="0.008" pos="-0.03932 0.04853 0.12597" quat="0.707105 0.707108 0 0" condim="3" friction="0.6 0.005 0.0001" priority="1" />
+                    <geom size="0.008" pos="-0.00465 0.03713 0.14874" quat="0.707105 0.707108 0 0" condim="3" friction="0.6 0.005 0.0001" priority="1" />
+                    <geom pos="0.0023746 0.0232151 0.0359757" quat="0.499998 0.5 -0.5 0.500002" type="mesh" contype="0" conaffinity="0" group="1" density="0" rgba="0.933333 0.933333 0.933333 1" mesh="right_foot_visual" />
                   </body>
                 </body>
               </body>
@@ -108,4 +126,4 @@
       </body>
     </body>
   </worldbody>
-<sensor><framequat name="base_quat" objtype="site" objname="imu_site" /><gyro name="base_gyro" site="imu_site" /><accelerometer name="base_accel" site="imu_site" /><velocimeter name="base_vel" site="imu_site" /><framepos name="base_pos" objtype="site" objname="imu_site" /></sensor><actuator><motor name="left_hip_pitch" joint="left_hip_pitch" forcerange="-36.0 36.0" /><motor name="left_hip_roll" joint="left_hip_roll" forcerange="-36.0 36.0" /><motor name="left_hip_yaw" joint="left_hip_yaw" forcerange="-17.0 17.0" /><motor name="left_knee_pitch" joint="left_knee_pitch" forcerange="-36.0 36.0" /><motor name="left_ankle_yaw" joint="left_ankle_yaw" forcerange="-14.0 14.0" /><motor name="left_ankle_pitch" joint="left_ankle_pitch" forcerange="-14.0 14.0" /><motor name="left_ankle_roll" joint="left_ankle_roll" forcerange="-5.5 5.5" /><motor name="right_hip_pitch" joint="right_hip_pitch" forcerange="-36.0 36.0" /><motor name="right_hip_roll" joint="right_hip_roll" forcerange="-36.0 36.0" /><motor name="right_hip_yaw" joint="right_hip_yaw" forcerange="-17.0 17.0" /><motor name="right_knee_pitch" joint="right_knee_pitch" forcerange="-36.0 36.0" /><motor name="right_ankle_yaw" joint="right_ankle_yaw" forcerange="-14.0 14.0" /><motor name="right_ankle_pitch" joint="right_ankle_pitch" forcerange="-14.0 14.0" /><motor name="right_ankle_roll" joint="right_ankle_roll" forcerange="-5.5 5.5" /></actuator></mujoco>
\ No newline at end of file
+<sensor><framequat name="base_quat" objtype="site" objname="imu_site" /><gyro name="base_gyro" site="imu_site" /><accelerometer name="base_accel" site="imu_site" /><velocimeter name="base_vel" site="imu_site" /><framepos name="base_pos" objtype="site" objname="imu_site" /></sensor><actuator><position name="left_hip_pitch" joint="left_hip_pitch" forcerange="-36.0 36.0" /><position name="left_hip_roll" joint="left_hip_roll" forcerange="-36.0 36.0" /><position name="left_hip_yaw" joint="left_hip_yaw" forcerange="-17.0 17.0" /><position name="left_knee_pitch" joint="left_knee_pitch" forcerange="-36.0 36.0" /><position name="left_ankle_yaw" joint="left_ankle_yaw" forcerange="-14.0 14.0" /><position name="left_ankle_pitch" joint="left_ankle_pitch" forcerange="-14.0 14.0" /><position name="left_ankle_roll" joint="left_ankle_roll" forcerange="-5.5 5.5" /><position name="right_hip_pitch" joint="right_hip_pitch" forcerange="-36.0 36.0" /><position name="right_hip_roll" joint="right_hip_roll" forcerange="-36.0 36.0" /><position name="right_hip_yaw" joint="right_hip_yaw" forcerange="-17.0 17.0" /><position name="right_knee_pitch" joint="right_knee_pitch" forcerange="-36.0 36.0" /><position name="right_ankle_yaw" joint="right_ankle_yaw" forcerange="-14.0 14.0" /><position name="right_ankle_pitch" joint="right_ankle_pitch" forcerange="-14.0 14.0" /><position name="right_ankle_roll" joint="right_ankle_roll" forcerange="-5.5 5.5" /></actuator></mujoco>
\ No newline at end of file
diff --git a/robots/lite_biped/urdf/lite_biped.urdf b/robots/lite_biped/urdf/lite_biped.urdf
index b2c743a..9665de2 100644
--- a/robots/lite_biped/urdf/lite_biped.urdf
+++ b/robots/lite_biped/urdf/lite_biped.urdf
@@ -156,25 +156,79 @@
   <!-- Link left_foot -->
   <link name="left_foot">
     <inertial>
-      <origin xyz="0.00124938 0.0227876 0.0398042" rpy="0 0 0" />
+      <origin xyz="-0.00237479 0.023215 0.0359752" rpy="0 0 0" />
       <mass value="0.44" />
-      <inertia ixx="0.00133847" ixy="-3.31857e-06" ixz="-4.29633e-05" iyy="0.00119465" iyz="-0.000154848" izz="0.000481763" />
+      <inertia ixx="0.00151668" ixy="1.08029e-05" ixz="-4.76424e-05" iyy="0.00139101" iyz="-0.00016041" izz="0.000479544" />
     </inertial>
     <!-- Part left_foot_parts -->
     <collision>
-      <origin xyz="0 0.05 0.015" rpy="1.5708 0 0" />
+      <origin xyz="-0.0046 0.057 -0.05998" rpy="1.5708 0 0" />
       <geometry>
-        <box size="0.065 0.12 0.03" />
+        <sphere radius="0.008" />
       </geometry>
     </collision>
     <collision>
-      <origin xyz="0 0.04 0.11" rpy="1.91986 0 0" />
+      <origin xyz="-0.03941 0.057 -0.0259" rpy="1.5708 0 0" />
       <geometry>
-        <box size="0.07 0.05 0.03" />
+        <sphere radius="0.008" />
+      </geometry>
+    </collision>
+    <collision>
+      <origin xyz="0.02804 0.057 -0.02442" rpy="1.5708 0 0" />
+      <geometry>
+        <sphere radius="0.008" />
+      </geometry>
+    </collision>
+    <collision>
+      <origin xyz="-0.04209 0.057 0.02764" rpy="1.5708 0 0" />
+      <geometry>
+        <sphere radius="0.008" />
+      </geometry>
+    </collision>
+    <collision>
+      <origin xyz="0.03476 0.057 0.02877" rpy="1.5708 0 0" />
+      <geometry>
+        <sphere radius="0.008" />
+      </geometry>
+    </collision>
+    <collision>
+      <origin xyz="-0.04432 0.057 0.0812" rpy="1.5708 0 0" />
+      <geometry>
+        <sphere radius="0.008" />
+      </geometry>
+    </collision>
+    <collision>
+      <origin xyz="0.04148 0.057 0.08196" rpy="1.5708 0 0" />
+      <geometry>
+        <sphere radius="0.008" />
+      </geometry>
+    </collision>
+    <collision>
+      <origin xyz="-0.00047 0.057 0.09173" rpy="1.5708 0 0" />
+      <geometry>
+        <sphere radius="0.008" />
+      </geometry>
+    </collision>
+    <collision>
+      <origin xyz="-0.03438 0.04891 0.12489" rpy="1.5708 0 0" />
+      <geometry>
+        <sphere radius="0.008" />
+      </geometry>
+    </collision>
+    <collision>
+      <origin xyz="0.03932 0.04853 0.12597" rpy="1.5708 0 0" />
+      <geometry>
+        <sphere radius="0.008" />
+      </geometry>
+    </collision>
+    <collision>
+      <origin xyz="0.00465 0.03713 0.14874" rpy="1.5708 0 0" />
+      <geometry>
+        <sphere radius="0.008" />
       </geometry>
     </collision>
     <visual>
-      <origin xyz="0.00124938 0.0227876 0.0398042" rpy="1.5708 -1.5708 0" />
+      <origin xyz="-0.00237479 0.023215 0.0359752" rpy="1.5708 -1.5708 0" />
       <geometry>
         <mesh filename="../meshes/visual/left_foot_visual.stl" />
       </geometry>
@@ -185,7 +239,7 @@
   </link>
   <!-- Joint from left_ankle_pitch to left_foot -->
   <joint name="left_ankle_roll" type="revolute">
-    <origin xyz="-0 0.04 0" rpy="0 1.5708 0" />
+    <origin xyz="0 0.04 -0" rpy="0 1.5708 0" />
     <parent link="left_ankle_pitch" />
     <child link="left_foot" />
     <axis xyz="0 0 1" />
@@ -267,19 +321,19 @@
   <!-- Link right_hip_roll -->
   <link name="right_hip_roll">
     <inertial>
-      <origin xyz="-1.13349e-07 0.0525083 -0.0652488" rpy="0 0 0" />
+      <origin xyz="2.6715e-08 0.0525085 -0.0652483" rpy="0 0 0" />
       <mass value="0.93" />
       <inertia ixx="0.00263147" ixy="2.71e-10" ixz="6.079e-09" iyy="0.00142387" iyz="-0.000651423" izz="0.00255493" />
     </inertial>
     <!-- Part right_hip_roll_parts -->
     <collision>
-      <origin xyz="-0 0.181098 -0.0871979" rpy="1.22173 0 0" />
+      <origin xyz="1.40064e-07 0.181098 -0.0871974" rpy="1.22173 0 -0" />
       <geometry>
         <cylinder length="0.15" radius="0.05" />
       </geometry>
     </collision>
     <visual>
-      <origin xyz="-1.13349e-07 0.0525083 -0.0652488" rpy="0 -1.22173 1.5708" />
+      <origin xyz="2.6715e-08 0.0525085 -0.0652483" rpy="0 -1.22173 1.5708" />
       <geometry>
         <mesh filename="../meshes/visual/right_hip_roll_visual.stl" />
       </geometry>
@@ -297,7 +351,7 @@
     </inertial>
     <!-- Part right_hip_yaw_parts -->
     <visual>
-      <origin xyz="0.00130421 2.35733e-05 -0.237299" rpy="0 0 0" />
+      <origin xyz="0.00130421 2.35733e-05 -0.237299" rpy="0 0 -0" />
       <geometry>
         <mesh filename="../meshes/visual/right_hip_yaw_visual.stl" />
       </geometry>
@@ -321,7 +375,7 @@
       </geometry>
     </collision>
     <visual>
-      <origin xyz="-0.0048642 0.0372186 0.000224747" rpy="1.5708 -0 0" />
+      <origin xyz="-0.0048642 0.0372186 0.000224747" rpy="1.5708 0 0" />
       <geometry>
         <mesh filename="../meshes/visual/right_knee_pitch_visual.stl" />
       </geometry>
@@ -339,7 +393,7 @@
     </inertial>
     <!-- Part right_ankle_yaw_parts -->
     <visual>
-      <origin xyz="-0.00304908 -0.0015054 -0.185348" rpy="0 0 0" />
+      <origin xyz="-0.00304908 -0.0015054 -0.185348" rpy="0 0 -0" />
       <geometry>
         <mesh filename="../meshes/visual/right_ankle_yaw_visual.stl" />
       </geometry>
@@ -357,7 +411,7 @@
     </inertial>
     <!-- Part right_ankle_pitch_parts -->
     <visual>
-      <origin xyz="-0.00384209 0.0297371 3.1396e-08" rpy="1.5708 -0 0" />
+      <origin xyz="-0.00384209 0.0297371 3.1396e-08" rpy="1.5708 0 0" />
       <geometry>
         <mesh filename="../meshes/visual/right_ankle_pitch_visual.stl" />
       </geometry>
@@ -369,25 +423,79 @@
   <!-- Link right_foot -->
   <link name="right_foot">
     <inertial>
-      <origin xyz="-0.0012494 0.0227876 0.039804" rpy="0 0 0" />
+      <origin xyz="0.0023746 0.0232151 0.0359757" rpy="0 0 0" />
       <mass value="0.44" />
-      <inertia ixx="0.00133847" ixy="3.3182e-06" ixz="4.29635e-05" iyy="0.00119465" iyz="-0.000154847" izz="0.000481763" />
+      <inertia ixx="0.00151669" ixy="-1.0799e-05" ixz="4.76345e-05" iyy="0.00139101" iyz="-0.000160415" izz="0.000479546" />
     </inertial>
     <!-- Part right_foot_parts -->
     <collision>
-      <origin xyz="0 0.05 0.015" rpy="1.5708 0 -0" />
+      <origin xyz="0.0046 0.057 -0.05998" rpy="1.5708 0 0" />
+      <geometry>
+        <sphere radius="0.008" />
+      </geometry>
+    </collision>
+    <collision>
+      <origin xyz="0.03941 0.057 -0.0259" rpy="1.5708 0 0" />
+      <geometry>
+        <sphere radius="0.008" />
+      </geometry>
+    </collision>
+    <collision>
+      <origin xyz="-0.02804 0.057 -0.02442" rpy="1.5708 0 0" />
+      <geometry>
+        <sphere radius="0.008" />
+      </geometry>
+    </collision>
+    <collision>
+      <origin xyz="0.04209 0.057 0.02764" rpy="1.5708 0 0" />
+      <geometry>
+        <sphere radius="0.008" />
+      </geometry>
+    </collision>
+    <collision>
+      <origin xyz="-0.03476 0.057 0.02877" rpy="1.5708 0 0" />
+      <geometry>
+        <sphere radius="0.008" />
+      </geometry>
+    </collision>
+    <collision>
+      <origin xyz="0.04432 0.057 0.0812" rpy="1.5708 0 0" />
+      <geometry>
+        <sphere radius="0.008" />
+      </geometry>
+    </collision>
+    <collision>
+      <origin xyz="-0.04148 0.057 0.08196" rpy="1.5708 0 0" />
+      <geometry>
+        <sphere radius="0.008" />
+      </geometry>
+    </collision>
+    <collision>
+      <origin xyz="0.00047 0.057 0.09173" rpy="1.5708 0 0" />
+      <geometry>
+        <sphere radius="0.008" />
+      </geometry>
+    </collision>
+    <collision>
+      <origin xyz="0.03438 0.04891 0.12489" rpy="1.5708 0 0" />
+      <geometry>
+        <sphere radius="0.008" />
+      </geometry>
+    </collision>
+    <collision>
+      <origin xyz="-0.03932 0.04853 0.12597" rpy="1.5708 0 0" />
       <geometry>
-        <box size="0.065 0.12 0.03" />
+        <sphere radius="0.008" />
       </geometry>
     </collision>
     <collision>
-      <origin xyz="0 0.04 0.11" rpy="1.91986 0 -0" />
+      <origin xyz="-0.00465 0.03713 0.14874" rpy="1.5708 0 0" />
       <geometry>
-        <box size="0.07 0.05 0.03" />
+        <sphere radius="0.008" />
       </geometry>
     </collision>
     <visual>
-      <origin xyz="-0.0012494 0.0227876 0.039804" rpy="1.5708 -1.5708 0" />
+      <origin xyz="0.0023746 0.0232151 0.0359757" rpy="1.5708 -1.5708 0" />
       <geometry>
         <mesh filename="../meshes/visual/right_foot_visual.stl" />
       </geometry>
@@ -398,7 +506,7 @@
   </link>
   <!-- Joint from right_ankle_pitch to right_foot -->
   <joint name="right_ankle_roll" type="revolute">
-    <origin xyz="-0 0.04 -0" rpy="-0 1.5708 0" />
+    <origin xyz="0 0.04 0" rpy="0 1.5708 0" />
     <parent link="right_ankle_pitch" />
     <child link="right_foot" />
     <axis xyz="0 0 1" />
@@ -407,7 +515,7 @@
   </joint>
   <!-- Joint from right_ankle_yaw to right_ankle_pitch -->
   <joint name="right_ankle_pitch" type="revolute">
-    <origin xyz="0.01 0 -0.34" rpy="-1.5708 0 0" />
+    <origin xyz="0.01 0 -0.34" rpy="-1.5708 -0 -0" />
     <parent link="right_ankle_yaw" />
     <child link="right_ankle_pitch" />
     <axis xyz="0 0 1" />
@@ -416,7 +524,7 @@
   </joint>
   <!-- Joint from right_knee_pitch to right_ankle_yaw -->
   <joint name="right_ankle_yaw" type="revolute">
-    <origin xyz="-0.015 0 -0" rpy="1.5708 -0 -0" />
+    <origin xyz="-0.015 0 0" rpy="1.5708 -0 -0" />
     <parent link="right_knee_pitch" />
     <child link="right_ankle_yaw" />
     <axis xyz="0 0 1" />
@@ -434,7 +542,7 @@
   </joint>
   <!-- Joint from right_hip_roll to right_hip_yaw -->
   <joint name="right_hip_yaw" type="revolute">
-    <origin xyz="-0 -0.0068404 -0.0187939" rpy="0 -1.22173 1.5708" />
+    <origin xyz="-0 -0.0068404 -0.0187939" rpy="-0 -1.22173 1.5708" />
     <parent link="right_hip_roll" />
     <child link="right_hip_yaw" />
     <axis xyz="0 0 1" />
diff --git a/robots/lite_biped/xacro/lite_biped.description.xacro b/robots/lite_biped/xacro/lite_biped.description.xacro
index df80156..f18ee63 100644
--- a/robots/lite_biped/xacro/lite_biped.description.xacro
+++ b/robots/lite_biped/xacro/lite_biped.description.xacro
@@ -164,25 +164,79 @@
     <!-- Link left_foot -->
     <link name="left_foot">
       <inertial>
-        <origin xyz="0.00124938 0.0227876 0.0398042" rpy="0 0 0" />
+        <origin xyz="-0.00237479 0.023215 0.0359752" rpy="0 0 0" />
         <mass value="0.44" />
-        <inertia ixx="0.00133847" ixy="-3.31857e-06" ixz="-4.29633e-05" iyy="0.00119465" iyz="-0.000154848" izz="0.000481763" />
+        <inertia ixx="0.00151668" ixy="1.08029e-05" ixz="-4.76424e-05" iyy="0.00139101" iyz="-0.00016041" izz="0.000479544" />
       </inertial>
       <!-- Part left_foot_parts -->
       <collision>
-        <origin xyz="0 0.05 0.015" rpy="1.5708 0 0" />
+        <origin xyz="-0.0046 0.057 -0.05998" rpy="1.5708 0 0" />
         <geometry>
-          <box size="0.065 0.12 0.03" />
+          <sphere radius="0.008" />
         </geometry>
       </collision>
       <collision>
-        <origin xyz="0 0.04 0.11" rpy="1.91986 0 0" />
+        <origin xyz="-0.03941 0.057 -0.0259" rpy="1.5708 0 0" />
         <geometry>
-          <box size="0.07 0.05 0.03" />
+          <sphere radius="0.008" />
+        </geometry>
+      </collision>
+      <collision>
+        <origin xyz="0.02804 0.057 -0.02442" rpy="1.5708 0 0" />
+        <geometry>
+          <sphere radius="0.008" />
+        </geometry>
+      </collision>
+      <collision>
+        <origin xyz="-0.04209 0.057 0.02764" rpy="1.5708 0 0" />
+        <geometry>
+          <sphere radius="0.008" />
+        </geometry>
+      </collision>
+      <collision>
+        <origin xyz="0.03476 0.057 0.02877" rpy="1.5708 0 0" />
+        <geometry>
+          <sphere radius="0.008" />
+        </geometry>
+      </collision>
+      <collision>
+        <origin xyz="-0.04432 0.057 0.0812" rpy="1.5708 0 0" />
+        <geometry>
+          <sphere radius="0.008" />
+        </geometry>
+      </collision>
+      <collision>
+        <origin xyz="0.04148 0.057 0.08196" rpy="1.5708 0 0" />
+        <geometry>
+          <sphere radius="0.008" />
+        </geometry>
+      </collision>
+      <collision>
+        <origin xyz="-0.00047 0.057 0.09173" rpy="1.5708 0 0" />
+        <geometry>
+          <sphere radius="0.008" />
+        </geometry>
+      </collision>
+      <collision>
+        <origin xyz="-0.03438 0.04891 0.12489" rpy="1.5708 0 0" />
+        <geometry>
+          <sphere radius="0.008" />
+        </geometry>
+      </collision>
+      <collision>
+        <origin xyz="0.03932 0.04853 0.12597" rpy="1.5708 0 0" />
+        <geometry>
+          <sphere radius="0.008" />
+        </geometry>
+      </collision>
+      <collision>
+        <origin xyz="0.00465 0.03713 0.14874" rpy="1.5708 0 0" />
+        <geometry>
+          <sphere radius="0.008" />
         </geometry>
       </collision>
       <visual>
-        <origin xyz="0.00124938 0.0227876 0.0398042" rpy="1.5708 -1.5708 0" />
+        <origin xyz="-0.00237479 0.023215 0.0359752" rpy="1.5708 -1.5708 0" />
         <geometry>
           <mesh filename="${mesh_root}/left_foot_visual.stl" />
         </geometry>
@@ -193,7 +247,7 @@
     </link>
     <!-- Joint from left_ankle_pitch to left_foot -->
     <joint name="left_ankle_roll" type="revolute">
-      <origin xyz="-0 0.04 0" rpy="0 1.5708 0" />
+      <origin xyz="0 0.04 -0" rpy="0 1.5708 0" />
       <parent link="left_ankle_pitch" />
       <child link="left_foot" />
       <axis xyz="0 0 1" />
@@ -275,19 +329,19 @@
     <!-- Link right_hip_roll -->
     <link name="right_hip_roll">
       <inertial>
-        <origin xyz="-1.13349e-07 0.0525083 -0.0652488" rpy="0 0 0" />
+        <origin xyz="2.6715e-08 0.0525085 -0.0652483" rpy="0 0 0" />
         <mass value="0.93" />
         <inertia ixx="0.00263147" ixy="2.71e-10" ixz="6.079e-09" iyy="0.00142387" iyz="-0.000651423" izz="0.00255493" />
       </inertial>
       <!-- Part right_hip_roll_parts -->
       <collision>
-        <origin xyz="-0 0.181098 -0.0871979" rpy="1.22173 0 0" />
+        <origin xyz="1.40064e-07 0.181098 -0.0871974" rpy="1.22173 0 -0" />
         <geometry>
           <cylinder length="0.15" radius="0.05" />
         </geometry>
       </collision>
       <visual>
-        <origin xyz="-1.13349e-07 0.0525083 -0.0652488" rpy="0 -1.22173 1.5708" />
+        <origin xyz="2.6715e-08 0.0525085 -0.0652483" rpy="0 -1.22173 1.5708" />
         <geometry>
           <mesh filename="${mesh_root}/right_hip_roll_visual.stl" />
         </geometry>
@@ -305,7 +359,7 @@
       </inertial>
       <!-- Part right_hip_yaw_parts -->
       <visual>
-        <origin xyz="0.00130421 2.35733e-05 -0.237299" rpy="0 0 0" />
+        <origin xyz="0.00130421 2.35733e-05 -0.237299" rpy="0 0 -0" />
         <geometry>
           <mesh filename="${mesh_root}/right_hip_yaw_visual.stl" />
         </geometry>
@@ -329,7 +383,7 @@
         </geometry>
       </collision>
       <visual>
-        <origin xyz="-0.0048642 0.0372186 0.000224747" rpy="1.5708 -0 0" />
+        <origin xyz="-0.0048642 0.0372186 0.000224747" rpy="1.5708 0 0" />
         <geometry>
           <mesh filename="${mesh_root}/right_knee_pitch_visual.stl" />
         </geometry>
@@ -347,7 +401,7 @@
       </inertial>
       <!-- Part right_ankle_yaw_parts -->
       <visual>
-        <origin xyz="-0.00304908 -0.0015054 -0.185348" rpy="0 0 0" />
+        <origin xyz="-0.00304908 -0.0015054 -0.185348" rpy="0 0 -0" />
         <geometry>
           <mesh filename="${mesh_root}/right_ankle_yaw_visual.stl" />
         </geometry>
@@ -365,7 +419,7 @@
       </inertial>
       <!-- Part right_ankle_pitch_parts -->
       <visual>
-        <origin xyz="-0.00384209 0.0297371 3.1396e-08" rpy="1.5708 -0 0" />
+        <origin xyz="-0.00384209 0.0297371 3.1396e-08" rpy="1.5708 0 0" />
         <geometry>
           <mesh filename="${mesh_root}/right_ankle_pitch_visual.stl" />
         </geometry>
@@ -377,25 +431,79 @@
     <!-- Link right_foot -->
     <link name="right_foot">
       <inertial>
-        <origin xyz="-0.0012494 0.0227876 0.039804" rpy="0 0 0" />
+        <origin xyz="0.0023746 0.0232151 0.0359757" rpy="0 0 0" />
         <mass value="0.44" />
-        <inertia ixx="0.00133847" ixy="3.3182e-06" ixz="4.29635e-05" iyy="0.00119465" iyz="-0.000154847" izz="0.000481763" />
+        <inertia ixx="0.00151669" ixy="-1.0799e-05" ixz="4.76345e-05" iyy="0.00139101" iyz="-0.000160415" izz="0.000479546" />
       </inertial>
       <!-- Part right_foot_parts -->
       <collision>
-        <origin xyz="0 0.05 0.015" rpy="1.5708 0 -0" />
+        <origin xyz="0.0046 0.057 -0.05998" rpy="1.5708 0 0" />
+        <geometry>
+          <sphere radius="0.008" />
+        </geometry>
+      </collision>
+      <collision>
+        <origin xyz="0.03941 0.057 -0.0259" rpy="1.5708 0 0" />
+        <geometry>
+          <sphere radius="0.008" />
+        </geometry>
+      </collision>
+      <collision>
+        <origin xyz="-0.02804 0.057 -0.02442" rpy="1.5708 0 0" />
+        <geometry>
+          <sphere radius="0.008" />
+        </geometry>
+      </collision>
+      <collision>
+        <origin xyz="0.04209 0.057 0.02764" rpy="1.5708 0 0" />
+        <geometry>
+          <sphere radius="0.008" />
+        </geometry>
+      </collision>
+      <collision>
+        <origin xyz="-0.03476 0.057 0.02877" rpy="1.5708 0 0" />
+        <geometry>
+          <sphere radius="0.008" />
+        </geometry>
+      </collision>
+      <collision>
+        <origin xyz="0.04432 0.057 0.0812" rpy="1.5708 0 0" />
+        <geometry>
+          <sphere radius="0.008" />
+        </geometry>
+      </collision>
+      <collision>
+        <origin xyz="-0.04148 0.057 0.08196" rpy="1.5708 0 0" />
+        <geometry>
+          <sphere radius="0.008" />
+        </geometry>
+      </collision>
+      <collision>
+        <origin xyz="0.00047 0.057 0.09173" rpy="1.5708 0 0" />
+        <geometry>
+          <sphere radius="0.008" />
+        </geometry>
+      </collision>
+      <collision>
+        <origin xyz="0.03438 0.04891 0.12489" rpy="1.5708 0 0" />
+        <geometry>
+          <sphere radius="0.008" />
+        </geometry>
+      </collision>
+      <collision>
+        <origin xyz="-0.03932 0.04853 0.12597" rpy="1.5708 0 0" />
         <geometry>
-          <box size="0.065 0.12 0.03" />
+          <sphere radius="0.008" />
         </geometry>
       </collision>
       <collision>
-        <origin xyz="0 0.04 0.11" rpy="1.91986 0 -0" />
+        <origin xyz="-0.00465 0.03713 0.14874" rpy="1.5708 0 0" />
         <geometry>
-          <box size="0.07 0.05 0.03" />
+          <sphere radius="0.008" />
         </geometry>
       </collision>
       <visual>
-        <origin xyz="-0.0012494 0.0227876 0.039804" rpy="1.5708 -1.5708 0" />
+        <origin xyz="0.0023746 0.0232151 0.0359757" rpy="1.5708 -1.5708 0" />
         <geometry>
           <mesh filename="${mesh_root}/right_foot_visual.stl" />
         </geometry>
@@ -406,7 +514,7 @@
     </link>
     <!-- Joint from right_ankle_pitch to right_foot -->
     <joint name="right_ankle_roll" type="revolute">
-      <origin xyz="-0 0.04 -0" rpy="-0 1.5708 0" />
+      <origin xyz="0 0.04 0" rpy="0 1.5708 0" />
       <parent link="right_ankle_pitch" />
       <child link="right_foot" />
       <axis xyz="0 0 1" />
@@ -415,7 +523,7 @@
     </joint>
     <!-- Joint from right_ankle_yaw to right_ankle_pitch -->
     <joint name="right_ankle_pitch" type="revolute">
-      <origin xyz="0.01 0 -0.34" rpy="-1.5708 0 0" />
+      <origin xyz="0.01 0 -0.34" rpy="-1.5708 -0 -0" />
       <parent link="right_ankle_yaw" />
       <child link="right_ankle_pitch" />
       <axis xyz="0 0 1" />
@@ -424,7 +532,7 @@
     </joint>
     <!-- Joint from right_knee_pitch to right_ankle_yaw -->
     <joint name="right_ankle_yaw" type="revolute">
-      <origin xyz="-0.015 0 -0" rpy="1.5708 -0 -0" />
+      <origin xyz="-0.015 0 0" rpy="1.5708 -0 -0" />
       <parent link="right_knee_pitch" />
       <child link="right_ankle_yaw" />
       <axis xyz="0 0 1" />
@@ -442,7 +550,7 @@
     </joint>
     <!-- Joint from right_hip_roll to right_hip_yaw -->
     <joint name="right_hip_yaw" type="revolute">
-      <origin xyz="-0 -0.0068404 -0.0187939" rpy="0 -1.22173 1.5708" />
+      <origin xyz="-0 -0.0068404 -0.0187939" rpy="-0 -1.22173 1.5708" />
       <parent link="right_hip_roll" />
       <child link="right_hip_yaw" />
       <axis xyz="0 0 1" />
diff --git a/robots/lite_biped/xacro/lite_biped.ros2_control.xacro b/robots/lite_biped/xacro/lite_biped.ros2_control.xacro
index 73ca457..b21bb56 100644
--- a/robots/lite_biped/xacro/lite_biped.ros2_control.xacro
+++ b/robots/lite_biped/xacro/lite_biped.ros2_control.xacro
@@ -7,7 +7,10 @@
   <xacro:macro name="lite_biped_joint"
                params="name can_id model direction
                        lower_limit upper_limit torque_limit current_limit
-                       use_fake_hardware use_sim">
+                       use_fake_hardware use_sim
+                       use_linkage:=true linkage_ground:=0
+                       linkage_crank_in:=0 linkage_coupler:=0 linkage_crank_out:=0
+                       linkage_alpha_zero:=0 linkage_sign:=1">
     <joint name="${name}">
       <command_interface name="position"/>
       <command_interface name="velocity"/>
@@ -25,11 +28,30 @@
         <param name="upper_limit">${upper_limit}</param>
         <param name="torque_limit">${torque_limit}</param>
         <param name="current_limit">${current_limit}</param>
+        <!-- Four-bar transmission geometry, for joints that declare one in
+             ros2_control.json. The geometry is a PHYSICAL FACT so it is always
+             published: calibrate_robot reads it from /robot_description to refer
+             the URDF joint limits into actuator space, even on the runs where the
+             hardware plugin must NOT apply the transform. `linkage_enabled`
+             (= the use_linkage arg) is what switches the plugin's behaviour:
+             false during calibration, which needs raw actuator angles. With it
+             true, RobstrideSystem converts joint<->actuator through the linkage
+             and refers the commanded impedance by J^2, so /joint_states and every
+             controller speak true joint space. -->
+        <xacro:if value="${linkage_ground > 0}">
+          <param name="linkage_ground">${linkage_ground}</param>
+          <param name="linkage_crank_in">${linkage_crank_in}</param>
+          <param name="linkage_coupler">${linkage_coupler}</param>
+          <param name="linkage_crank_out">${linkage_crank_out}</param>
+          <param name="linkage_alpha_zero">${linkage_alpha_zero}</param>
+          <param name="linkage_sign">${linkage_sign}</param>
+          <param name="linkage_enabled">${use_linkage}</param>
+        </xacro:if>
       </xacro:unless>
     </joint>
   </xacro:macro>
 
-  <xacro:macro name="lite_biped_left_leg_joints" params="use_fake_hardware use_sim">
+  <xacro:macro name="lite_biped_left_leg_joints" params="use_fake_hardware use_sim use_linkage:=true">
     <xacro:lite_biped_joint name="left_hip_pitch" can_id="31" model="rs-06" direction="-1"
                       lower_limit="-2.35619" upper_limit="0.785398"
                       torque_limit="36.0" current_limit="43"
@@ -53,14 +75,18 @@
     <xacro:lite_biped_joint name="left_ankle_pitch" can_id="36" model="rs-00" direction="1"
                       lower_limit="-0.523599" upper_limit="0.872665"
                       torque_limit="14.0" current_limit="16"
-                      use_fake_hardware="${use_fake_hardware}" use_sim="${use_sim}"/>
+                      use_fake_hardware="${use_fake_hardware}" use_sim="${use_sim}"
+                      linkage_ground="160.449369" linkage_crank_in="40.0"
+                      linkage_coupler="150.0" linkage_crank_out="40.0"
+                      linkage_alpha_zero="338.82213" linkage_sign="1"
+                      use_linkage="${use_linkage}"/>
     <xacro:lite_biped_joint name="left_ankle_roll" can_id="37" model="rs-05" direction="-1"
                       lower_limit="-0.349066" upper_limit="0.349066"
                       torque_limit="5.5" current_limit="14"
                       use_fake_hardware="${use_fake_hardware}" use_sim="${use_sim}"/>
   </xacro:macro>
 
-  <xacro:macro name="lite_biped_right_leg_joints" params="use_fake_hardware use_sim">
+  <xacro:macro name="lite_biped_right_leg_joints" params="use_fake_hardware use_sim use_linkage:=true">
     <xacro:lite_biped_joint name="right_hip_pitch" can_id="41" model="rs-06" direction="1"
                       lower_limit="-2.35619" upper_limit="0.785398"
                       torque_limit="36.0" current_limit="43"
@@ -84,7 +110,11 @@
     <xacro:lite_biped_joint name="right_ankle_pitch" can_id="46" model="rs-00" direction="-1"
                       lower_limit="-0.523599" upper_limit="0.872665"
                       torque_limit="14.0" current_limit="16"
-                      use_fake_hardware="${use_fake_hardware}" use_sim="${use_sim}"/>
+                      use_fake_hardware="${use_fake_hardware}" use_sim="${use_sim}"
+                      linkage_ground="160.449369" linkage_crank_in="40.0"
+                      linkage_coupler="150.0" linkage_crank_out="40.0"
+                      linkage_alpha_zero="338.82213" linkage_sign="1"
+                      use_linkage="${use_linkage}"/>
     <xacro:lite_biped_joint name="right_ankle_roll" can_id="47" model="rs-05" direction="-1"
                       lower_limit="-0.349066" upper_limit="0.349066"
                       torque_limit="5.5" current_limit="14"
@@ -125,14 +155,14 @@
        sensor). The controller_manager runs them concurrently and exposes a
        single flat joint list to controllers. -->
   <xacro:macro name="lite_biped_ros2_control_real"
-               params="mode can_interface_left can_interface_right calibration_file imu_port">
+               params="mode can_interface_left can_interface_right calibration_file imu_port use_linkage">
     <ros2_control name="LiteBipedLeftLeg" type="system">
       <hardware>
         <plugin>humanoid_devices_robstride/RobstrideSystem</plugin>
         <param name="can_interface">${can_interface_left}</param>
         <param name="calibration_file">${calibration_file}</param>
       </hardware>
-      <xacro:lite_biped_left_leg_joints use_fake_hardware="false" use_sim="false"/>
+      <xacro:lite_biped_left_leg_joints use_fake_hardware="false" use_sim="false" use_linkage="${use_linkage}"/>
     </ros2_control>
     <ros2_control name="LiteBipedRightLeg" type="system">
       <hardware>
@@ -140,7 +170,7 @@
         <param name="can_interface">${can_interface_right}</param>
         <param name="calibration_file">${calibration_file}</param>
       </hardware>
-      <xacro:lite_biped_right_leg_joints use_fake_hardware="false" use_sim="false"/>
+      <xacro:lite_biped_right_leg_joints use_fake_hardware="false" use_sim="false" use_linkage="${use_linkage}"/>
     </ros2_control>
     <ros2_control name="LiteBipedIMU" type="sensor">
       <hardware>
@@ -166,7 +196,7 @@
        (use_sim wins over use_fake_hardware, matching franka_ros2 / UR precedence). -->
   <xacro:macro name="lite_biped_ros2_control"
                params="name use_fake_hardware use_sim mode
-                       can_interface_left can_interface_right calibration_file imu_port">
+                       can_interface_left can_interface_right calibration_file imu_port use_linkage">
     <xacro:if value="${use_sim or use_fake_hardware}">
       <xacro:lite_biped_ros2_control_combined name="${name}"
         use_fake_hardware="${use_fake_hardware}" use_sim="${use_sim}"/>
@@ -176,7 +206,8 @@
         can_interface_left="${can_interface_left}"
         can_interface_right="${can_interface_right}"
         calibration_file="${calibration_file}"
-        imu_port="${imu_port}"/>
+        imu_port="${imu_port}"
+        use_linkage="${use_linkage}"/>
     </xacro:unless>
   </xacro:macro>
 
diff --git a/robots/lite_biped/xacro/lite_biped.urdf.xacro b/robots/lite_biped/xacro/lite_biped.urdf.xacro
index e3537a4..b4883f0 100644
--- a/robots/lite_biped/xacro/lite_biped.urdf.xacro
+++ b/robots/lite_biped/xacro/lite_biped.urdf.xacro
@@ -8,6 +8,7 @@
   <xacro:arg name="can_interface_right" default="can3"/>
   <xacro:arg name="calibration_file" default=""/>
   <xacro:arg name="imu_port" default="/dev/ttyUSB0"/>
+  <xacro:arg name="use_linkage" default="true"/>
 
   <xacro:include filename="$(find lite_description)/robots/lite_biped/xacro/lite_biped.description.xacro"/>
   <xacro:include filename="$(find lite_description)/robots/lite_biped/xacro/lite_biped.ros2_control.xacro"/>
@@ -22,5 +23,6 @@
     can_interface_left="$(arg can_interface_left)"
     can_interface_right="$(arg can_interface_right)"
     calibration_file="$(arg calibration_file)"
-    imu_port="$(arg imu_port)"/>
+    imu_port="$(arg imu_port)"
+    use_linkage="$(arg use_linkage)"/>
 </robot>
diff --git a/robots/lite_dummy/mjcf/lite_dummy.xml b/robots/lite_dummy/mjcf/lite_dummy.xml
index e51ec36..b5cb98f 100644
--- a/robots/lite_dummy/mjcf/lite_dummy.xml
+++ b/robots/lite_dummy/mjcf/lite_dummy.xml
@@ -133,4 +133,4 @@
       </body>
     </body>
   </worldbody>
-<actuator><motor name="left_shoulder_pitch" joint="left_shoulder_pitch" forcerange="-17 17" /><motor name="left_shoulder_roll" joint="left_shoulder_roll" forcerange="-14 14" /><motor name="left_shoulder_yaw" joint="left_shoulder_yaw" forcerange="-14 14" /><motor name="left_elbow_pitch" joint="left_elbow_pitch" forcerange="-14 14" /><motor name="left_wrist_yaw" joint="left_wrist_yaw" forcerange="-5.5 5.5" /><motor name="left_wrist_roll" joint="left_wrist_roll" forcerange="-5.5 5.5" /><motor name="left_wrist_pitch" joint="left_wrist_pitch" forcerange="-5.5 5.5" /><motor name="right_shoulder_pitch" joint="right_shoulder_pitch" forcerange="-17 17" /><motor name="right_shoulder_roll" joint="right_shoulder_roll" forcerange="-14 14" /><motor name="right_shoulder_yaw" joint="right_shoulder_yaw" forcerange="-14 14" /><motor name="right_elbow_pitch" joint="right_elbow_pitch" forcerange="-14 14" /><motor name="right_wrist_yaw" joint="right_wrist_yaw" forcerange="-5.5 5.5" /><motor name="right_wrist_roll" joint="right_wrist_roll" forcerange="-5.5 5.5" /><motor name="right_wrist_pitch" joint="right_wrist_pitch" forcerange="-5.5 5.5" /><motor name="neck_yaw" joint="neck_yaw" forcerange="-10 10" /><motor name="neck_roll" joint="neck_roll" forcerange="-10 10" /><motor name="neck_pitch" joint="neck_pitch" forcerange="-10 10" /></actuator></mujoco>
\ No newline at end of file
+<actuator><position name="left_shoulder_pitch" joint="left_shoulder_pitch" forcerange="-17 17" /><position name="left_shoulder_roll" joint="left_shoulder_roll" forcerange="-14 14" /><position name="left_shoulder_yaw" joint="left_shoulder_yaw" forcerange="-14 14" /><position name="left_elbow_pitch" joint="left_elbow_pitch" forcerange="-14 14" /><position name="left_wrist_yaw" joint="left_wrist_yaw" forcerange="-5.5 5.5" /><position name="left_wrist_roll" joint="left_wrist_roll" forcerange="-5.5 5.5" /><position name="left_wrist_pitch" joint="left_wrist_pitch" forcerange="-5.5 5.5" /><position name="right_shoulder_pitch" joint="right_shoulder_pitch" forcerange="-17 17" /><position name="right_shoulder_roll" joint="right_shoulder_roll" forcerange="-14 14" /><position name="right_shoulder_yaw" joint="right_shoulder_yaw" forcerange="-14 14" /><position name="right_elbow_pitch" joint="right_elbow_pitch" forcerange="-14 14" /><position name="right_wrist_yaw" joint="right_wrist_yaw" forcerange="-5.5 5.5" /><position name="right_wrist_roll" joint="right_wrist_roll" forcerange="-5.5 5.5" /><position name="right_wrist_pitch" joint="right_wrist_pitch" forcerange="-5.5 5.5" /><position name="neck_yaw" joint="neck_yaw" forcerange="-10 10" /><position name="neck_roll" joint="neck_roll" forcerange="-10 10" /><position name="neck_pitch" joint="neck_pitch" forcerange="-10 10" /></actuator></mujoco>
\ No newline at end of file
diff --git a/tests/test_urdf_to_mjcf.py b/tests/test_urdf_to_mjcf.py
index 879b193..e138cd2 100644
--- a/tests/test_urdf_to_mjcf.py
+++ b/tests/test_urdf_to_mjcf.py
@@ -79,7 +79,7 @@ def test_committed_mjcf_loads_and_sensors_are_site_backed(mjcf_path):
         )
 
 
-def test_add_actuators_emits_motors_and_no_sensors(tmp_path):
+def test_add_actuators_emits_position_actuators_and_no_sensors(tmp_path):
     xml_path = tmp_path / "robot.xml"
     xml_path.write_text(
         """<?xml version="1.0"?>
@@ -98,6 +98,9 @@ def test_add_actuators_emits_motors_and_no_sensors(tmp_path):
 
     root = ET.parse(xml_path).getroot()
     assert root.find("sensor") is None
-    motors = root.findall("./actuator/motor")
-    assert [m.get("name") for m in motors] == ["j1"]
-    assert motors[0].get("forcerange") == "-5 5"
+    # <position>, not <motor>: the joint PD is evaluated every mj_step inside the
+    # physics model rather than sampled once per controller_manager tick.
+    actuators = root.findall("./actuator/position")
+    assert root.findall("./actuator/motor") == []
+    assert [a.get("name") for a in actuators] == ["j1"]
+    assert actuators[0].get("forcerange") == "-5 5"