From 14319ee6083808e4a300a61e81f20522f743c752 Mon Sep 17 00:00:00 2001
From: pepijn kooijmans <pepijn@huggingface.co>
Date: Fri, 21 Nov 2025 11:48:52 +0100
Subject: [PATCH] add openarms mini

---
 examples/openarms/teleop_openarms_mini.py     |  10 +-
 examples/openarms_web_interface/App.jsx       | 127 ++++-
 .../web_record_server.py                      | 484 +++++++++++++-----
 3 files changed, 466 insertions(+), 155 deletions(-)

diff --git a/examples/openarms/teleop_openarms_mini.py b/examples/openarms/teleop_openarms_mini.py
index e05a148ad..9faf0c90d 100644
--- a/examples/openarms/teleop_openarms_mini.py
+++ b/examples/openarms/teleop_openarms_mini.py
@@ -39,9 +39,9 @@ follower_config = OpenArmsFollowerConfig(
 
 # Configure the OpenArms Mini leader (Feetech motors on serial)
 leader_config = OpenArmsMiniConfig(
-    port_right="/dev/ttyACM0",  # Serial port for right arm
-    port_left="/dev/ttyACM1",   # Serial port for left arm
-    id="openarms_minis",
+    port_right="/dev/ttyACM1",  # Serial port for right arm
+    port_left="/dev/ttyACM0",   # Serial port for left arm
+    id="openarms_mini",
     use_degrees=True,
 )
 
@@ -131,8 +131,6 @@ try:
             # Determine which follower joint this leader joint controls
             follower_joint = SWAPPED_JOINTS.get(joint, joint)
             follower_key = f"{follower_joint}.pos"
-            if "left" in follower_key:
-                 continue
 
             # Get leader position (default 0 if missing)
             pos = leader_action.get(leader_key, 0.0)
@@ -149,7 +147,7 @@ try:
             # Store in action dict for follower
             joint_action[follower_key] = pos
 
-        #follower.send_action(joint_action)
+        follower.send_action(joint_action)
 
         # Loop timing
         loop_end = time.perf_counter()
diff --git a/examples/openarms_web_interface/App.jsx b/examples/openarms_web_interface/App.jsx
index 6342b5551..662eb57e3 100644
--- a/examples/openarms_web_interface/App.jsx
+++ b/examples/openarms_web_interface/App.jsx
@@ -24,6 +24,7 @@ function App() {
 
   // Configuration
   const [config, setConfig] = useState({
+    leader_type: 'openarms',  // 'openarms' or 'openarms_mini'
     leader_left: 'can0',
     leader_right: 'can1',
     follower_left: 'can2',
@@ -35,6 +36,7 @@ function App() {
 
   // Available options
   const [availableCameras, setAvailableCameras] = useState([]);
+  const [availableUsbPorts, setAvailableUsbPorts] = useState([]);
   const canInterfaces = ['can0', 'can1', 'can2', 'can3'];
 
   const statusIntervalRef = useRef(null);
@@ -192,6 +194,43 @@ function App() {
     }
   };
 
+  // Discover USB ports
+  const discoverUsbPorts = async () => {
+    try {
+      const response = await fetch(`${API_BASE}/usb/discover`);
+      const data = await response.json();
+      const ports = data.ports || [];
+      setAvailableUsbPorts(ports);
+
+      // Auto-fix config if OpenArms Mini is selected and ports are invalid
+      if (config.leader_type === 'openarms_mini') {
+        const updated = { ...config };
+        let changed = false;
+
+        if (ports.length >= 1 && !ports.includes(config.leader_left)) {
+          updated.leader_left = ports[0];
+          changed = true;
+        }
+
+        if (ports.length >= 2 && !ports.includes(config.leader_right)) {
+          updated.leader_right = ports[1];
+          changed = true;
+        }
+
+        if (changed) {
+          setConfig(updated);
+          saveConfig(updated);
+        }
+      }
+
+      if (ports.length === 0) {
+        console.warn('No USB ports detected for OpenArms Mini');
+      }
+    } catch (e) {
+      console.error('Failed to discover USB ports:', e);
+    }
+  };
+
   // Set task only (for pedal use)
   const setTaskOnly = async () => {
     if (!task.trim()) {
@@ -324,6 +363,7 @@ function App() {
 
     loadConfig();
     discoverCameras();
+    discoverUsbPorts();
     fetchStatus();
     statusIntervalRef.current = setInterval(fetchStatus, 1000);
 
@@ -335,6 +375,14 @@ function App() {
     // eslint-disable-next-line react-hooks/exhaustive-deps
   }, []); // Run only once on mount
 
+  // Discover USB ports when leader type changes to Mini
+  useEffect(() => {
+    if (config.leader_type === 'openarms_mini') {
+      discoverUsbPorts();
+    }
+    // eslint-disable-next-line react-hooks/exhaustive-deps
+  }, [config.leader_type]);
+
   return (
     <main>
       <header>
@@ -385,9 +433,42 @@ function App() {
                 </div>
               </div>
 
-              {/* CAN Interfaces */}
+              {/* Leader Type Selection */}
               <div className="config-section">
-                <h3>CAN Interfaces</h3>
+                <h3>🎮 Leader Type</h3>
+                <div className="config-grid">
+                  <label style={{gridColumn: '1 / -1'}}>
+                    Leader Arm Type
+                    <select
+                      value={config.leader_type}
+                      onChange={(e) => updateConfig('leader_type', e.target.value)}
+                      disabled={isRecording || robotsReady}
+                    >
+                      <option value="openarms">OpenArms (CAN Bus - Damiao Motors)</option>
+                      <option value="openarms_mini">OpenArms Mini (USB - Feetech Motors)</option>
+                    </select>
+                  </label>
+                </div>
+              </div>
+
+              {/* Leader Interfaces (CAN or USB based on type) */}
+              <div className="config-section">
+                <div style={{ display: 'flex', justifyContent: 'space-between', alignItems: 'center', marginBottom: '0.5rem' }}>
+                  <h3>
+                    {config.leader_type === 'openarms_mini' 
+                      ? `Leader Ports (USB) ${availableUsbPorts.length > 0 ? `(${availableUsbPorts.length} detected)` : ''}` 
+                      : 'Leader Interfaces (CAN)'}
+                  </h3>
+                  {config.leader_type === 'openarms_mini' && (
+                    <button
+                      onClick={discoverUsbPorts}
+                      className="btn-refresh"
+                      disabled={isRecording || robotsReady}
+                    >
+                      🔄 Refresh
+                    </button>
+                  )}
+                </div>
                 <div className="config-grid">
                   <label>
                     Leader Left
@@ -396,9 +477,19 @@ function App() {
                       onChange={(e) => updateConfig('leader_left', e.target.value)}
                       disabled={isRecording || robotsReady}
                     >
-                      {canInterfaces.map((iface) => (
-                        <option key={iface} value={iface}>{iface}</option>
-                      ))}
+                      {config.leader_type === 'openarms_mini' ? (
+                        availableUsbPorts.length > 0 ? (
+                          availableUsbPorts.map((port) => (
+                            <option key={port} value={port}>{port}</option>
+                          ))
+                        ) : (
+                          <option value="">No USB ports detected</option>
+                        )
+                      ) : (
+                        canInterfaces.map((iface) => (
+                          <option key={iface} value={iface}>{iface}</option>
+                        ))
+                      )}
                     </select>
                   </label>
 
@@ -409,12 +500,28 @@ function App() {
                       onChange={(e) => updateConfig('leader_right', e.target.value)}
                       disabled={isRecording || robotsReady}
                     >
-                      {canInterfaces.map((iface) => (
-                        <option key={iface} value={iface}>{iface}</option>
-                      ))}
+                      {config.leader_type === 'openarms_mini' ? (
+                        availableUsbPorts.length > 0 ? (
+                          availableUsbPorts.map((port) => (
+                            <option key={port} value={port}>{port}</option>
+                          ))
+                        ) : (
+                          <option value="">No USB ports detected</option>
+                        )
+                      ) : (
+                        canInterfaces.map((iface) => (
+                          <option key={iface} value={iface}>{iface}</option>
+                        ))
+                      )}
                     </select>
                   </label>
+                </div>
+              </div>
 
+              {/* Follower CAN Interfaces */}
+              <div className="config-section">
+                <h3>Follower Interfaces (CAN)</h3>
+                <div className="config-grid">
                   <label>
                     Follower Left
                     <select
@@ -627,9 +734,9 @@ function App() {
                 onClick={moveToZero} 
                 disabled={movingToZero}
                 className="btn-zero-large"
-                title="Move follower robot to zero position (2s with 60% gains)"
+                title="Move both leader and follower robots to zero position (2s)"
               >
-                {movingToZero ? '⏳ Moving to Zero Position...' : '🎯 Move to Zero Position'}
+                {movingToZero ? '⏳ Moving to Zero Position...' : '🎯 Move to Zero Position (Leader + Follower)'}
               </button>
             </div>
           )}
diff --git a/examples/openarms_web_interface/web_record_server.py b/examples/openarms_web_interface/web_record_server.py
index f20e56df8..0cc9b45c4 100644
--- a/examples/openarms_web_interface/web_record_server.py
+++ b/examples/openarms_web_interface/web_record_server.py
@@ -37,6 +37,8 @@ from lerobot.robots.openarms.config_openarms_follower import OpenArmsFollowerCon
 from lerobot.robots.openarms.openarms_follower import OpenArmsFollower
 from lerobot.teleoperators.openarms.config_openarms_leader import OpenArmsLeaderConfig
 from lerobot.teleoperators.openarms.openarms_leader import OpenArmsLeader
+from lerobot.teleoperators.openarms_mini.config_openarms_mini import OpenArmsMiniConfig
+from lerobot.teleoperators.openarms_mini.openarms_mini import OpenArmsMini
 
 app = FastAPI(title="OpenArms Recording Server")
 
@@ -68,6 +70,7 @@ recording_state = {
     "recording_started_time": None,  # Time when actual recording starts (after ramp-up)
     "moving_to_zero": False,  # Whether robot is moving to zero position
     "config": {
+        "leader_type": "openarms",  # "openarms" or "openarms_mini"
         "leader_left": "can0",
         "leader_right": "can1",
         "follower_left": "can2",
@@ -108,6 +111,28 @@ FPS = 30
 FRICTION_SCALE = 1.0
 RAMP_UP_DURATION = 3.0  # Seconds to ramp up PID/torque from 0 to full
 
+# OpenArms Mini joint mappings (from teleop_openarms_mini.py)
+JOINT_DIRECTION_MINI = {
+    "right_joint_1": -1,
+    "right_joint_2": -1,
+    "right_joint_3": -1,
+    "right_joint_4": -1,
+    "right_joint_5": -1,
+    "left_joint_1": -1,
+    "left_joint_3": -1,
+    "left_joint_4": -1,
+    "left_joint_5": -1,
+    "left_joint_6": -1,
+    "left_joint_7": -1,
+}
+
+SWAPPED_JOINTS_MINI = {
+    "right_joint_6": "right_joint_7",
+    "right_joint_7": "right_joint_6",
+    "left_joint_6": "left_joint_7",
+    "left_joint_7": "left_joint_6",
+}
+
 # Pedal configuration
 PEDAL_DEVICE = "/dev/input/by-id/usb-PCsensor_FootSwitch-event-kbd"
 PEDAL_ENABLED = True  # Set to False to disable pedal
@@ -118,6 +143,7 @@ pedal_action_lock = threading.Lock()  # Prevent concurrent pedal actions
 
 class RecordingConfig(BaseModel):
     task: str
+    leader_type: str  # "openarms" or "openarms_mini"
     leader_left: str
     leader_right: str
     follower_left: str
@@ -129,6 +155,7 @@ class RecordingConfig(BaseModel):
 
 class RobotSetupConfig(BaseModel):
     """Configuration for robot setup (no task required)."""
+    leader_type: str  # "openarms" or "openarms_mini"
     leader_left: str
     leader_right: str
     follower_left: str
@@ -154,6 +181,31 @@ def discover_cameras_sync():
         return []
 
 
+def discover_usb_ports_sync():
+    """Discover available USB/serial ports for OpenArms Mini."""
+    try:
+        import glob
+        import serial
+        # Find all USB serial devices
+        ports = []
+        for pattern in ["/dev/ttyUSB*", "/dev/ttyACM*"]:
+            for port in glob.glob(pattern):
+                # Check if port is accessible
+                try:
+                    # Try to open and close the port to verify access
+                    ser = serial.Serial(port, timeout=0.1)
+                    ser.close()
+                    ports.append(port)
+                except (OSError, serial.SerialException) as e:
+                    print(f"[USB] Port {port} exists but not accessible: {e}")
+        ports.sort()
+        print(f"[USB] Found {len(ports)} accessible USB port(s): {ports}")
+        return ports
+    except Exception as e:
+        print(f"[USB] Error: {e}")
+        return []
+
+
 @app.get("/api/cameras/discover")
 async def discover_cameras():
     """Discover available cameras."""
@@ -161,6 +213,30 @@ async def discover_cameras():
     return {"cameras": cameras}
 
 
+@app.get("/api/usb/discover")
+async def discover_usb_ports():
+    """Discover available USB/serial ports."""
+    ports = discover_usb_ports_sync()
+    return {"ports": ports}
+
+
+@app.get("/api/usb/test/{port:path}")
+async def test_usb_port(port: str):
+    """Test if a USB port is accessible."""
+    try:
+        import serial
+        print(f"[USB Test] Testing port: {port}")
+        ser = serial.Serial(port, baudrate=1000000, timeout=0.1)
+        ser.close()
+        return {"status": "success", "message": f"Port {port} is accessible"}
+    except PermissionError as e:
+        return {"status": "error", "message": f"Permission denied: {e}"}
+    except serial.SerialException as e:
+        return {"status": "error", "message": f"Serial error: {e}"}
+    except Exception as e:
+        return {"status": "error", "message": f"Error: {e}"}
+
+
 @app.get("/api/can/interfaces")
 async def get_can_interfaces():
     """Get available CAN interfaces."""
@@ -171,7 +247,9 @@ def initialize_robots_only(config: RobotSetupConfig):
     """Initialize robots only (no dataset) for pre-setup."""
     global robot_instances, recording_state
     
-    print(f"[Setup] Initializing robots...")
+    print(f"[Setup] Initializing robots with leader type: {config.leader_type}")
+    print(f"[Setup] Leader ports: left={config.leader_left}, right={config.leader_right}")
+    print(f"[Setup] Follower ports: left={config.follower_left}, right={config.follower_right}")
 
     # Update status: Configuring cameras
     recording_state["status_message"] = "Configuring cameras..."
@@ -183,6 +261,7 @@ def initialize_robots_only(config: RobotSetupConfig):
 
     # Configure follower robot with cameras
     recording_state["status_message"] = "Configuring follower robot..."
+    print(f"[Setup] Configuring follower with CAN: {config.follower_left}, {config.follower_right}")
     follower_config = OpenArmsFollowerConfig(
         port_left=config.follower_left,
         port_right=config.follower_right,
@@ -193,38 +272,68 @@ def initialize_robots_only(config: RobotSetupConfig):
         cameras=camera_config,
     )
 
-    # Configure leader teleoperator
+    # Configure leader teleoperator based on type
     recording_state["status_message"] = "Configuring leader teleoperator..."
-    leader_config = OpenArmsLeaderConfig(
-        port_left=config.leader_left,
-        port_right=config.leader_right,
-        can_interface="socketcan",
-        id="openarms_leader",
-        manual_control=False,
-    )
+    if config.leader_type == "openarms_mini":
+        # OpenArms Mini: USB/serial ports, Feetech motors
+        leader_config = OpenArmsMiniConfig(
+            port_left=config.leader_left,
+            port_right=config.leader_right,
+            id="openarms_mini",
+            use_degrees=True,
+        )
+        leader = OpenArmsMini(leader_config)
+    else:
+        # OpenArms: CAN bus, Damiao motors
+        leader_config = OpenArmsLeaderConfig(
+            port_left=config.leader_left,
+            port_right=config.leader_right,
+            can_interface="socketcan",
+            id="openarms_leader",
+            manual_control=False,
+        )
+        leader = OpenArmsLeader(leader_config)
 
     # Initialize and connect
     recording_state["status_message"] = "Connecting to follower robot..."
     follower = OpenArmsFollower(follower_config)
-    follower.connect(calibrate=False)  # Skip calibration in web mode
+    try:
+        follower.connect(calibrate=False)  # Skip calibration in web mode
+    except Exception as e:
+        print(f"[Setup] Follower connection error: {e}")
+        raise RuntimeError(f"Failed to connect to follower robot: {e}")
 
     recording_state["status_message"] = "Connecting to leader teleoperator..."
-    leader = OpenArmsLeader(leader_config)
-    leader.connect(calibrate=False)
+    try:
+        leader.connect(calibrate=False)
+    except Exception as e:
+        print(f"[Setup] Leader connection error: {e}")
+        # Disconnect follower on leader connection failure
+        try:
+            follower.disconnect()
+        except:
+            pass
+        raise RuntimeError(f"Failed to connect to leader teleoperator: {e}")
 
-    # Verify URDF is loaded
-    recording_state["status_message"] = "Loading URDF model for gravity compensation..."
-    if leader.pin_robot is None:
-        raise RuntimeError("URDF model not loaded on leader. Gravity compensation not available.")
-
-    # Enable gravity compensation
-    recording_state["status_message"] = "Enabling gravity compensation..."
-    leader.bus_right.enable_torque()
-    leader.bus_left.enable_torque()
-    time.sleep(0.1)
+    # Enable torque/gravity compensation based on leader type
+    if config.leader_type == "openarms":
+        # Verify URDF is loaded for OpenArms (needs gravity compensation)
+        recording_state["status_message"] = "Loading URDF model for gravity compensation..."
+        if leader.pin_robot is None:
+            raise RuntimeError("URDF model not loaded on leader. Gravity compensation not available.")
+        
+        # Enable gravity compensation
+        recording_state["status_message"] = "Enabling gravity compensation..."
+        leader.bus_right.enable_torque()
+        leader.bus_left.enable_torque()
+        time.sleep(0.1)
+    else:
+        # OpenArms Mini: No gravity compensation needed (Feetech motors)
+        recording_state["status_message"] = "Leader ready (no gravity compensation needed)..."
 
     robot_instances["follower"] = follower
     robot_instances["leader"] = leader
+    robot_instances["leader_type"] = config.leader_type
 
 
 def initialize_robot_systems(config: RecordingConfig):
@@ -259,15 +368,27 @@ def initialize_robot_systems(config: RecordingConfig):
             cameras=camera_config,
         )
 
-        # Configure leader teleoperator
+        # Configure leader teleoperator based on type
         recording_state["status_message"] = "Configuring leader teleoperator..."
-        leader_config = OpenArmsLeaderConfig(
-            port_left=config.leader_left,
-            port_right=config.leader_right,
-            can_interface="socketcan",
-            id="openarms_leader",
-            manual_control=False,
-        )
+        if config.leader_type == "openarms_mini":
+            # OpenArms Mini: USB/serial ports, Feetech motors
+            leader_config = OpenArmsMiniConfig(
+                port_left=config.leader_left,
+                port_right=config.leader_right,
+                id="openarms_mini",
+                use_degrees=True,
+            )
+            leader = OpenArmsMini(leader_config)
+        else:
+            # OpenArms: CAN bus, Damiao motors
+            leader_config = OpenArmsLeaderConfig(
+                port_left=config.leader_left,
+                port_right=config.leader_right,
+                can_interface="socketcan",
+                id="openarms_leader",
+                manual_control=False,
+            )
+            leader = OpenArmsLeader(leader_config)
 
         # Initialize and connect
         recording_state["status_message"] = "Connecting to follower robot..."
@@ -275,19 +396,25 @@ def initialize_robot_systems(config: RecordingConfig):
         follower.connect(calibrate=False)  # Skip calibration in web mode
 
         recording_state["status_message"] = "Connecting to leader teleoperator..."
-        leader = OpenArmsLeader(leader_config)
         leader.connect(calibrate=False)
 
-        # Verify URDF is loaded
-        recording_state["status_message"] = "Loading URDF model for gravity compensation..."
-        if leader.pin_robot is None:
-            raise RuntimeError("URDF model not loaded on leader. Gravity compensation not available.")
-
-        # Enable gravity compensation
-        recording_state["status_message"] = "Enabling gravity compensation..."
-        leader.bus_right.enable_torque()
-        leader.bus_left.enable_torque()
-        time.sleep(0.1)
+        # Enable torque/gravity compensation based on leader type
+        if config.leader_type == "openarms":
+            # Verify URDF is loaded for OpenArms (needs gravity compensation)
+            recording_state["status_message"] = "Loading URDF model for gravity compensation..."
+            if leader.pin_robot is None:
+                raise RuntimeError("URDF model not loaded on leader. Gravity compensation not available.")
+            
+            # Enable gravity compensation
+            recording_state["status_message"] = "Enabling gravity compensation..."
+            leader.bus_right.enable_torque()
+            leader.bus_left.enable_torque()
+            time.sleep(0.1)
+        else:
+            # OpenArms Mini: No gravity compensation needed (Feetech motors)
+            recording_state["status_message"] = "Leader ready (no gravity compensation needed)..."
+        
+        robot_instances["leader_type"] = config.leader_type
 
     # Configure dataset features
     recording_state["status_message"] = "Configuring dataset features..."
@@ -369,13 +496,14 @@ def initialize_robot_systems(config: RecordingConfig):
 
 
 def record_loop_with_compensation():
-    """Main recording loop with compensation."""
+    """Main recording loop (with or without compensation based on leader type)."""
     global recording_state, stop_recording_flag
     
     follower = robot_instances.get("follower")
     leader = robot_instances.get("leader")
     dataset = robot_instances.get("dataset")
     dataset_features = robot_instances.get("dataset_features")
+    leader_type = robot_instances.get("leader_type", "openarms")
     task = recording_state.get("task", "")
     
     # Profiling: Track time spent in each operation
@@ -398,7 +526,7 @@ def record_loop_with_compensation():
         print(f"[Recording] Error: Missing components")
         return
     
-    print(f"[Recording] Starting recording loop with ramp-up...")
+    print(f"[Recording] Starting recording loop (leader: {leader_type}) with ramp-up...")
     
     dt = 1 / FPS
     loop_start_time = time.perf_counter()
@@ -466,89 +594,116 @@ def record_loop_with_compensation():
             leader_action = leader.get_action()
             timing_stats["get_action"].append(time.perf_counter() - t0)
             
-            # Extract positions and velocities
-            leader_positions_deg = {}
-            leader_velocities_deg_per_sec = {}
-            
-            for motor in leader.bus_right.motors:
-                pos_key = f"right_{motor}.pos"
-                vel_key = f"right_{motor}.vel"
-                if pos_key in leader_action:
-                    leader_positions_deg[f"right_{motor}"] = leader_action[pos_key]
-                if vel_key in leader_action:
-                    leader_velocities_deg_per_sec[f"right_{motor}"] = leader_action[vel_key]
-            
-            for motor in leader.bus_left.motors:
-                pos_key = f"left_{motor}.pos"
-                vel_key = f"left_{motor}.vel"
-                if pos_key in leader_action:
-                    leader_positions_deg[f"left_{motor}"] = leader_action[pos_key]
-                if vel_key in leader_action:
-                    leader_velocities_deg_per_sec[f"left_{motor}"] = leader_action[vel_key]
-            
-            # Calculate gravity and friction torques
-            leader_positions_rad = {k: np.deg2rad(v) for k, v in leader_positions_deg.items()}
-            
-            t0 = time.perf_counter()
-            leader_gravity_torques_nm = leader._gravity_from_q(leader_positions_rad)
-            timing_stats["gravity_calc"].append(time.perf_counter() - t0)
-            
-            leader_velocities_rad_per_sec = {k: np.deg2rad(v) for k, v in leader_velocities_deg_per_sec.items()}
-            
-            t0 = time.perf_counter()
-            leader_friction_torques_nm = leader._friction_from_velocity(
-                leader_velocities_rad_per_sec,
-                friction_scale=FRICTION_SCALE
-            )
-            timing_stats["friction_calc"].append(time.perf_counter() - t0)
-            
-            # Combine torques
-            leader_total_torques_nm = {}
-            for motor_name in leader_gravity_torques_nm:
-                gravity = leader_gravity_torques_nm.get(motor_name, 0.0)
-                friction = leader_friction_torques_nm.get(motor_name, 0.0)
-                leader_total_torques_nm[motor_name] = gravity + friction
-            
-            # Apply compensation to RIGHT arm with ramp-up scaling
-            t0 = time.perf_counter()
-            for motor in leader.bus_right.motors:
-                full_name = f"right_{motor}"
-                position = leader_positions_deg.get(full_name, 0.0)
-                torque_raw = leader_total_torques_nm.get(full_name, 0.0)
-                # Scale torque by ramp factor during ramp-up phase
-                torque = torque_raw * ramp_factor
-                kd = leader.get_damping_kd(motor)
+            # Apply leader-specific control logic
+            if leader_type == "openarms":
+                # OpenArms: Apply gravity and friction compensation
+                # Extract positions and velocities
+                leader_positions_deg = {}
+                leader_velocities_deg_per_sec = {}
                 
-                leader.bus_right._mit_control(
-                    motor=motor, kp=0.0, kd=kd,
-                    position_degrees=position,
-                    velocity_deg_per_sec=0.0,
-                    torque=torque,
-                )
-            
-            # Apply compensation to LEFT arm with ramp-up scaling
-            for motor in leader.bus_left.motors:
-                full_name = f"left_{motor}"
-                position = leader_positions_deg.get(full_name, 0.0)
-                torque_raw = leader_total_torques_nm.get(full_name, 0.0)
-                # Scale torque by ramp factor during ramp-up phase
-                torque = torque_raw * ramp_factor
-                kd = leader.get_damping_kd(motor)
+                for motor in leader.bus_right.motors:
+                    pos_key = f"right_{motor}.pos"
+                    vel_key = f"right_{motor}.vel"
+                    if pos_key in leader_action:
+                        leader_positions_deg[f"right_{motor}"] = leader_action[pos_key]
+                    if vel_key in leader_action:
+                        leader_velocities_deg_per_sec[f"right_{motor}"] = leader_action[vel_key]
                 
-                leader.bus_left._mit_control(
-                    motor=motor, kp=0.0, kd=kd,
-                    position_degrees=position,
-                    velocity_deg_per_sec=0.0,
-                    torque=torque,
+                for motor in leader.bus_left.motors:
+                    pos_key = f"left_{motor}.pos"
+                    vel_key = f"left_{motor}.vel"
+                    if pos_key in leader_action:
+                        leader_positions_deg[f"left_{motor}"] = leader_action[pos_key]
+                    if vel_key in leader_action:
+                        leader_velocities_deg_per_sec[f"left_{motor}"] = leader_action[vel_key]
+                
+                # Calculate gravity and friction torques
+                leader_positions_rad = {k: np.deg2rad(v) for k, v in leader_positions_deg.items()}
+                
+                t0 = time.perf_counter()
+                leader_gravity_torques_nm = leader._gravity_from_q(leader_positions_rad)
+                timing_stats["gravity_calc"].append(time.perf_counter() - t0)
+                
+                leader_velocities_rad_per_sec = {k: np.deg2rad(v) for k, v in leader_velocities_deg_per_sec.items()}
+                
+                t0 = time.perf_counter()
+                leader_friction_torques_nm = leader._friction_from_velocity(
+                    leader_velocities_rad_per_sec,
+                    friction_scale=FRICTION_SCALE
                 )
-            timing_stats["leader_control"].append(time.perf_counter() - t0)
+                timing_stats["friction_calc"].append(time.perf_counter() - t0)
+                
+                # Combine torques
+                leader_total_torques_nm = {}
+                for motor_name in leader_gravity_torques_nm:
+                    gravity = leader_gravity_torques_nm.get(motor_name, 0.0)
+                    friction = leader_friction_torques_nm.get(motor_name, 0.0)
+                    leader_total_torques_nm[motor_name] = gravity + friction
+                
+                # Apply compensation to RIGHT arm with ramp-up scaling
+                t0 = time.perf_counter()
+                for motor in leader.bus_right.motors:
+                    full_name = f"right_{motor}"
+                    position = leader_positions_deg.get(full_name, 0.0)
+                    torque_raw = leader_total_torques_nm.get(full_name, 0.0)
+                    # Scale torque by ramp factor during ramp-up phase
+                    torque = torque_raw * ramp_factor
+                    kd = leader.get_damping_kd(motor)
+                    
+                    leader.bus_right._mit_control(
+                        motor=motor, kp=0.0, kd=kd,
+                        position_degrees=position,
+                        velocity_deg_per_sec=0.0,
+                        torque=torque,
+                    )
+                
+                # Apply compensation to LEFT arm with ramp-up scaling
+                for motor in leader.bus_left.motors:
+                    full_name = f"left_{motor}"
+                    position = leader_positions_deg.get(full_name, 0.0)
+                    torque_raw = leader_total_torques_nm.get(full_name, 0.0)
+                    # Scale torque by ramp factor during ramp-up phase
+                    torque = torque_raw * ramp_factor
+                    kd = leader.get_damping_kd(motor)
+                    
+                    leader.bus_left._mit_control(
+                        motor=motor, kp=0.0, kd=kd,
+                        position_degrees=position,
+                        velocity_deg_per_sec=0.0,
+                        torque=torque,
+                    )
+                timing_stats["leader_control"].append(time.perf_counter() - t0)
             
-            # Send positions to follower with ramped PID gains using send_action
+            # Build follower action from leader action
             follower_action = {}
-            for joint in all_joints:
-                pos_key = f"{joint}.pos"
-                if pos_key in leader_action:
-                    follower_action[pos_key] = leader_action[pos_key]
+            if leader_type == "openarms_mini":
+                # OpenArms Mini: Apply joint direction and swap mappings
+                for joint in all_joints:
+                    leader_key = f"{joint}.pos"
+                    
+                    # Determine which follower joint this leader joint controls
+                    follower_joint = SWAPPED_JOINTS_MINI.get(joint, joint)
+                    follower_key = f"{follower_joint}.pos"
+                    
+                    # Get leader position (default 0 if missing)
+                    pos = leader_action.get(leader_key, 0.0)
+                    
+                    # Convert gripper values: Mini uses 0-100, OpenArms uses 0 to -65 degrees
+                    if "gripper" in joint:
+                        # Map 0-100 (Mini) to 0 to -65 (OpenArms)
+                        # 0 (closed) -> 0°, 100 (open) -> -65°
+                        pos = (pos / 100.0) * -65.0
+                    else:
+                        # Apply direction reversal if specified (non-gripper joints only)
+                        pos *= JOINT_DIRECTION_MINI.get(joint, 1)
+                    
+                    follower_action[follower_key] = pos
+            else:
+                # OpenArms: Direct position mapping (no joint swapping)
+                for joint in all_joints:
+                    pos_key = f"{joint}.pos"
+                    if pos_key in leader_action:
+                        follower_action[pos_key] = leader_action[pos_key]
             
             if follower_action:
                 # Build custom ramped PID gains for all motors
@@ -742,16 +897,20 @@ def cleanup_robot_systems(keep_robots=False):
     try:
         if not keep_robots:
             if robot_instances.get("leader"):
+                leader_type = robot_instances.get("leader_type", "openarms")
+                # Only disable torque for OpenArms (with gravity compensation)
+                if leader_type == "openarms":
                     robot_instances["leader"].bus_right.disable_torque()
                     robot_instances["leader"].bus_left.disable_torque()
                     time.sleep(0.1)
-                    robot_instances["leader"].disconnect()
+                robot_instances["leader"].disconnect()
             
             if robot_instances.get("follower"):
                     robot_instances["follower"].disconnect()
             
             robot_instances["follower"] = None
             robot_instances["leader"] = None
+            robot_instances["leader_type"] = None
             recording_state["robots_ready"] = False
             print(f"[Cleanup] Robots disconnected")
         
@@ -906,39 +1065,59 @@ def do_move_to_zero(source: str = "API"):
         
         follower = robot_instances["follower"]
         leader = robot_instances.get("leader")
+        leader_type = robot_instances.get("leader_type", "openarms")
         
-        if leader:
-            print(f"[{source}] Disabling leader torque...")
+        # Handle leader based on type
+        if leader and leader_type == "openarms":
+            # OpenArms: Disable torque (with gravity compensation)
+            print(f"[{source}] Disabling leader torque (OpenArms with gravity compensation)...")
             leader.bus_right.disable_torque()
             leader.bus_left.disable_torque()
             time.sleep(0.1)
+        elif leader and leader_type == "openarms_mini":
+            # OpenArms Mini: Send to zero position command (will be executed in parallel with follower)
+            print(f"[{source}] Moving OpenArms Mini leader to zero position...")
         
         motor_index = {
             "joint_1": 0, "joint_2": 1, "joint_3": 2, "joint_4": 3,
             "joint_5": 4, "joint_6": 5, "joint_7": 6, "gripper": 7,
         }
         
-        zero_action = {}
-        custom_kp = {}
-        custom_kd = {}
+        # Prepare follower zero action
+        follower_zero_action = {}
+        follower_custom_kp = {}
+        follower_custom_kd = {}
         
         for motor in follower.bus_right.motors:
             full_name = f"right_{motor}"
-            zero_action[f"{full_name}.pos"] = 0.0
+            follower_zero_action[f"{full_name}.pos"] = 0.0
             idx = motor_index.get(motor, 0)
             kp_base = follower.config.position_kp[idx] if isinstance(follower.config.position_kp, list) else follower.config.position_kp
             kd_base = follower.config.position_kd[idx] if isinstance(follower.config.position_kd, list) else follower.config.position_kd
-            custom_kp[full_name] = kp_base * 0.05
-            custom_kd[full_name] = kd_base
+            follower_custom_kp[full_name] = kp_base * 0.05
+            follower_custom_kd[full_name] = kd_base
         
         for motor in follower.bus_left.motors:
             full_name = f"left_{motor}"
-            zero_action[f"{full_name}.pos"] = 0.0
+            follower_zero_action[f"{full_name}.pos"] = 0.0
             idx = motor_index.get(motor, 0)
             kp_base = follower.config.position_kp[idx] if isinstance(follower.config.position_kp, list) else follower.config.position_kp
             kd_base = follower.config.position_kd[idx] if isinstance(follower.config.position_kd, list) else follower.config.position_kd
-            custom_kp[full_name] = kp_base * 0.05
-            custom_kd[full_name] = kd_base
+            follower_custom_kp[full_name] = kp_base * 0.05
+            follower_custom_kd[full_name] = kd_base
+        
+        # Prepare leader zero action (for OpenArms Mini)
+        leader_zero_action = None
+        if leader and leader_type == "openarms_mini":
+            leader_zero_action = {}
+            # For OpenArms Mini, send all joints (including gripper) to zero
+            # Gripper zero = 0 (closed)
+            for motor in leader.bus_right.motors:
+                full_name = f"right_{motor}"
+                leader_zero_action[f"{full_name}.pos"] = 0.0
+            for motor in leader.bus_left.motors:
+                full_name = f"left_{motor}"
+                leader_zero_action[f"{full_name}.pos"] = 0.0
         
         duration = 2.0
         fps = 30
@@ -947,36 +1126,63 @@ def do_move_to_zero(source: str = "API"):
         
         while time.perf_counter() - start_time < duration:
             loop_start = time.perf_counter()
-            follower.send_action(zero_action, custom_kp=custom_kp, custom_kd=custom_kd)
+            
+            # Send follower to zero
+            follower.send_action(follower_zero_action, custom_kp=follower_custom_kp, custom_kd=follower_custom_kd)
+            
+            # Send leader (OpenArms Mini) to zero if applicable
+            if leader_zero_action:
+                # Use Feetech write commands directly (no custom gains needed)
+                for motor_name in leader.bus_right.motors:
+                    full_name = f"right_{motor_name}"
+                    pos_key = f"{full_name}.pos"
+                    if pos_key in leader_zero_action:
+                        # Write zero position to leader motor
+                        leader.bus_right.write("Goal_Position", motor_name, leader_zero_action[pos_key])
+                
+                for motor_name in leader.bus_left.motors:
+                    full_name = f"left_{motor_name}"
+                    pos_key = f"{full_name}.pos"
+                    if pos_key in leader_zero_action:
+                        # Write zero position to leader motor
+                        leader.bus_left.write("Goal_Position", motor_name, leader_zero_action[pos_key])
+            
             loop_duration = time.perf_counter() - loop_start
             sleep_time = dt - loop_duration
             if sleep_time > 0:
                 time.sleep(sleep_time)
         
-        if leader:
-            print(f"[{source}] Re-enabling leader torque...")
+        # Re-enable torque only for OpenArms (with gravity compensation)
+        if leader and leader_type == "openarms":
+            print(f"[{source}] Re-enabling leader torque (OpenArms with gravity compensation)...")
             leader.bus_right.enable_torque()
             leader.bus_left.enable_torque()
             time.sleep(0.1)
+        elif leader and leader_type == "openarms_mini":
+            print(f"[{source}] OpenArms Mini leader moved to zero position")
         
         recording_state["moving_to_zero"] = False
         recording_state["status_message"] = "Moved to zero position" if recording_state["robots_ready"] else "Ready"
         
-        print(f"[{source}] Move to zero complete")
-        return {"status": "success", "message": "Robot moved to zero position"}
+        print(f"[{source}] Move to zero complete (follower + leader)")
+        return {"status": "success", "message": "Robots moved to zero position"}
     
     except Exception as e:
         recording_state["moving_to_zero"] = False
         recording_state["status_message"] = f"Error: {str(e)}"
         
+        # Try to re-enable torque on error (only for OpenArms with gravity compensation)
         leader = robot_instances.get("leader")
-        if leader:
+        leader_type = robot_instances.get("leader_type", "openarms")
+        if leader and leader_type == "openarms":
             try:
+                print(f"[{source}] Attempting to re-enable leader torque after error...")
                 leader.bus_right.enable_torque()
                 leader.bus_left.enable_torque()
             except Exception as torque_error:
                 print(f"[{source}] Failed to re-enable leader torque: {torque_error}")
         
+        print(f"[{source}] Move to zero failed: {e}")
         raise HTTPException(status_code=500, detail=str(e))