Update UR5e robot configurations and UI for gripper control and home position

- Adjusted gripper control values in mujoco_server.py and UR5 environment to align with the Robotiq 2F-85 specifications (0=open, 255=closed).
- Updated the default home position for the UR5e to reflect the official MuJoCo Menagerie configuration.
- Enhanced UI elements for joint sliders and gripper display to synchronize with actual positions and improve user experience.
- Added functionality to restore saved robot selections from local storage in the UI.

mujoco_server.py

@@ -385,12 +385,11 @@ def handle_ws_message(data):
     elif msg_type == 'gripper':
         payload = data.get('data', {})
         action = payload.get('action', 'open')
-        # Robotiq 2F-85: higher control value = more open (joint angle increases)
-        # Control range 0-255 maps to joint angle 0-0.8 rad
+        # Robotiq 2F-85: 0 = open, 255 = closed (official MuJoCo Menagerie)
         if action == 'open':
-            value = 255  # 255 = fully open
+            value = 0  # 0 = fully open
         elif action == 'close':
-            value = 0  # 0 = fully closed
+            value = 255  # 255 = fully closed
         else:
             value = payload.get('value', 128)
         with mujoco_lock:
@@ -572,22 +571,21 @@ def index():
             }
             .camera-panel .control-group { margin-bottom: 10px; }
             .camera-panel .control-group:last-child { margin-bottom: 0; }
-            /* Collapsible panel header */
+            /* Collapsible panel header - title is the button */
             .panel-header {
                 display: flex; justify-content: space-between; align-items: center;
                 cursor: pointer; margin-bottom: 15px;
+                padding: 4px 0; border-radius: 4px; transition: all 0.2s;
             }
-            .panel-header h2 { margin: 0; }
-            .collapse-btn {
-                background: rgba(188, 190, 236, 0.2);
-                border: 1px solid rgba(188, 190, 236, 0.3);
-                color: var(--wb-secondary);
-                width: 28px; height: 28px;
-                border-radius: 6px; cursor: pointer;
-                display: flex; align-items: center; justify-content: center;
-                font-size: 1.1em; transition: all 0.2s;
+            .panel-header:hover { background: rgba(188, 190, 236, 0.1); }
+            .panel-header h2 {
+                margin: 0; display: flex; align-items: center; gap: 8px;
+            }
+            .panel-header h2::after {
+                content: '−'; font-weight: 300; font-size: 1.2em;
+                opacity: 0.6; transition: transform 0.2s;
             }
-            .collapse-btn:hover { background: rgba(188, 190, 236, 0.3); }
+            .panel-header.collapsed h2::after { content: '+'; }
             .panel-content { transition: all 0.3s ease; overflow: hidden; }
             .panel-content.collapsed { max-height: 0; opacity: 0; margin: 0; padding: 0; }
             .overlay.collapsed { width: auto; min-width: 200px; }
@@ -701,14 +699,12 @@ def index():
         </div>
 
         <div class="overlay" id="control_panel">
-            <div class="panel-header" onclick="togglePanel()">
+            <div class="panel-header" id="panel_header" onclick="togglePanel()">
                 <h2 id="robot_title">Unitree G1 Humanoid</h2>
-                <button class="collapse-btn" id="collapse_btn">-</button>
             </div>
 
             <div class="panel-content" id="panel_content">
                 <div class="robot-selector">
-                    <label>Select Robot</label>
                     <select id="robot_select" onchange="switchRobot()">
                         <option value="g1">Unitree G1 (Humanoid)</option>
                         <option value="spot">Boston Dynamics Spot (Quadruped)</option>
@@ -806,27 +802,27 @@ def index():
                         <div class="joint-sliders">
                             <div class="slider-row">
                                 <label>J1</label>
-                                <input type="range" id="joint_0" min="-6.28" max="6.28" step="0.01" value="0.0" oninput="updateJoints()">
-                                <span class="val-display" id="joint_0_val">0.00</span>
+                                <input type="range" id="joint_0" min="-6.28" max="6.28" step="0.01" value="-1.5708" oninput="updateJoints()">
+                                <span class="val-display" id="joint_0_val">-1.57</span>
                             </div>
                             <div class="slider-row">
                                 <label>J2</label>
-                                <input type="range" id="joint_1" min="-6.28" max="6.28" step="0.01" value="-2.0" oninput="updateJoints()">
-                                <span class="val-display" id="joint_1_val">-2.00</span>
+                                <input type="range" id="joint_1" min="-6.28" max="6.28" step="0.01" value="-1.5708" oninput="updateJoints()">
+                                <span class="val-display" id="joint_1_val">-1.57</span>
                             </div>
                             <div class="slider-row">
                                 <label>J3</label>
-                                <input type="range" id="joint_2" min="-3.14" max="3.14" step="0.01" value="2.0" oninput="updateJoints()">
-                                <span class="val-display" id="joint_2_val">2.00</span>
+                                <input type="range" id="joint_2" min="-3.14" max="3.14" step="0.01" value="1.5708" oninput="updateJoints()">
+                                <span class="val-display" id="joint_2_val">1.57</span>
                             </div>
                             <div class="slider-row">
                                 <label>J4</label>
-                                <input type="range" id="joint_3" min="-6.28" max="6.28" step="0.01" value="-1.57" oninput="updateJoints()">
+                                <input type="range" id="joint_3" min="-6.28" max="6.28" step="0.01" value="-1.5708" oninput="updateJoints()">
                                 <span class="val-display" id="joint_3_val">-1.57</span>
                             </div>
                             <div class="slider-row">
                                 <label>J5</label>
-                                <input type="range" id="joint_4" min="-6.28" max="6.28" step="0.01" value="-1.57" oninput="updateJoints()">
+                                <input type="range" id="joint_4" min="-6.28" max="6.28" step="0.01" value="-1.5708" oninput="updateJoints()">
                                 <span class="val-display" id="joint_4_val">-1.57</span>
                             </div>
                             <div class="slider-row">
@@ -894,6 +890,13 @@ def index():
                         clearInterval(reconnectTimer);
                         reconnectTimer = null;
                     }
+                    // Restore saved robot selection
+                    const savedRobot = localStorage.getItem('novasim_robot');
+                    if (savedRobot && savedRobot !== robotSelect.value) {
+                        robotSelect.value = savedRobot;
+                        send('switch_robot', {robot: savedRobot});
+                        updateRobotUI(savedRobot);
+                    }
                 };
 
                 ws.onclose = () => {
@@ -933,16 +936,32 @@ def index():
                                         euler[0].toFixed(2) + ', ' + euler[1].toFixed(2) + ', ' + euler[2].toFixed(2);
                                 }
 
-                                // Gripper: 0=closed, 255=open
+                                // Gripper: 0=open, 255=closed (Robotiq 2F-85)
                                 document.getElementById('gripper_val').innerText =
-                                    (data.gripper / 255 * 100).toFixed(0) + '% open';
+                                    ((255 - data.gripper) / 255 * 100).toFixed(0) + '% open';
                                 document.getElementById('arm_step_val').innerText = data.steps;
 
-                                // Update joint position display
+                                // Update joint position display and sync sliders
                                 if (data.joint_positions) {
                                     const jp = data.joint_positions;
                                     document.getElementById('joint_pos_display').innerText =
                                         jp.map(j => j.toFixed(2)).join(', ');
+                                    // Sync joint sliders with actual positions
+                                    for (let i = 0; i < 6; i++) {
+                                        document.getElementById('joint_' + i).value = jp[i];
+                                        document.getElementById('joint_' + i + '_val').innerText = jp[i].toFixed(2);
+                                    }
+                                }
+
+                                // Sync IK target sliders with actual EE position
+                                if (data.end_effector) {
+                                    const ee = data.end_effector;
+                                    document.getElementById('target_x').value = ee.x;
+                                    document.getElementById('target_x_val').innerText = ee.x.toFixed(2);
+                                    document.getElementById('target_y').value = ee.y;
+                                    document.getElementById('target_y_val').innerText = ee.y.toFixed(2);
+                                    document.getElementById('target_z').value = ee.z;
+                                    document.getElementById('target_z_val').innerText = ee.z.toFixed(2);
                                 }
 
                                 // Update control mode display
@@ -1036,21 +1055,22 @@ def index():
             function togglePanel() {
                 panelCollapsed = !panelCollapsed;
                 const content = document.getElementById('panel_content');
-                const btn = document.getElementById('collapse_btn');
+                const header = document.getElementById('panel_header');
                 const panel = document.getElementById('control_panel');
                 if (panelCollapsed) {
                     content.classList.add('collapsed');
                     panel.classList.add('collapsed');
-                    btn.innerText = '+';
+                    header.classList.add('collapsed');
                 } else {
                     content.classList.remove('collapsed');
                     panel.classList.remove('collapsed');
-                    btn.innerText = '-';
+                    header.classList.remove('collapsed');
                 }
             }
 
             function switchRobot() {
                 const robot = robotSelect.value;
+                localStorage.setItem('novasim_robot', robot);
                 send('switch_robot', {robot});
                 updateRobotUI(robot);
             }
@@ -1131,8 +1151,8 @@ def index():
             }
 
             function goToHome() {
-                // UR5 home position - reaching forward with gripper down
-                const home = [0.0, -2.0, 2.0, -1.57, -1.57, 0.0];
+                // UR5e home position - official MuJoCo Menagerie elbow-up pose
+                const home = [-1.5708, -1.5708, 1.5708, -1.5708, -1.5708, 0.0];
                 for (let i = 0; i < 6; i++) {
                     document.getElementById('joint_' + i).value = home[i];
                     document.getElementById('joint_' + i + '_val').innerText = home[i].toFixed(2);

robots/ur5/model/scene.xml

@@ -345,7 +345,8 @@
   </actuator>
 
   <keyframe>
-    <key name="home" qpos="0 -2.0 2.0 -1.5708 -1.5708 0 0 0 0 0 0 0 0 0 0.5 0.2 0.45 1 0 0 0"
-         ctrl="0 -2.0 2.0 -1.5708 -1.5708 0 128"/>
+    <!-- Official MuJoCo Menagerie UR5e home pose with gripper open (0=open) -->
+    <key name="home" qpos="-1.5708 -1.5708 1.5708 -1.5708 -1.5708 0 0 0 0 0 0 0 0 0 0.5 0.2 0.45 1 0 0 0"
+         ctrl="-1.5708 -1.5708 1.5708 -1.5708 -1.5708 0 0"/>
   </keyframe>
 </mujoco>

robots/ur5/ur5_env.py

@@ -32,14 +32,14 @@ class UR5Env(gym.Env):
         "wrist_3_joint",
     ]
 
-    # Home position - arm reaching forward with gripper pointing down
-    # This is a typical "ready to pick" pose for manipulation tasks
+    # Home position - official MuJoCo Menagerie UR5e configuration
+    # Classic "elbow up" manipulation pose from Universal Robots
     DEFAULT_HOME_POSE = np.array([
-        0.0,      # shoulder_pan - facing forward
-        -2.0,     # shoulder_lift - angled down
-        2.0,      # elbow - bent
-        -1.57,    # wrist_1 - aligned
-        -1.57,    # wrist_2 - gripper pointing down
+        -1.5708,  # shoulder_pan - rotated -90°
+        -1.5708,  # shoulder_lift - rotated -90°
+        1.5708,   # elbow - rotated +90°
+        -1.5708,  # wrist_1 - rotated -90°
+        -1.5708,  # wrist_2 - rotated -90°
         0.0,      # wrist_3 - no rotation
     ], dtype=np.float32)
 
@@ -117,8 +117,8 @@ class UR5Env(gym.Env):
         self._target_euler = np.array([0.0, np.pi/2, 0.0], dtype=np.float32)
         # Whether to use orientation in IK (user can toggle this)
         self._use_orientation = True
-        # Gripper target (0=closed, 255=open)
-        self._gripper_target = 128.0
+        # Gripper target: Robotiq 2F-85 uses 0=open, 255=closed
+        self._gripper_target = 0.0  # Start open
 
         # Control mode: 'ik' (end-effector target) or 'joint' (direct joint positions)
         self._control_mode = 'ik'
@@ -152,7 +152,7 @@ class UR5Env(gym.Env):
         return self._use_orientation
 
     def set_gripper(self, value: float):
-        """Set gripper target (0=closed, 255=open)."""
+        """Set gripper target. Robotiq 2F-85: 0=open, 255=closed."""
         self._gripper_target = np.clip(value, 0, 255)
 
     def get_gripper(self):
@@ -243,7 +243,7 @@ class UR5Env(gym.Env):
         # Set to home pose
         self.data.qpos[:6] = self.DEFAULT_HOME_POSE.copy()
         self.data.ctrl[:6] = self.DEFAULT_HOME_POSE.copy()
-        self.data.ctrl[6] = 128  # Gripper half open
+        self.data.ctrl[6] = 0  # Gripper open (Robotiq: 0=open, 255=closed)
 
         # Reset box position
         box_qpos_start = 6 + 8  # 6 arm joints + 8 gripper joints
@@ -254,7 +254,7 @@ class UR5Env(gym.Env):
         self._target_pos = np.array([0.4, 0.0, 0.4], dtype=np.float32)
         self._target_euler = np.array([0.0, np.pi/2, 0.0], dtype=np.float32)  # Gripper pointing down
         self.data.mocap_pos[0] = self._target_pos
-        self._gripper_target = 128.0
+        self._gripper_target = 0.0  # Open gripper
 
         mujoco.mj_forward(self.model, self.data)