mujoco.Renderer(model, width=640, height=640) is asking for an image size larger than what the MuJoCo model framebuffer allows by default.

tray_sim.py

@@ -29,9 +29,9 @@ def run_tray_simulation(seed=0, num_objects=N_OBJECTS):
     pusher_vel_idx = num_objects * 6
 
     # Renderer
-    renderer = mujoco.Renderer(model, width=640, height=640)
-    frames = []
+    renderer = mujoco.Renderer(model, width=480, height=480)
 
+    frames = []
     keyframes = {0: None, 25: None, 50: None, 200: None}
 
     for t in range(SIM_STEPS):
@@ -39,12 +39,13 @@ def run_tray_simulation(seed=0, num_objects=N_OBJECTS):
             # Activate pusher
             data.qvel[pusher_vel_idx:pusher_vel_idx+3] = [-0.05, 0.05, 0.0]  # toward center
 
-        if t in keyframes:
-            imageio.imwrite(f"/tmp/frame_{t}.png", img)
-
         mujoco.mj_step(model, data)
         renderer.update_scene(data)
         img = renderer.render()
+
+        if t in keyframes:
+            imageio.imwrite(f"/tmp/frame_{t}.png", img)
+
         frames.append(img)
 
     renderer.close()