Source note

DAM-VLA: Decoupled Asynchronous Multimodal Vision Language Action model

Vision Language ActionRobot Foundation ModelAsynchronous ControlMultimodal SensingForce Torque

DAM-VLA claims that VLA policies work better when vision, language, force, and proprioception update at their own rates. It reports 95.2% average success on seven real robot manipulation tasks while running smooth 100 Hz control.

  • Standard VLA models process all inputs on one clock, which wastes compute on slow signals like language and vision and misses fast contact signals like force and torque.
  • This matters for contact-rich manipulation because force spikes can happen at 100 to 500 Hz, while RGB frames carry useful changes closer to 3 to 10 Hz.
  • Synchronous action generation waits for a full observation bundle, which adds latency and limits reactive control.
  • DAM-VLA keeps a latent buffer for each modality. Language is encoded once, vision updates sparsely, and force plus proprioception update at the control rate.
  • The action head reads all buffers at every control step, so action output can continue even when slow modalities have no new input.
  • Vision uses a short-term memory buffer: 16 visual frames at 25 Hz, about 0.64 seconds of context.
  • Force and proprioception use dense histories: 96 samples at 100 Hz, about 0.96 seconds of contact and state context.
  • New modality information enters the X-VLA action expert through gated cross-attention modules, which leave the pretrained self-attention weights unchanged.
  • On seven real Franka manipulation tasks with 15 trials per task, DAM-VLA reaches 95.2% average success versus 40.95% for X-VLA_25, the strongest synchronous baseline. That is a +54.25 percentage point gain and about 2.32x higher success.
  • Naive high-frequency synchronous X-VLA_100 drops to 21.9% average success, below X-VLA_25 at 40.95%, showing that upsampling visual frames to 100 Hz hurts performance in this setup.
  • DAM-VLA succeeds on tasks where X-VLA_25 fails or nearly fails: Handwash 100.0% vs 0.0%, Lego 93.3% vs 0.0%, Socket 80.0% vs 6.7%, and Button 93.3% vs 13.3%.
  • The strongest concatenation baseline, X-VLA_AFM, uses force and memory but reaches 54.3% average success, far below DAM-VLA at 95.2%.
  • Ablations show additive gains: async alone 40.0%, async plus visual memory 58.1%, async plus force 66.7%, and full DAM-VLA 95.2%.
  • The reported controller runs at 100 Hz. Replanning rates are about 1 Hz for X-VLA_25, 3.5 Hz for X-VLA_100, and 5.5 Hz for DAM-VLA with s=22; a 200 Hz controller test reports about 8 to 17 Hz replanning depending on s.