Concetti Chiave
A practical framework for real-time multi-fingered grasping of unknown dynamic objects, leveraging a hybrid target model and adaptive grasp generation to handle challenging scenarios like conveyor belt and human-robot handover.
Sintesi
The proposed dynamic grasping framework consists of two asynchronous processes: Target Model Generation and Grasp Control.
Target Model Generation:
- Tracks the target object using a visual object tracker and constructs a point cloud model by fusing recent observations.
- Applies post-processing techniques like outlier removal and iterative closest point (ICP) alignment to maintain a robust and complete internal model of the target.
Grasp Control:
- Utilizes the latest internal model point cloud to generate a set of candidate grasps using the generative grasp synthesis model FFHNet.
- Selects the most suitable grasp based on a custom metric that considers both semantic (predicted grasp success) and geometric (pose difference) cues.
- Employs a visual servoing control law to guide the robot towards the target grasp pose, compensating for changes in the object's translation and rotation.
- Estimates the target's velocity using a Kalman filter and updates the grasp pose in case of missing visual feedback due to tracking loss or ICP failure.
- Executes the grasp when the current robot pose is predicted to result in a successful grasp.
The framework is evaluated in two realistic scenarios: grasping objects on a conveyor belt with varying speeds, and human-to-robot handovers. The results demonstrate the effectiveness and robustness of the proposed system, achieving high success rates for a variety of unknown objects in dynamic settings.
Statistiche
The conveyor belt experiment achieved an overall success rate of 71.7% across 120 grasp attempts on 10 different objects at speeds ranging from 0 to 220 mm/s.
The human-to-robot handover experiment achieved an overall success rate of 77% across 100 grasp attempts on the same 10 objects.
Citazioni
"To the best of our knowledge, we are the first to tackle this challenging problem of multi-fingered dynamic grasping for unknown objects and introduce a practical framework that can run efficiently on real hardware."
"Though easing the problem and enabling progress, it undermined the complexity of the real world. Aiming to relax these assumptions, we present a dynamic grasping framework for unknown objects in this work, which uses a five-fingered hand with visual servo control and can compensate for external disturbances."