Efficient and Collision-Free Human–Robot Collaboration Based on Intention and Trajectory Prediction

Human–robot collaboration (HRC) is an important topic for manufacturing and household robotics. It is very challenging to ensure both efficiency and safety in HRC. This article presents an HRC pipeline that generates efficient and collision-free robot trajectories based on predictions of the human arm and hand (AH) motions. We train a recurrent neural network for AH trajectory prediction based on observed initial trajectory segments. To increase the accuracy of target estimation at an early stage, the observed and the predicted hand palm trajectories are combined to predict the current AH motion target using Gaussian mixture models (GMMs). An optimization-based trajectory generation algorithm is proposed to ensure the safety of the human while collaborating with the robot. The proposed system is validated in a shared-workspace scenario with human pick-and-place motions. The task can be safely and efficiently completed. The results demonstrate that our proposed pipeline can predict the human AH trajectory and estimate the motion target intended by the human accurately and early.