Dynamic obstacle avoidance for manipulators using distance calculation and discrete detection

- A novel method based on distance calculation and discrete detection is proposed for avoiding dynamic obstacle timely and accurately aiming at redundant manipulators.
- The arbitrarily-shaped dynamic obstacles obtained from Kinect-V2 camera in real-time are converted into their convex hulls for calculating distances.
- An improved discrete collision detection is presented that can adjust detection step-size adaptively for accuracy and efficiency.

In order to avoid dynamic obstacle timely during manufacturing tasks performed by manipulators, a novel method based on distance calculation and discrete detection is proposed. The nearest distances between the links of a manipulator and the convex hull of an arbitrarily-shaped dynamic obstacle obtained from Kinect-V2 camera in real-time are calculated by Gilbert-Johnson-Keerthi algorithm, and the minimum one is defined as the closest distance between the manipulator and the obstacle. When the closest distance is less than a safe value, whether the dynamic obstacle is located in the global path of the manipulator is determined by improved discrete collision detection, which can adjust detection step-size adaptively for accuracy and efficiency. If the obstacle will collide with the manipulator, set a local goal and re-plan a local path for the manipulator. The proposed method is implemented in Robot Operating System (ROS) using C++. The experiments indicate that the proposed method can perform safe and timely dynamic avoidance for redundant manipulators in human-robot interaction.