Assembly manipulation of small objects by dual-arm manipulator

Purpose - The purpose of this paper is to propose an assembly robot that exhibits specific human-like skills, with minimal structural cost and a number of external sensors.Design methodology approach - The authors have employed vision processing using multiple cameras to determine targets and postures and propose strategies to determine the pose of a target and to prevent collisions between the fingers and obstacles in an environment with mixed objects. Furthermore, a dynamic trajectory planner integrates the vision and force sensors of the robot hand for the assigned task.Findings - The authors obtained satisfactory experimental results for autonomous real-time grasping and screwing. The results verified the capability of the robot for handling small objects.Research limitations implications - More effective robotic manipulation requires a higher degree of target orientation data, which will be a future study of this research.Practical implications - Practicality has been established through results, indicating the capability of the robot to implement human-like skilled manipulation of small objects. This can potentially reduce the high labor cost associated with the small-scale manufacture of custom-made products.Originality value - Screwing of nuts of minimum M2 size (diameter, 4.6 mm) and M8-M10 bolts (head diameter, 15-19.6 mm; length, 50-80 mm) by cooperating two seven-link arm manipulators and three-fingered hands shows the robot's capability to manipulate small objects.