Magnetic Field-Priority Force Control for Automated Manipulation in Large Workspaces With Reconfigurable Electromagnetic Actuation System

Rapid technological advancements in remote-controlled magnetic robots that operate inside the human body have strongly stimulated the development of magnetic actuation systems owing to their ability to produce demanding magnetic fields and forces. However, the efficient generation of the combined field and force in large workspaces still needs to be improved. To resolve this critical challenge, we first investigated the required number of mobile magnetic sources for a magnetic actuation system to regulate field and force in large workspaces. Subsequently, we demonstrated that a three-electromagnetic-coil configuration can effectively produce the desired field and force. This is achieved through the implementation of a field-priority force control method utilizing three robotic arms. Notably, this method considers Yoshikawa manipulability for each robotic arm, which matters for manipulating magnetic robots in large workspaces. Specifically, we evaluated the force error by sampling 50 different field-force combinations from the workspace. Finally, a reconfigurable electromagnetic actuation system (REMA) was developed by mounting three mobile electromagnetic coils mounted on three independent robotic arms. The effectiveness of the proposed method and platform was demonstrated by actuating a capsule robot in both 2-D and 3-D application scenarios.