Magnetically Actuated Floating Millirobot Platform for Streamlined Flexible Neural Electrode Manipulation

Flexible neural electrodes have received increasing interests for implantable brain computer interfaces. However, due to the flexibility and miniaturization requirements, these fine neural electrodes often require a rigid probe as the shuttle to assist the successful implantation. Hence, the primary prerequisites for electrode implantation is the successful micro-assembly of the rigid probe and the electrode with a tiny engaging hole, whereas the conventional manual manipulation is error prone and time consuming. Although there have been recent development in micro-manipulation systems, a specific micro-manipulation system tailored for high-throughput, streamlined manipulations of multiple flexible electrodes is still lacking.. Therefore, this paper proposes a micro-manipulation system of streamlined floating robot for flexible electrode manipulation. The electrodes are deployed on a well-designed Magnetically-actuated Milli-Eelectrode Boat (MMEB), which can be magnetically controlled by a circular rotating magnet. A deep-learning based StreamNet is developed for visual servoing of the MMEB is achieved by accurately detecting the engaging hole from a microscopic vision system. In addition, the Linear Active Disturbance Rejection Control (LADRC) is used to ensure stable and precise movement of the MMEB on the water surface. Experiments using phantom electrodes were conducted to evaluate the micro-manipulation process. The results show that the proposed system can achieve accurate locomotion of the engaging hole during both loading and releasing processes, with an average steady-state error is less than 3%.