We are developing novel methods for the control of microrobots, which are under 1 mm in size. The small size of these microrobots could enable them to have potential applications in healthcare, microfluidics or micro-scale factories. Our work focuses on addressing the challenges in microrobot motion and the manipulation of objects at the micro-scale in confined spaces. Microrobot actuation is accomplished by computer-controlled magnetic fields, supplied by a set of magnetic coils or permanent magnets. Our research is into methods of creating strong controllable fields using magnetic coils or permanent magnet arrays, and in using those fields to drive mobile micro-robot devices in 2D or 3D environments.
Millimetre-Scale Soft-Bodied Magnetic Devices
Inspired by the movement of cilia, we are developing a novel type of soft-bodied magnetic micro-robots which using the undulation of their bodies for propulsion. The swimmer’s body changes continuously in a rotating uniform magnetic field, inducing a traveling wave which mimics the natural motion of some swimming micro-organisms. Magnetic fields are used to control the swimmer’s position, heading, and speed.
Taking advantage of the difference between their internal magnetization profiles, two swimmers can be controlled independently to arrive at different positions using one single global magnetic field. We are developing controllers to move these small swimmer teams for applications in microfluidics, medicine and basic research in the motion of micro-organisms.
One significant challenge in micro-robotics is the simultaneous control of multiple untethered agents. This is difficult with current micro-robotic systems because driving signals are typically uniform in the workspace, so all agents receive identical control inputs. Methods to address individual microrobots must be developed for the full control of multiple micro-robots
Research on magnetic micro-agents is limited in how close the agents can operate to one another. When they do operate close together, the magnetic agents abruptly stick together leading to control instability. We are developing methods for the stable motion control of two identical magnetic microrobot agents operating in close proximity based on the local radial and transverse magnetic forces appearing between these agents. By controlling the inter-agent magnetic forces through controlled rotation of the agents, we are showing that it is possible to maintain a desired spacing between nearby agents at distances as small as 3 agent’s radius under visual feedback control. We plan to use such controllers for applications where multiple magnetic micro-robots can work in close proximity on teamwork manipulation tasks.
Canadian Institutes of Health Research (CIHR):
University of Toronto Medicine by Design:
Ontario Ministry of Research and Innovation: