Here, the simultaneous actuation of multiple microrobots with different speeds demonstrates a capability of the microrobot control system: parallel, uncoupled movement of microrobots along trajectories that vary in direction and distance traveled during the same actuation time.
In addition, micromanipulation using the simultaneous actuation of multiple microrobots requires a robust control system to enable independent motion.
This experiment demonstrates that multiple microrobots adjacent to a micro-object do not interfere with the manipulation of the object.
Moreover, the OFB microrobot system, which is capable of the independent actuation of many microrobots, utilizes vision-based automatic actuation for the simultaneous participation of multiple microrobots in micromanipulation, as it is difficult for a human operator to control many microrobots.
The hybrid control system described above was used to perform closed-loop actuation of a single microrobot, grasp planning of multiple microrobots for a micromanipulation task, closed-loop actuation of multiple microrobots, and open-loop micromanipulation of a star-shaped SU-8 microstructure.
This closed-loop actuation allows automatic and simultaneous actuation of multiple microrobots for micromanipulation with precise positioning, beyond the capacity of a human operator.
In addition to increasing the throughput of microassembly tasks, multiple microrobots can enable certain manipulation tasks, such as studying temporal dynamics of micro-object interactions.
Bacteria-propelled microrobots based on the motility of the bacteria have a limited degree of controllability [27], but the use of electrical signals [28], UV light [4], or chemical energy [3, 27] in conjunction with bacteria propulsion helps to achieve higher controllability, and has been used to actuate multiple microrobots [3].
This paper demonstrates a hybrid closed-loop vision-assisted control system capable of actuating multiple microrobots simultaneously and positioning them at precise locations relative to micro-objects under manipulation.
In this case, it may be necessary to have several objects moving at various velocities and trajectories relative to one another, which can be achieved by using multiple microrobots.
