A voice coil based vibration platform for micro robots application
In micro-scale robot dynamics studies, there are still many challenges from their wide
bandwidth, fast response, and high energy density properties. Among them, it is especially important to find a proper power source, and the piezoelectric actuator is the most popular solution. However, due to its intrinsic stiffness and friction, it brings complexity to the robot system. Since it is unnecessary for this kind of actuators to build an accurate model, we developed another power solution to substitute the traditional piezoelectric actuator. In this research, we fabricated and tested an experimental platform based on voice coil, which generates sinusoidal vibrations. We fixed a carbon fiber rod to a subwoofer with external constraints, including a Sarrus linkage. The Sarrus linkage was designed and built
viiiusing the SCM (Smart Composite Microstructures) method. With no feedback attended, the open loop system was proved to be able to generate accurate sinusoidal wave across 10-150 Hz. Integrated with a PI controller, the vibration platform was tested by giving a 1mm peak-to-peak amplitude output wave goal. Both the control voltage and output displacement were stable with smooth and fast transitions. To test the capacity, another loaded test has been done by attaching a compliant micro wing to the vibration platform. There is no significant difference between output displacements from loaded and no-load system, and all amplitude errors are smaller than 0.05mm. It is verified that this vibration platform is able to generate robust, accurate, and reliable sinusoidal wave at micro robot scale.