Power and Control Electronics

Once the structure and actuators have been built and incoporated together, we need a way to power and control the actuators.  The power supply is obtained via batteries, but the 3.7V supplied by them is hardly adequate for the high voltages required by the PZT cantilever actuators.   The fact that we need to significantly step up the voltage as well as some method for adequately controling the actuators requires us to have some type of on board processing.  A populated board that we have developed to accomplish this is shown below.

power and control electronics board

Developed for an autonomous 2g glider, we have also sucessfully adapted it for use in a 3g crawling robot.  It provides approximately 200 VDC using a custom charge pump cascaded after a commercial boost converter, and has a 1 Mips processor onboard. The board is programmable via IR light (using a finite state machine (FSM) method), and has many other possible sensing features that can be added on, such as light seeking or optical flow sensing. The board itself is made out of 2µm polyimide flex circuit, and populated weighs approximately 440 mg.  More details about this board can be found in the paper reference given below.

Paper reference:
Design, Fabrication and Initial Results of a 2g Autonomous Glider
R.J. Wood, S. Avadhanula, E. Steltz, M. Seeman, J. Entwistle, A. Bachrach, G. Barrows, S. Sanders, and R.S. Fearing,
31st Annual Conference, IEEE Industrial Electronics Society 2005 Meeting, Raleigh North Carolina, Nov. 6-10, 2005.