The continuing thrust toward greater miniaturization and integration of microrobotics and microelectronics has resulted in significant work toward the development of piezoelectric actuators. One of the bottlenecks of the piezo-actuator is its necessity of the electric lead wire, which is too heavy for a miniaturized self-propelling robot less than 1 cm3. The important reason is a drastic reduction of the propelling friction force due to the increase in specific area; that is, surface area/volume or weight ratio. “What if you, an expert on actuators, could produce a remote-controlled actuator that would bypass the electrical lead?" To many people, “remote control” equals control by radio waves, light waves, or sound. Light-controlled actuators require that light energy be transduced twice: first from light energy to electrical energy, and second from electrical energy to mechanical energy. These are “photovoltaic” and “piezoelectric” effects. A solar cell is a wellknown photovoltaic device, but it does not generate sufficient voltage to drive a piezoelectric device; in other words, this combination fails due to the electric impedance mismatch. The key to success is to adopt a high-impedance photovoltaic effect (so-called anomalous or bulk photovoltaic effect in piezoelectrics), which is totally different from the p-n junction-based solar cell.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)