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The ideal microrobots are millimeter sized with integrated actuators, power sources, sensors, and controllers. Many researchers take the inspiration from insects for the mechanical or electrical designs to construct small sized robotic systems. Previously, the authors proposed and demonstrated microrobots which can replicate the tripod gait locomotion of an ant and the legs were actuated by shape memory alloy actuators. Shape memory alloy provided a large deformation and a large force, but the power consumption was as high as 94 mW to actuate a single leg. This paper discusses the silicon electrostatic inchworm motor chip with low energy consumption for the robot leg by using a small-size power source. The inchworm motor chip has actuated by electrostatic motors. The power consumption is low as 1.0 mW compering with shape memory alloy actuators. The reciprocal motion of the inchworm motor chip is power by the silicon photovoltaic cells. Results show the 7.5 mm square size photovoltaic cells could produce 60 V to actuate the inchworm motor chip. The generated force is enough to move the leg of the microrobot. We have shown actuation of the microrobot leg using an electrostatic inchworm motor chip. This result is the first instance of an electrostatic motor driving an off-chip structure.

We demonstrate high-force-density rapid actuation of electrostatic gap-closing actuator (GCA) arrays operating in an aqueous environment. These devices are designed to generate up to 4.6 mN at 6 V drive signal amplitudes and have measured pull-in times as fast as 121 μs with no electrolysis. We present a new model for the dynamics of aqueous GCA operation which includes the inertia of the squeezed fluid and proximity of the substrate to the device layer. The actuators operate in deionized water, and preliminary tests demonstrate actuation in ionic solutions (10 mM) and partial operation of submerged inchworm motors based on GCA arrays.

This work presents the locomotion of a ground-based single-legged silicon robot. The robot measures 5mm × 6mm × 0.5mm and weighs 18mg. Fabricated in a silicon-on-insulator (SOI) process, the robot is based on electrostatic inchworm motors that drive a 2 degree-of-freedom (DOF) planar silicon linkage that acts as the leg. The leg sweeps out an area of approximately 500μm × 500μm off the edge of the chip. The chip is connected to power and control by long flexible wires which also act to support the robot upright. The robot exerts over 1.5× its weight in the vertical axis, enough to lift its body and push itself forward.

We describe KAPAO, our project to develop and deploy a low-cost, remote-access, natural guide star adaptive optics (AO) system for the Pomona College Table Mountain Observatory (TMO) 1-meter telescope. We use a commercially available 140-actuator BMC MEMS deformable mirror and a version of the Robo-AO control software developed by Caltech and IUCAA. We have structured our development around the rapid building and testing of a prototype system, KAPAO-Alpha, while simultaneously designing our more capable final system, KAPAO-Prime. The main differences between these systems are the prototype's reliance on off-the-shelf optics and a single visible-light science camera versus the final design's improved throughput and capabilities due to the use of custom optics and dual-band, visible and near-infrared imaging. In this paper, we present the instrument design and on-sky closed-loop testing of KAPAO-Alpha as well as our plans for KAPAO-Prime. The primarily undergraduate-education nature of our partner institutions, both public (Sonoma State University) and private (Pomona and Harvey Mudd Colleges), has enabled us to engage physics, astronomy, and engineering undergraduates in all phases of this project. This material is based upon work supported by the National Science Foundation under Grant No. 0960343., 10 pages and 11 figures