This project focuses on developing a new generation of sub-centimeter MEMS-based walking robots. These robots are based on electrostatic actuators driving planar silicon linkages, all fabricated in the device layer of a silicon-on-insulator (SOI) wafer. By using electrostatic actuation, these legs have the advantage of being low power compared to other microrobot leg designs. This is key to granting the robot autonomy through low-power energy harvesting. The ultimate goal will be to join these silicon legs with a CMOS brain, battery power, a high voltage power source, and high voltage buffers to achieve a fully autonomous walking microrobot. After demonstrating locomotion of a single-legged walking robot through tethered external power, we developed a first generation silicon hexapod based on multi-chip assembly and showed it take its first steps. We have also demonstrated electrostatic inchworm motors capable of actuating a shuttle at 0.4m/s. We are now developing a next generation quadruped walking robot that uses zero insertion force MEMS socket designs for assembly. To build this quadruped robot, we are developing a seven SOI fabrication process that would allow for an optimized robotic leg design.