The microrailgun: A new class of high velocity microactuator

Unlike linear current Lorentz force actuators, μ-railguns generate forces proportional to the square of current producing very high forces and velocities when driven by ultrafast capacitor discharges. μ-railguns were fabricated on an SOI wafer with 15 μm thick device layer. A test set-up was built for high speed capacitive discharge and synchronous stroboscopic imaging of device under actuation. Initial results demonstrate μ-railguns with actuation velocity of 45 m/s at resonant frequency of ~1 MHz, nearly 2 times higher than possible with PZT piezoelectrics.