A system operating based on Knudsen thermal force includes a microelectromechanical (MEMS) gas sensor, the MEMS gas sensor includes a substrate. The sensor further includes at least one stationary assembly fixedly coupled to the substrate, the at least one stationary assembly terminating at corresponding pads configured to receive an electrical current for heating the at least one stationary assembly. Additionally, the sensor includes at least one moveable assembly disposed above the substrate and biased to move substantially according to a main axis and juxtaposed with the at least one stationary assembly.