title: A mm-sized wirelessly powered and remotely controlled locomotive implant.
abstract: A wirelessly powered and controlled implantable device capable of locomotion in a fluid medium is presented. Two scalable low-power propulsion methods are described that achieve roughly an order of magnitude better performance than existing methods in terms of thrust conversion efficiency. The wireless prototype occupies 0.6 mm × 1 mm in 65 nm CMOS with an external 2 mm × 2 mm receive antenna. The IC consists of a matching network, a rectifier, a bandgap reference, a regulator, a demodulator, a digital controller, and high-current drivers that interface directly with the propulsion system. It receives 500 μW from a 2 W 1.86 GHz power signal at a distance of 5 cm. Asynchronous pulse-width modulation on the carrier allows for data rates from 2.5-25 Mbps with energy efficiency of 0.5 pJ/b at 10 Mbps. The received data configures the propulsion system drivers, which are capable of driving up to 2 mA at 0.2 V and can achieve speed of 0.53 cm/sec in a 0.06 T magnetic field.
authors.affiliation: Electrical Engineering Department, Stanford University, Stanford,CA 94305, USA. pivonka@stanford.edu
authors.forename: Daniel
authors.initials: D
authors.lastname: Pivonka
authors.forename: Anatoly
authors.initials: A
authors.lastname: Yakovlev
authors.forename: Ada S Y
authors.initials: AS
authors.lastname: Poon
authors.forename: Teresa
authors.initials: T
authors.lastname: Meng
mesh_terms: D001698:Biomedical Engineering / Q000295:instrumentation; D016503:Drug Delivery Systems / Q000295:instrumentation; D011211:Electric Power Supplies; D004867:Equipment Design; D006801:Humans; D057446:Hydrodynamics; D060328:Magnetic Phenomena; D009038:Motion; D019736:Prostheses and Implants; D013686:Telemetry / Q000295:instrumentation; D059015:Wireless Technology