title: A wireless magnetoresistive sensing system for an intraoral tongue-computer interface.
abstract: Tongue drive system (TDS) is a tongue-operated, minimally invasive, unobtrusive, and wireless assistive technology (AT) that infers users' intentions by detecting their voluntary tongue motion and translating them into user-defined commands. Here we present the new intraoral version of the TDS (iTDS), which has been implemented in the form of a dental retainer. The iTDS system-on-a-chip (SoC) features a configurable analog front-end (AFE) that reads the magnetic field variations inside the mouth from four 3-axial magnetoresistive sensors located at four corners of the iTDS printed circuit board (PCB). A dual-band transmitter (Tx) on the same chip operates at 27 and 432 MHz in the Industrial/Scientific/Medical (ISM) band to allow users to switch in the presence of external interference. The Tx streams the digitized samples to a custom-designed TDS universal interface, built from commercial off-the-shelf (COTS) components, which delivers the iTDS data to other devices such as smartphones, personal computers (PC), and powered wheelchairs (PWC). Another key block on the iTDS SoC is the power management integrated circuit (PMIC), which provides individually regulated and duty-cycled 1.8 V supplies for sensors, AFE, Tx, and digital control blocks. The PMIC also charges a 50 mAh Li-ion battery with constant current up to 4.2 V, and recovers data and clock to update its configuration register through a 13.56 MHz inductive link. The iTDS SoC has been implemented in a 0.5-μm standard CMOS process and consumes 3.7 mW on average.
authors.affiliation: GT-Bionics Lab, School of Electrical and Computer Engineering, GeorgiaInstitute of Technology, Atlanta, GA 30332-0250, USA.
authors.forename: Hangue
authors.initials: H
authors.lastname: Park
authors.forename: Mehdi
authors.initials: M
authors.lastname: Kiani
authors.forename: Hyung-Min
authors.initials: HM
authors.lastname: Lee
authors.forename: Jeonghee
authors.initials: J
authors.lastname: Kim
authors.forename: Jacob
authors.initials: J
authors.lastname: Block
authors.forename: Benoit
authors.initials: B
authors.lastname: Gosselin
authors.forename: Maysam
authors.initials: M
authors.lastname: Ghovanloo
mesh_terms: D001698:Biomedical Engineering / Q000295:instrumentation; D004867:Equipment Design; D006801:Humans; D060328:Magnetic Phenomena; D012656:Self-Help Devices; D013119:Spinal Cord Injuries / Q000503:physiopathology / Q000534:rehabilitation; D013686:Telemetry / Q000295:instrumentation; D014059:Tongue / Q000502:physiology*; D014584:User-Computer Interface; D059015:Wireless Technology / Q000295:instrumentation