Wireless control of powered wheelchairs with tongue motion using tongue drive assistive technology.
ABSTRACT Tongue Drive system (TDS) is a tongue-operated unobtrusive wireless assistive technology, which can potentially provide people with severe disabilities with effective computer access and environment control. It translates users' intentions into control commands by detecting and classifying their voluntary tongue motion utilizing a small permanent magnet, secured on the tongue, and an array of magnetic sensors mounted on a headset outside the mouth or an orthodontic brace inside. We have developed customized interface circuitry and implemented four control strategies to drive a powered wheelchair (PWC) using an external TDS prototype. The system has been evaluated by five able-bodied human subjects. The results showed that all subjects could easily operate the PWC using their tongue movements, and different control strategies worked better depending on the users' familiarity with the TDS.
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ABSTRACT: The primary aim of this study was to investigate the effect of different training types and secondary to test gender differences on the training-related cortical plasticity induced by three different tongue training paradigms: 1. Therapeutic tongue exercises (TTE), 2. Playing computer games with the tongue using Tongue Drive System (TDS) and 3. Tongue-protrusion task (TPT). Forty-eight participants were randomized into 3 groups with 1 h of TTE, TDS, or TPT. Stimulus-response curves of motor evoked potentials (MEPs) and motor cortex mapping for tongue muscles and first dorsal interosseous (FDI) (control) were established using transcranial magnetic stimulation (TMS) at three time-points: (1) before tongue training, (2) immediately after training, (3) 1 h after training. Subject-based reports of motivation, fun, pain and fatigue were evaluated on 0-10 numerical rating scales (NRS) after training. The resting motor thresholds of tongue MEPs were lowered by training with TDS and TPT (P<0.011) but not by TTE (P=0.167). Tongue MEP amplitudes increased after training with TDS and TPT (P<0.030) but not with TTE (P=0.302). Men had higher MEPs than women in the TDS group (P<0.045) at all time-points. No significant effect of tongue training on FDI MEPs was observed (P>0.335). The tongue cortical motor map areas were not significantly increased by training (P>0.142). Training with TDS was most motivating and fun (P<0.001) and TTE was rated most painful (P<0.001). Fatigue level was not different between groups (P>0.071). These findings suggest a differential effect of tongue training paradigms on training-induced cortical plasticity and subject-based scores of fun, motivation and pain in healthy participants.Neuroscience 04/2013; · 3.12 Impact Factor
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ABSTRACT: One of the most important problems for patients with severe disability is the control systems for electric wheelchairs, because they cannot use common systems as the joystick or keypads. This paper proposes the development of a magnetic control system (MCS) to handle a power wheelchair as an alternative control system for patients with spinal cord injuries, as quadriplegics. The proposed system uses the movements of the patient's tongue to operate the power wheelchair, and also includes the development of new communication protocols for the wheelchair through a microcontroller, bridge H and magnetic control.Electronics, Communications and Computing (CONIELECOMP), 2013 International Conference on; 01/2013