Introduction and preliminary evaluation of the Tongue Drive System: Wireless tongue-operated assistive technology for people with little or no upper-limb function

Abstract

Abstract-We have developed a wireless, noncontact, unobtrusive, tongue-operated assistive technology called the Tongue Drive System (TDS). The TDS provides people with minimal or no movement ability in their upper limbs with an efficacious tool for computer access and environmental control. A small permanent magnet secured on the tongue by implantation, piercing, or tissue adhesives is used as a tracer, the movement of which is detected by an array of magnetic field sensors mounted on a headset outside the mouth or on an orthodontic brace inside. The sensor output signals are wirelessly transmitted to an ultraportable computer carried on the user's clothing or wheelchair and are processed to extract the user's commands. The user can then use these commands to access a desktop computer, control a power wheelchair, or interact with his or her environment. To conduct human experiments, we developed on a face shield a prototype TDS with six direct commands and tested it on six nondisabled male subjects. Laboratory-based experimental results show that the TDS response time for >90% correctly completed commands is about 1 s, yielding an information transfer rate of ~120 bits/min.

Safety and Efficacy of Medically Performed Tongue Piercing in People with Tetraplegia for Use with Tongue-Operated Assistive Technology

“…10,11 The human tongue can move rapidly and accurately such that the tip can touch every tooth. [12][13][14][15] The direct connection between the brain and tongue generally remains intact even after high-level SCIs.…”

Tongue-controlled robotic rehabilitation: A feasibility study in people with stroke

“…A small magnet, the size of a lentil, was glued temporarily to the tip of the participant's tongue. Changes in the magnetic field caused by tongue movement were measured by the TDS magnetic sensors and wirelessly delivered to a computer to be translated into a pair of discrete commands (up and down) using our sensor-signal processing algorithms [24]. At the same time, the actual wrist angle was measured by a potentiometer embedded in the HM and reported to the computer.…”

“…The robot controller component, TDS (Figure 2), is a wireless and wearable technology that provides unobtrusive access to the physical volitional motion of the tongue [24][25][26][27]. It consists of a small magnetic tracer (Figure 2(a)) that is temporarily attached to the tongue via adhesive and a wireless headset that positions an array of magnetic sensors on both sides of the face near the cheeks (Figure 2(b)).…”

Tongue interface based on surface EMG signals of suprahyoid muscles

“…Some recent studies present solutions that consist of a small magnet or a piece of ferromagnetic material attached to the tongue tip via gluing or piercing, and a sensor array that detects the tongue tip position [9][10][11][12][13]. Sensor systems that include a small permanent magnet fixed to the tongue tip and an array of magnetic sensors have been presented in the literature [9][10][11].…”

“…Sensor systems that include a small permanent magnet fixed to the tongue tip and an array of magnetic sensors have been presented in the literature [9][10][11]. Some earlier reports introduced a tongue interface that includes an air-cored coil with inductance changed by a small ferromagnetic stud attached to the tongue [12,13].…”