Design Criteria: Tongue and Device Accuracy

    • Given the range of motion and accuracy provided by the tongue, the roof of the mouth provides a stable surface for the insertion of a wireless inductive tongue-computer interface (ITCI) for input. An “activation unit” composed of biocompatible stainless steel is placed on the tip of the tongue (Caltenco et al., 2014) for a precise selection of sensors.
      • The interface resting on the roof of the mouth consists of sensor boards with multiple coils that detect when a ferromagnetic material ( the activation unit ) is placed nearby. 
      • Implementing the activation and palette together, text input, and pointing direction (scrolling) is possible for patients using online media. 
      • The sensors process and filter information through a fuzzy inference system (FIS), which determines the speed and direction of inputs (Caltenco et al., 2013). To deduce any further false sensor inputs, the device is calibrated before use to set the standard type of movement for the dynamics between tongue and device. 
    • Skill improvement is possible and advised for the most effective use of the device through training sessions consisting of games that demand mouse-pointer control (Caltenco et al., 2014). Games can include versions of Whack-a-mole for key selection practice, Tetris for tongue mousepad (TMP) navigation, and more.
    • To increase pointer-to-sensor accuracy, visual feedback for the user is preferable to trace the movement of the activation unit on the TMP. In turn, a subsequent study showed a spike of 15 to 23 characters per minute after visual aid was provided (Caltenco et al., 2013).
    • Software including TongueWise and a program running in Matlab R2008a compute the main work in distinguishing between intentional and unintentional movements for accurate representation of the user’s input. 

Design Criteria: Comfortable for the User & Biocompatible

    • Biocompatibility of the Biomaterial:
      • Should not cause further health complications
      • Needs to be able to withstand corrosion and overtime usage.
      • Maintain functionality in wet environment.
    • The “retainers” can be customized to the patient for extra comfort.
      • TR material made from PETG copolymer by Bay Dental Direct will be used for the retainters (Gardner et al., 2003).
    • To decrease possible tongue fatigue, the flat board keyboard will separated and shifted to the back of each individual front teeth (Caltenco et al., 2013). 
    • The flat-tongue mousepad (TMP) will be moved forward towards the front teeth. This will allow the tongue to focus it’s movements in one area (Caltenco et al., 2013).
    • The Histoacryl® soft tissue glue will be replaced with a dual oral tissue adhesive that is capable of wet adhesion and can adhere to soft and hard tissues (Boda et al., 2020).