Actions
Forum Thread Details
  • State Not Answered
  • Replies 15 replies
  • Subscribers 15 subscribers
  • Views 2264 views
  • Users 0 members are here
Related

Input Device for Disabled - Sense Mouth Open

Former Member

I am interested in building an input device that will provide a computer input for my daughter Liz who has Cerebral Palsy.

Liz has a great deal of involuntary head movement but she can reliably open and close her mouth to actuate a switch.

I would like to provide her with a wireless device that senses her mouth opening and closing to provide input to a single switch scanning communication system.  Years ago I combined a chin strap, a bennie cap and a micro switch to provide that function.  I am looking for ideas!

I have searched many sites looking for devices but all require her head to be held fixed which is impossible for Liz.

  • 0 in reply to YT2095

    The Kinect approach would utilize facial recognition which I tried 18 years ago.  I built a system using a video camera, frame grabber, image processing with eigenface algo.  It worked if Liz's head was completely still.  Today she can not tolerate her head immobilized.  A second problem is the ambient lighting and getting a frontal image.  The state of the act has certainly improved with huge increases in processing power but the algos are still lacking in reliability.  RFID is a good way to go. No power.  Interrogate the  sensor(s).  Another possibility is to energy harvest from the surrounding area to provide power for the circuits.  Having the sensor directly on her face is the best data collecting site.  The epidermal electronic patch needs to be completely integrated containing either a power source and transmitter or passive RFID type. 

  • 0 in reply to Catwell

    Cabe,

    Good to hear from you.  Zigbee looks good for a protocol or possibly IEEE 802.15.4.  RFID is a good way to go. No power.  Interrogate the  sensor(s).  Another possibility is to energy harvest from the surrounding area to provide power for the circuits.  Having the sensor directly on her face is the best data collecting site.  The epidermal electronic patch needs to be completely integrated containing either a power source and transmitter or passive RFID type.  They are getting close to a prototype with more integration.  The patch is non invasive, extremely thin, can measure strain, temp and area potentials.  The current prototypes need power.  They are just raw analog signal circuits.  Connecting wires to the patch is lab work.  Finding a micro sized package that could be placed on her cheek, attached to the patch circuit is not something I am finding.  I would take apart, just to test the patch circuit, a micro miniature, wireless sensor of almost any type just to get the back end processing.  Or if I could find a RFID package, again micro miniature that could be wired to the patch and the whole thing covered with some 3M Tagaderm.  Its a tall order but the other option is to wait a while longer until the EE patch gets more integrated.

    John

  • 0 in reply to RWM

    I am trying to sense directly on Liz's body.  Camera not as good.

  • 0 in reply to Former Member

    John,

     

    Aside from being great for mobile identification, RFID for a power source from sensors and microcontrollers (uC) is still on the fringe of research. If you can break that field, by all means.

     

    If you are having issues, then external battery power may be the only solution.

    Place the battery into the patchwork. With low power components, you might be able to do a lot.

     

    Many of the links I would like to show you are down on element14. What I would show is just examples of how doing what you propose is possible using standard materials and tech.

    A recent development might not show jaw movement, but it can accomplish everything else you want. See the pajama that is a complete baby monitoring system. This could be attached to the body and give you all the data you mentioned.

     

    However, only sensing jaw movement will make the patch simple.

     

    Something has to sense particular jaw muscle signal firing. From here data could be sent via wires to a body harness, like the pajama system above. You would have the best of all worlds, an off-the-shelf monitoring system with your cheek patch communication system.

     

    To go wireless, you will have to integrate a transmitter and battery system in the patch. Finding an off-the-shelf  product to do all this is going to be impossible. I suggest we start by finding the lowest power transmitter possible and a small form factor uC to pair with it.

     

    Cabe

  • 0

    John,

     

    It was just a matter of time. It looks like Georgia Tech has created the device you need. It is a magnetic sensor interface that uses the tongue and a retainer. Perhaps you can get in on the trials, or just stay informed on the project's progress.

     

    Contact professor Maysam Ghovanloo at Georgia Tech.

     

    Cabe

    http://twitter.com/Cabe_e14