Joe Barnick

Age: 40

Disability: Spinal Muscular Atrophy (Type II)

Device: 27-inch iMac, 15-inch MacBook Pro, HP Laptop

Platform: macOS 10.13 High Sierra, Mac OS X 10.9 Mavericks, Windows 10

Software: macOS Accessibility Keyboard, Windows 10 On-screen Keyboard, KeyStrokes by AssistiveWare

Hardware: TetraMouse XA by TetraLite Products, Micro Light Switch by AbleNet, Switch Adapted Logitech Trackman Marble Wheel Trackball, Baby Bottle Holder by Mothers 3rd Arm, Wheelchair Tray, Sunmate Foam Pads, SteelSeries QcK Gaming Mouse Pad, rubber shelf liner

Extremely limited movement in my thumbs, movement in my bottom lip/chin

To access my computers, I use a TetraMouse XA ( from TetraLite Products to control the cursor and a Micro Light Switch ( from AbleNet to left-click.

I move the right joystick on the TetraMouse XA with my bottom lip/chin to control the cursor. The TetraMouse XA offers full proportional cursor control and I am able to move the cursor 360 degrees.

The Micro Light Switch is plugged into a switch adapted Logitech Trackman Marble Wheel Trackball that was adapted by my local Center for Disability Services. The trackball is adapted with 1/8-in/3.5-mm mono jacks for left-click, middle-click, and right-click so that adaptive switches can be plugged into these jacks and these click functions can be performed.

Both the TetraMouse XA and the Logitech Trackman Marble Wheel Trackball are connected to my computer via USB.

My arms are supported on a tray that slides on to the arms of my wheelchair. My elbows then rest on two 1-inch Sunmate foam pads covered in fabric, which offer stability and padding.

To support the TetraMouse XA, I use a Baby Bottle Holder from Mothers 3rd Arm ( as it clamps onto my tray and offers great positioning for the TetraMouse XA. To assure that the clamp attaches tightly to my tray, we insert a piece of rubber shelf liner around the edge of the tray, between the top and bottom of the clamp.

To left-click, I click the Micro Light Switch with the edge of my left thumb. The Micro Light Switch is stabilized with a piece ot rubber shelf liner. The Micro Light Switch and rubber shelf liner sit on top of a SteelSeries QcK Gaming Mouse Pad, which pads my knuckles and offers my hand stability.

To type and work with applications, I use different onscreen keyboards depending on the platform I am using. On my iMac, I use the macOS 10.13 High Sierra Accessibility Keyboard. On my HP Laptop with Windows 10, I use the built-in On-Screen Keyboard. On my 15-inch MacBook Pro with Mac OS X 10.9 Mavericks, I use KeyStrokes ( from AssistiveWare.


Allows me basically full access to my computers, excellent control of the cursor


Somewhat slow to set up, positioning requires fine tuning, requires caregiver for setup

Access to iOS devices while using Mac computers, access to more switches for gaming