Assistive Technology - Tools and Applications 3

The Mouse

The standard mouse requires fine motor control and is often difficult to operate initially, even for non-disabled people.

The mouse properties in the Windows Control Panel can significantly help by reducing the double-click speed, the motion of the pointer and the pointer size. Also, by using the MouseKeys function, the numeric keypad on the standard keyboard can control the mouse. These mouse-property options should be considered initially, as they reduce dependency on accurate mouse control and may allow computer use without recourse to alternative mice. They are set from the Accessibility Options in the Windows Control Panel, and the instructions can be found in the Help section of the Start menu (type 'mousekeys' in the 'Index' menu). If this proves to be an option, the commands must be learned.

MouseKeys

• To click (for example, on a menu command), press 5 on the numeric keypad.
• To double-click, press the PLUS SIGN (+) on the numeric keypad.
• To right-click, press the MINUS SIGN (Ð) on the numeric keypad, and then press 5 to click, or press the PLUS SIGN (+) to double-click.
• To click as if using both mouse buttons at once, press the ASTERISK (*) on the numeric keypad, and then press 5 to click or the PLUS SIGN (+) to double-click.
• To switch back to standard clicking, press FORWARD SLASH (/) on the numeric keypad.

If the standard mouse is not an option, alternatives must be explored and there are many of these. When one considers what the mouse actually does, the task of replicating its functions does not seem so difficult. The basic mouse is used to position the pointer at a certain part of the monitor (select option), and to command (or click/double-click) the computer to do something.

Trackerballs

(also called trackballs, or rollerballs) are an alternative form of mouse with the roller on top, rather than on the bottom. Because the mouse remains stationary, less movement is required and a large ball on top is rolled to move the pointer. Prominent buttons can perform the click functions and some have latching (or draglock) capacity which will be necessary in many cases.

Trackerball mouse

Joystick

The joystick is the next level of possible manipulation of the pointer. The joystick moves the pointer, and those designed for special needs will dampen down random motions and the movement of the pointer will be less erratic. Various arrangements of buttons and latching are available, along with horizontal/vertical12 control and button guards.

A Mouth operated joystick is controlled by the mouth and clicking can be achieved by bite, puff or sip switches.

Joystick mouse

Footmouse

Operated by the foot, the footmouse has all the features of a normal mouse.

Headmouse

A head-mouse works by a transfer of infrared signals from a small dot placed on the forehead that can control a pointer on the computer monitor. It requires relatively fine head control. When this capability is combined with an on-screen keyboard, the head-mouse can replicate the functions of a conventional keyboard and all of the standard computer applications are available to the user.

Headmouse Controller

Touchpads

These have become popular on laptops, but standalone touchpads are available as a mouse alternative. The monitor pointer is operated by limb movement across a touch pad, and the clicking function by tapping on buttons or on the pad. Touchpads are useful for people that might have fine finger control, but lack gross hand movement.

A 'Y Connector' provides an additional input socket, allowing the use of a standard and alternative mouse on one computer.