Page 141 - Handbook of Electronic Assistive Technology

Chapter 5 • Alternative Access Technologies 129

Chloe’s Case Study
Chloe is 3 years old and has a congenital limb deformity: she has no arms or legs. She
does, however, have excellent control over a single left toe. At nursery school, she is using
an Easy Cat Glidepoint Touchpad to access the class laptop and access the activities that
her peers are enjoying via the interactive whiteboard. The Easy Cat is placed on her seat
cushion so that she can access it with her toe. The touch surface measures 61 mm × 46 mm
and Chloe can reach across the surface with her toe, and achieve control over the mouse
pointer. She taps and drags to operate the mouse buttons.
Many trackpads are now multitouch and therefore permit use of gestures to, for exam-
ple, turn on the drag lock, zoom in and out or scroll.

Trackpad Settings
Some common trackpad settings are given in Table 5-4.

Pen Tablets
Pen tablets are primarily designed for use with drawing and painting programs and are
controlled with a stylus or finger. They are larger than trackpads (e.g., 150 mm × 95 mm
compared to a modern laptop touchpad of around 105 mm × 75 mm), which, coupled with
the pen, offers very precise control over the mouse pointer. Some people who experience
pain when using a mouse prefer a touch tablet and stylus because it requires more com-
plex and fewer repetitive movements and is therefore more comfortable.
Ergonomic Mice

Computer mice are available in a large variety of sizes and shapes. Ergonomic mice are
claimed to reduce the risk of pain or damage due to repetitive movements, by encouraging
healthier positioning and movement.

Head-Controlled Pointing Devices

Some people do not have any control over upper or lower limbs (e.g., due to spinal injury),
and have good head control. Others, perhaps with cerebral palsy, may be able to move
their head more accurately than other parts of their body.

Table 5-4 Trackpad Access Settings
Trackpad Access Option What It Does Why It Is Useful
Tracking speed Adjusts the speed of movement of Users who have difficulty pointing accurately
the pointer on screen. may find it easier if the speed is slowed down.
Tap to click Turns tap to click on or off. Turning off tap to click may avoid unwanted
mouse clicks.
Secondary click Tap with two fingers to right click. Gives access to right click by just using the
trackpad.