Switches for All

Technology, when used wisely and appropriately, can open the doors to writing, communicating and interacting for the disabled. It can create new possibilities and options in the school and work environment. It can improve productivity and improve functional skills.

New technology clearly offers great promise for all, especially those with disabilities. Our challenge is to find the resources and wisdom to use it and to apply the use of new technology appropriately.

In the last few articles we looked at Input Devices such as the keyboard, joystick and head-mouse. Over the next few articles we will be looking at switches.

Single impulse

A switch, in its simplest definition, is an electromechanical device that is used to activate or deactivate an electrical signal. By opening or closing a contact, a switch can provide a single electrical connection to provide transmission of a single impulse. On its own it does not replace a mouse or keyboard, yet together with a software application, it can be made possible.

There are many uniquely designed switches which can be ingeniously used to enable a severely disabled person to do things which would be impossible without the switch interfacing with the appropriate software application. A switch bridges the gap between the person with a disability and the equipment and the function to be performed. Adaptive switches, with the right software applications (such as computer programs, communication devices, toys, environmental control systems, electronic aids to daily living), can open up a whole new world of horizons and opportunities for people with severe physical disabilities.

Switch + application = skills, functions, new opportunities.

Making tasks simpler

For people with mild to moderate physical disabilities and other cognitive, learning or sensory problems, switches can also assist with making tasks simpler, quicker and easier to understand.

There are SO many options out there for adaptive switches and the types of activities and functions they can control. So it is important to be aware of the wide range of switches that are available, as well as the types of programmes and activities which can be performed using them (the switch + application options).

In addition, we should be continually striving to use switches and applications creatively to establish the most effective system which will provide maximal opportunity for the user with a disability. There are some important points to consider when selecting a joint movement and control site for switch placement:

Small, Controlled Movement

The movement should be as small and controlled as possible, using the least amount of energy and effort. Only a small, controlled movement can be repeated many times without causing excessive stress on the joints or resulting in fatigue.

Motor Learning and Skill Development

Learning to activate and control switches is the same as any other motor skill learning - it requires time, many, many switch hits per day (in the hundreds...), repetition of the same movement, and perseverance as in learning any new physical skill.

Low Profile and Unobtrusive

Another reason for opting for smaller switches is that the switch itself should not be 'the activity'! The switch should become 'transparent'. It should be simply a means of 'making something happen', participating, communicating and being involved in other activities. The switch should be out of the way of all activities, not interfering with placement of objects; it should not obstruct visual contact with activities or communication partners.

Visual Targets!

If at all possible, the switch should be positioned so that the user can access the switch without looking for it. If a user spends time and effort looking for and trying to access it, visual contact and attention strays from the communication partner or activity, which is counter-productive.

Extended Use Set-ups

For many users, switches are the only means of access to many activities during the day. If possible, switch controls, types of movements and position sites should be selected keeping in mind the need for use at all times. For those who need to change switch positioning, these should be quick and easy to set up and move. For those who need access to a switch or switches all day, make sure they are accessible in all environments and positions.

In the next few articles we will be looking at assessment, how to find the best switch or control site, and various switches, switch interfaces and software applications.

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