Depending on their physical abilities and needs, it is possible for a person to control a computer or a communication aid using a slight movement of their foot, an eye blink or a movement of their head. These various methods of controlling an AAC device are called access methods.

An individual with complex physical difficulties may be dependent on technology for accessing education, recreation and to manage their lives. Some people use the same access method to control a computer, to operate a Voice Output Communication Aid (VOCA), and to control a powered wheelchair.

However, someone who uses a joystick well enough to drive a wheel chair safely, may not have sufficient control to use joystick access to a communication aid or computer. In a wheelchair, the delay between joystick movement and wheelchair movement tends to iron out tremor and jerks. If the user does veer off course, there is usually no serious damage. But moving a cursor through letters, words and symbols requires much more control and a word or phrase once uttered cannot be taken back. So some people use different access methods for different activities, for example: a joystick for mobility and a switch for computer and VOCA.

Direct Access: Eye-gaze, Pointing, Pressing

We are all familiar with the direct method of access: pointing at a picture, or touching the keyboard to type out a message or to dial a telephone number. Some people who need to use an AAC system to communicate may have enough physical ability to use this direct form of access. Others may be able to point or type using a different part of their bodies such as a fist or toes instead of a finger, or maybe use a technique called eye pointing.


We all use eye-gaze from time to time, looking hard at a person or an object – it can be a more subtle way of pointing than actually pointing with a finger. For people with very little control over their bodies, eye-gaze can be a very quick and efficient method of communicating. Looking at a cup of coffee on the table might mean that the person would like to have their drink … now! Some people are able to use eye-gaze at a very advanced level to look at special symbols, words or letters printed out on a card or other display. See the section on Eye-gaze Systems.

Pointing Devices

For computers and some high-tech communication aids there are also a range of different ‘pointing devices’ which some people can use. With computers becoming more commonplace, people are familiar with using a mouse to point at icons and text on a computer screen. Some people with physical difficulties find a standard mouse difficult to use. A trackerball (sometimes called a rollerball) may be helpful if the person cannot grasp a mouse or move it over the surface of a table.

Lightpointers and infra-red pointing devices can be used with some communication aids and computers. These are worn on the head and transmit a beam of light to the equipment being controlled. The computer or communication aid responds to the light beam as if the keyboard has been touched. These are especially useful when an individual has good head control but finds other types of movement difficult. See the section on Pointers.

Adapting the Keyboard

Sometimes all that is needed to give a person with a physical disability direct access to their computer or communication aid is to adjust the settings for the keyboard, to place a keyguard over the keys, or to substitute a special keyboard for the standard one.

Most computers and many communication aids allow you to adjust the keyboard response time to make it easier for the person using it to be accurate. A keyguard, usually a sheet of perspex or metal with holes drilled in it corresponding to the keys and fixed over the keyboard, might allow an individual to use a standard keyboard without accidentally hitting the wrong keys.

Different types of keyboards are available. Expanded keyboards have larger, more widely spaced keys. Miniaturised keyboards can be suitable for people with a very reduced range of movement but with good fine motor control. There are also ergonomically designed keyboards which are easier to use for people using only one hand or a head pointer. See the section on Keyboards.

Indirect Access: Scanning

Indirect access methods such as scanning with a switch may be the best option for some people with severe physical limitations as well as a communication difficulty. The user needs to be able to activate either a single switch or a number of switches connected to the communication aid or computer. The device or the computer program must be able to accept switch input, maybe via a special interface box. The switch should be placed near any part of the body that the person can control without too much effort, such as the head, foot, knee or hand. The person selects what they want to say by activating the switch to control a moving cursor on the screen.

Scanning is a difficult skill to learn and most people are not able to use their communication aid or computer immediately without having a period of training and practise. The switch user has to learn when to press the switch, when to release it, what to do if they make a wrong selection, and so on. See the section on Switch Scanning.

Switches for Scanning

There are many different types of switches. Some switches are better for controlling scanning devices than others, and some are more useful for a particular individual than others. There are switches that provide the user with feedback that they have been activated (perhaps a click or a beep). Having some sort of feedback is usually helpful to the person using the switch, even if only while they are learning to use it.

Some switches require only the lightest of touch to activate them (useful Button switch with for people with weak or very restricted movement), while others require ‘click’ feedback quite a lot of pressure before they work (better for someone with a lot of uncontrolled, strong movements). See the section on Switches.

Importance of Getting it Right

It is very important to assess the person’s needs for special access techniques or technology, and to review their needs on a regular basis. A person’s method of access may change over time as their physical abilities alter or new options are developed. The position they are in (for example, lying in bed as compared with sitting up in a chair), the type of seating (an arm chair compared with a special supportive seat or a stool) can also affect the success of an access method. The assessment should ideally be done by a multi-disciplinary team including the person themselves, an occupational therapist and/or physiotherapist, a teacher/educationalist, and a speech and language therapist.

Assistive Technology for Living

Improving accessibility in the modern home

Adapting a home for a wheelchair can be an extensive and expensive project. When you are in a wheelchair, moving house comes with additional complications. You can’t just find a house that you like, then move in without making changes. Your choice of houses is limited by space and layout. Adaptations will need to be made. Even if you buy a house that has already been adapted, you may need to make your own adjustments. Now, homes are becoming more technologically advanced. These ‘smart homes’ offer greater control from anywhere in the property, or outside it. Smart technologies can’t change the physical features. They’re not going to make doorways any wider. However, they could change the way you interact with the house that you live in.

Could your home be more accessible if you install smart home technology?

What if you could control your heating without leaving your lounge, or switch your lights on at the touch of a button? Most smart homes are controlled through mobile phones, meaning that they can be managed from absolutely anywhere. You could turn your oven on when you’re leaving work, so that your food is cooked when you get home. When you’re on holiday, you can occasionally switch your TV on to give the illusion that you’re at home. You can program smart phones to act automatically when you’re within a certain radius. If you want the oven to switch on when you’re three miles from home, or would like the heating to switch on just after you’ve left work, then you can program in these requests. Everyone can benefit from smart home technology, but for wheelchair users this technology represents an increasing level of freedom. When you control your house with your phone, you don’t need to move around it as much. For people without speech, this smart technology becomes even more beneficial. Controls on your mobile phone will allow you to open the curtains without moving from your bed, or to start the process of cooking breakfast whilst you’re still styling your hair. You can run a bath as you finish dinner, without even leaving the table. Smart technologies can provide a level of independence that some people without speech could not otherwise experience. You can also use your phone to help with physical navigation. At the push of a button, a ramp can drop down from your front door. There are no limitations, thanks to an ever-increasing range of smart products on the market.

Why is smart home technology so valuable?

Perhaps one of the most beautiful things about smart home technology is that it is fully customisable. You only need to install the features that you’ll actually use. Better yet, this is technology that improves accessibility without requiring a certain wheelchair. Manual wheelchairs, electric wheelchairs, brand new ones and older used wheelchairs are all the same as far as smart tech is concerned. The wheelchair you’re using is not the important bit – all that matters is that you can use your phone whilst you’re in it. Some wheelchair users will need wheelchairs that feature all the latest technologies in-built. For others, perhaps a mobile phone and connected devices could be enough to make dramatic lifestyle changes. What would you like to be able to control using just your mobile phone or tablet?

Mobility Smart is an online retailer stocking a wide range of mobility aids including new and second hand wheelchairs, as well as wheelchair accessories. Many suppliers also help with accessible technology for the home and mobility. We have AT supplier members such as Mounts & More, Smile Smart Tech, Possum and more.

Find out more about Access Methods

In eye-gaze systems, the user looks at the required item on the screen and then selects that item by either pressing a switch or holding their gaze for a preset length of time.

These systems are relatively expensive, costing several thousand pounds. Several systems are available; all have different characteristics and vary in their tolerance of head movement.

An assessment and a trial with a system are imperative before considering any purchase.

Tobii C12

Alea Intelligaze

Pointers are mice, trackerballs and joysticks

There are many different versions of each available. An individual who is unable to use an ‘off the shelf’ mouse may be able to use an adaptation, for example a one click mouse or miniature mouse. There are variations is the positions of mouse buttons. Trackerballs are available with different sizes of ball, in different locations. Thus an assessment is valuable to explore the full range available.

For people who can control the position of the pointer but cannot press the selection switch, an additional ‘select’ switch can be added. Alternatively, with a dwell facility, the program will automatically accept an item without the need to press a switch, once the pointer has been held over that symbol/word/letter for a given, but changeable, time. Not all programs offer this dwell facility but it can be added using an add-on program.

Using a pointer can also be made easier by modifying the cursor. The colour, size and shape of the cursor can be modified, as well as the colour of the background. The speed of movement of the cursor and its acceleration can be changed on most computers via the control panel.

Traxsys Roller Joystick Plus

MicroTrac Finger Mouse

Keyboards are available in different sizes, shapes and layouts. Some keyboards also have keyguards which minimise the risk of to hitting an unintended key. Computers and communication aids offer facilities to slow down the repeat rate of keys, minimize repeated hits of a key (tremor) and allow the production of capital letters and other multi-key combinations (sticky keys).

Several variables may be adjusted to make it easier to operate the keyboard. Keys may be made larger or smaller. A keyguard may be added to reduce unwanted activations. Some devices allow the sensitivity of keys to be adjusted, setting a time that the key has to be held down before activating, and/or an elapse time before the next key can be activated. Some people find it helpful to select keys with a tool such as a ‘prodder’ or a head pointer.

Advice and an opportunity to explore many different options are critical to success. Fine tuning the position, orientation and pressure required to operate a device may make the difference between success and frustration.

Big Keys keyboard with keyguard

Ultra Compact keyboard with keyguard

Single switch scanning

Theoretically single switch scanning is the simplest. An indicator (highlight, cursor or light) moves through all the options, one at a time, at a speed preset to suit the the user. When the required item is highlighted, the user presses the switch and that item is selected. If the user can always hit the switch when they require then single switch scanning can be a quick and easy selection method. However, single switch scanning demands considerable concentration and physical control.

Two common difficulties are that the user may tense up as the required location is approached and therefore be unable to activate the switch, or they may be so excited that they hit the location before or after the required. Slowing the scan rate may just cause the user to lose concentration or interest.

Two-switch scanning

There are many variations on two switch scanning, but basically pressing one switch progresses the indicator systematically through the options available. When the required item is highlighted, the user presses the second switch to select the item. Hence one switch is the ‘move’ switch and the other the ‘select’ switch.

This method puts the user in total control and overcomes the tension around stopping the scan in the correct place.

Row-column scanning

Row-column scanning is much quicker than sequential scanning. Items to be scanned (i.e. the ‘keys’ or ‘cells’) are arranged in a grid. The rows of the grid are indicated one at a time. When the row containing the desired item is highlighted, the user presses a switch. The indicator then moves along the row, key by key. When the desired item is highlighted, the user presses again and the item is selected.

Row-column scanning can be used with either one or two switches.

(There are other scanning methods involving three or four switches but these are not often used.)

Simple switches are activated by pressing down on the top with some part of the body (e.g. hand, head, knee). Switches are available in different sizes, shapes and colours. Some allow the activation pressure to be adjusted.

For individuals who are unable to activate a simple switch reliably, there are a wide variety of commercially available alternatives, such as mercury tilt switches, eye blink switches, muscle movement detectors, and sip/ puff switches.

Switches need to be secured and mounted in the required position to prevent them moving or falling out of the user’s reach, and to keep the switch in a consistent position so the switching action can become automatic. The less the user has to think about the switching action, the better they can concentrate on what they actually want to do. Assessment by a qualified professional is essential to identify the best combination of switch type and switch mounting.


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