Capability simulators are devices that designers can use to reduce their ability to interact with a product.

• Physical simulators are devices that can be worn to impair movement or vision
• Software simulators modify an audio clip or photo image, so that someone who is fully able perceives the information as though he or she has a capability loss

These simulators can provide a quick and cheap method to help designers empathise with those who have capability losses, increase their understanding of the different losses, and simulate how exclusion occurs during product interaction. The cost, speed and ease of access means that these simulators can be used both early on and repeatedly throughout the design process.

However, no simulator can ever truly model what it is like to live with a particular capability reduction on an everyday basis. In addition, the decline in cognitive ability, and the effect of the user’s past experience cannot be meaningfully reproduced by simulation. Simulators are helpful to increase empathy with users who have reduced capability, but should never be considered as a replacement for involving real people with such losses.