Principles of Work Design: Machines and Equipment

• Take multiple cuts whenever possible by combining two or more tools in one, or by arranging simultaneous cuts from both feeding devices

• Use a fixture instead of the hand as a holding device

• Locate all control devices for best operator accessibility and strength capability

• Use shape, texture and size coding for controls

• Use proper control size, displacement and resistance

- Control-response ratio (C/R ratio)

amount of movement in a control / amount of movement in the response

- Range effect – the tendency to overshoot short distances and undershoot long distances

- Control - resistance feedback

• Ensure proper compatibility between controls and displays

Compatibility – relationship between controls and displays that is consistent with human expectations