1. Develop an understanding of the muscle loading which corresponds to given joystick designs by collecting simultaneous sEMG (surface electromyography) and joystick position data.

To monitor displacement, joysticks were outfitted with hall effect sensors and rare earth magnets (Wilson and Smith, 2001)

Two sensors are ‘activated’ for each primary motion (forward, backward left and right).

2. Develop a dynamic which includes the hard endpoint of joystick motion

• Palm and fingers are compressed between inertia of arm and joystick handle
• Palm and finger compression pose significant risk for development of carpal tunnel syndrome (Baker et al., 1990; Silverstein et al., 1986)
• Decelerations at the hard endpoint can be high, indicating potential for high compression forces on palm and fingers

To monitor force at the hard endpoint, joysticks were outfitted with three sets of strain gauges.