Figure 8

Experimental setup. The right arm was fixed with Velcro straps. Thumb movements were measured by two miniature uni-axial accelerometers that were mounted on the proximal phalanx of the thumb, in orthogonal planes. Electromyographic activity from the thumb muscle (abductor pollicis brevis), index finger muscle (first dorsal interosseus), and wrist muscle (flexor carpi radialis; not visible on photo) was recorded using adhesive Ag/AgCl surface electrodes.