Upper Extremity Design Update March 23, 2007

Device Description Acrylic beam guides motion Bungee cord with ratchet provides adjustable force Backpack frame provides stability and base for vertical and horizontal adjustment

Solid Works Drawing

Material Selection Material changed from acrylic to acetal Chemical and sunlight resistance promote longer life Material properties (tensile modulus, fatigue strength, yield stress) well-suited to required dimensions

Material Selection 3/8” beam requires a width of 5 inches at the base to satisfy fatigue strength requirements Tapered width from 5” at base to 3” at end produce adequate deflection at max force (10 lbs.)

Testing Each Rotation is counted as one repetition Rotation Motor

Testing .146H Total Arm = .186H+.146H .186H .146 H .186H .146H x .186H For 95%tile Male x=15.17 inches

Contingency Plans Telescope Issues Resiliency of Bungee Cord Beam Behavior Backpack Modification

Schedule

Facility Redesign Objectives Reduce Avg. % of halos overlapping with other halos. Reduce Avg. % of halos overlapping other equipment by at least 50% (9.5%)

Monitor improvements Improve utilization of cabinets and shelves. Reduce frequency therapist avoids an obstacle. Currently 50% of related activities Availability of equipment Currently 25% obstructed/unavailable. Increase therapy space Currently therapy space 580 sq. ft.

Summary of Current Layout Equipment Halo area (in.^2) Halo Area interfering with others (in.^2) %halo area interfering with other halos Halo area Interfering w equipment (in.^2) %halo area interfering with other equipments UBE 2400 2298 95.75% 185.4 7.73% Bike 6552 4992 76.19% 2106 32.14% Treadmill 8888 7380 83.03% 1299 14.62% Treadmill w assistance 11466 7410 64.63% 859 7.49% Steps 9792 5094 52.02% 1281 13.08% Mat 1 4680 1320 28.21% 927 19.81% Walking Bars 23352 N/A Table 2880 Mat 2 2052 43.85% Plint 1 10032 2850 28.41% 2736 27.27% Plint 2 10374 798 7.69% 3192 30.77% Plint 3 1482 14.77% Plint 4 Rack 2100 570 27.14% 456 21.71% Cabinet 1 4320 13.19% Cabinet 2 Conference table 14432 4451.5 30.84% 2816 19.51%   Average 41.46% 18.99% Std Dev. 28.51% 8.48%

Schedule

Ramp Modification Solution: Add wheels and handles to make the ramp and platform easily movable Before modification: 50 lbs. of force required After modification: 16.7 lbs. of force required