Mobility: Stair Navigation and Turning Team MIEUX – ASME Design Competition September 23, 2004 Stefan Campbell Carlos Celada Chris Villani Laurel Weiske TEAM MIEUX

1.Power forward to contact step face 2.Rotate counterbalance to enter raised position 3.Power forward to advance front wheels past stair face 4.Rotate counterbalance to bring front wheels into contact with stair top 5.Power forward to climb stair (front wheels pull forward while rear wheels push up) Stair Ascension – 5 Steps

Stair Ascension TEAM MIEUX Vehicle drives forwardCounterbalance rotates backward Vehicle enters raised position and drives forward Counterbalance rotates forwardVehicle climbs stairVehicle proceeds onto higher stair

TEAM MIEUX

1.Rotate counterbalance to place weight on front axle 2.Reverse Down Stair – dropping rear wheels down stair face 3.Rotate counterbalance to rear of vehicle 4.Power in reverse to pull front of vehicle down stair face Stair Descent – 4 Steps

Stair Descent Vehicle drives in reverse Counterbalance rotates forward Vehicle slowly lowers itself to the next step Counterbalance slowly rotates backwards as the vehicle drives in reverse Vehicle reaches the step and adjusts the counterbalance Vehicle proceeds TEAM MIEUX

Propulsion 3 Motors 2 to power independent rear wheels 1 to power front wheels together RC/Hobby Motors not a feasible option (high speed, low torque) Drive Train Rear wheels direct power Front wheels powered by drive shaft – gears in 1:1 ration Want speed of front and rear wheels to be identical Control L.R.M and front wheels are powered together

TEAM MIEUX Propulsion Diagram

1.Rotate Counterbalance to rear of the vehicle – enter raised position 2.Power rear wheels in opposite directions to affect turning forward power to R.R.M and reverse power to L.R.M causes left turn reverse power to R.R.M and forward power to L.R.M causes right turn 3. Rotate Counterbalance towards front of vehicle – exit raised position TEAM MIEUX Turning Operations -- 3 Steps

TEAM MIEUX What do the Trade Studies give Team MIEUX? Chassis Trade study will dictate all dimensions – including wheel size and counterbalance length – determine overall vehicle weight Motor/Drive Train Trade Study – select motors to power chassis of given dimensions – select all hardware (shafts, gears, bearings) Counterbalance Trade study – Dictate shape of arm – weight required – drive linkage