1. Group 11- ASME Design Competition
Alicia Christie
Desmond Bourgeois
Toddrick Ruff

2. ASME Design Competition
Rule Update
Rocks do need to touch receiving area
1 rock in each circle
 Score
S = Σ (R*t) +1000P - W - A T – 5s
R = designated rock score  t = target multiplier  W = Weight of the vehicle in grams  A = milliamp-hours available to the device according to the battery labels  T = Times device touches border tape  s = seconds to complete task, maximum 240  P = bonus for parking vehicle at end of task (1 = parked, 0 = not parked)
Schematic of Test Course
2 – 1700 pt rocks
1 – 1600 pt pt
2 – 1000pt

3. Decision from Last Presentation
3 – Wheel Design
Street Sweeper
Mechatronics, Ariel University Center

4. Design Concept
rotate
move

5. r + 2*cos(30)*[r+s/2] = 3.75 in
Wheel set distance D = 4r + s : if r = 1 in, s = 1.18 in, D = 5.18 in
D*2 + 4 in (box size with guides in back) = in
with wheels and box touching
Max length is 14.5 in

6. Design Concept ?

7. Final Design Wheels are offset with front wheels on inside barrier

8. Idea for body expansion
Switch blades
Approximate
Extension Length

9. Interim Prototype

10. 3 Wheel Operating Principle
Exploded View
Assembled View

11. Gear Force Analysis Assumptions Const. load with uniform shock
Const. mesh with no backlash
Axial load is negligible
Qv < 5, low pinion velocity < 13m/s
99% reliability
Full-depth teeth with tip loading
Pressure angle 20º
Operating temps < 200º
Teeth form standard AGMA profile
Radial
Tangential
Axial

12. Gear Force Analysis
Given
Resulting Forces

13. Rock Collector

14. Free Body Diagram Position #1 Assumptions Weight of box = 2lbs
Weight of Front = 7lbs
Tipping will not occur on back wheel
3lb
2lb
3.5in
1.5in
5.9in
10.225in
∑M = ∑F*d
M = lb-in, moment created by rock collector would have to exceed this limit to tip over giving a negative moment

15. Cost Analysis

16. Cost Analysis
Current Total: $943.70

17. Future Plan FEM Analysis to determine ways to remove material
Exact gear placement to minimize motor use
Power input and velocity calculations
Exact placement of wheels and expandable body to fit within size requirement
Placement of batteries and motors
Control configuration
Amount of motors, gears, other control components
Program control components