Materials requested for project.
Part | Price | Quantity | Notes | Status |
|---|---|---|---|---|
| 8 mm retention rings | 20 | From Slider-crank mechanism | Ordered; Received | |
| 8x16x5 mm bearings | 20 | From Slider-crank mechanism | Ordered; Received | |
| Aluminum plate stock (12” x 12” x ¼” plate stock) | $30.51 | 1 | 8975K142 (McMaster-Carr Part No.) | Ordered; Not Received |
| Aluminum stock (¼” x 1” x 48” bar stock for links) | $12.28 | 1 | 8975K596 (McMaster-Carr Part No.) | Ordered; Received |
| Rotary shaft 200 mm x 8 mm | 2 | From Slider-crank mechanism | Ordered; Received | |
| Rubber lining (1” x 18”) | $6.47 | 1 | 9023K82 (MacMaster-Carr Part No.) | Ordered; Received |
Above are concept drawings for the mechanism. In reality, the curved pushbar will have two points of contact with the ground and will cause the wheelchair to not be perfectly level through the motion. Two cycles of the motion may be needed to get the wheelchair fully on the ledge.
An issue to consider for the project is the scale of the final prototype or presented class product. A life-size scale for a wheelchair presents difficulties in obtaining the required materials for construction and testing, and we may look into a reduced-size model for a prototype. Another issue is the separate mechanism for engaging and operating the curb scaling mechanism, which would be necessary for a complete, functioning attachment. The scope of the whole attachment may conflict with the class timeline, but because the two mechanisms are fairly independent, a single presentable mechanism with the conclusion of the class can be manageable. A final prototype might be the curb scaling mechanism, which would demonstrate translating a wheelchair or model from the ground onto an elevated platform.
