Instructions on how to build part of the wheelchair lever arm in solidworks for this project:
Step 1: Create a Sketch of the Ratchet Shape on the Front Plane
Make a rough sketch of the part by using the line and arc tools. The line tool is used to create the shape of the teeth while the arc gives the ratchet length and curvature. Use the mirror tool to make the sketch exactly symmetrical.
Step 2: Use "Extrude Boss" to Extrude the Base 20mm
Step 3: Create a Reference Plane for the Teeth
Create a reference plane on the top side of the ratchet and draw a rectangle. The points of the rectangle should connect the inner corners of the two arcs and be large enough to extend the length of the tooth.
Step 4: "Extrude Cut" the Rectangle 10mm Downwards
Repeat this step on the other side of the ratchet but draw the rectangle on the original plane and extrude cut upwards 10mm.