**6.3 Internal moments and forces in a wheelchair axle**

The forces and moments acting on the back hub of a wheelchair were determined a similar path as above. The greatest moment exits where the hub is welded to the frame. There are vertical forces applied on the wheel starting from the ground, there likewise might be horizontal forces that act on the wheel when the wheelchair tips over, these forces cause moments on the axle. Von Mises stresses were analyzed for the axle to take note of the critical points.

#### **6.4 Bending stress in a wheelchair axle**

At the point when a section is twisted the applied moment creates stresses in the material. On one side of the part the material is extended and in this way has tensile stresses. On the opposite side the material is compressed by compressive loading. The maximum bending moment was found to be 62.125 MPa.
