2015: Year of the Mecanum

[Ether]

Originally Posted by alopex_rex

Our only experience with mecanum is with an off-season project, which had trouble going straight, we think because of wonky weight distribution.

Weight distribution is only one of many factors which can cause unsatisfactory mecanum performance.

Here are some others:

• too much roller axial free play
  
  
• too much roller spinning friction
  
  
• wheel alignment (toe-in¹, camber¹, and axial offset²)
  
  
• excessive gearbox friction (improper assembly and/or lubrication)
  
  
• chain (or belt) too tight or not properly lubricated
  
  
• warped frame
  
  
• frame too rigid
  
  
• motor manufacturing tolerances
  
  
• motor controller calibration

¹Toe-in and/or camber of a wheel causes the wheel sprocket (or pulley) to be non-coplanar with the driving sprocket (or pulley), and thus contributes to friction between the chain (or belt) and the sprocket (or pulley). Toe-in also causes scrubbing friction with the floor surface.

²"wheel axial offset" in this context means that the wheel sprocket (or pulley) is axially offset from the plane of the driving sprocket (or pulley), causing the chain (or belt) to be non-coplanar, thus creating additional friction between the chain (or belt) and the sprockets (or pulleys).