Why is low wattage good?

Ive been told by my mentor teams that motors will ideally want to run under 1 watt, but why is that? I know that it is good I just want to understand why it is so i can document it in the nb and such.

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I suspect what they are discussing is the power consumed by the motor when the mechanism is unloaded. This is a good indication of losses in your system (primarily friction).

A couple of key points to be aware of:

  • The mechanism is unloaded
    • Drivetrain wheels are not touching the ground
    • A conveyor belt is not carrying any game objects
    • An arm is not lifting anything beyond itself
  • The power reported is how much power is ‘lost’ in the mechanism
    • This power is not available for doing ‘useful’ work
    • Higher losses also lead to motors overheating more quickly
  • The primary culprit in this measurement is friction
  • A number of design and build issues can make this much worse
    • Bent shafts
    • Crooked shafts (bearings offset from one another)
    • Misaligned bearings (3 or more bearings that are not perfectly aligned)
    • Excessive side loads (shafts being forced sideways in the bearings)
      • Shafts with very high side loads (like pivots on a large lift) can benefit from ball bearings
    • Slop in the structure (does it bend when you push on it?)
    • Unsupported gears
      • Gears try to push away from each other under load
      • If this is not well restrained you can end up with bearing friction and skipping gear teeth

This is not a comprehensive list, but hopefully it is a starting point.

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That would be a great lesson for your teacher to explain. They could roll into it when to pick the 5w or the 11w motors.

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