Submitted version of the thesis - Airlab, the Artificial Intelligence ...

3.2. Motors 25
Figure 3.3: The calculated curve for the Pololu 25:1 Metal Gearmotor 20Dx44L mm
Due to the linear inverse relationship between torque and speed, the
maximum power occurs at the point where ω = 1
2 ωn, and τ = 1
2 τs. The
maximum power output occuring at no load speed with, τ = 500rpm =
52.38rad/sec, and the stall torque, ω = 0.282Nm is calculated as follows:
P = τ ∗ω
Pmax = 1
2 τs ∗ 1
2 ωn
Pmax = 26.190rad/sec ∗0.141Nm = 3.692W
Keeping in mind the battery life, the power consumption, the necessary
torque and the maximum speed, we selected the Pololu motors shown in
Figure 3.4.
In the design of the robot we decided to use low cost components. In
that sensewefocused onproducingcomponents or re-usingcomponents that
can be modified according to our demands. The mechanical production of
the components took some time both for the design and the construction
process (e.g. the connectors between motors and wheels are milled from an
aluminum bar), however this reduced the overall cost. The connection of
motors with robot is made by putting the motor inside an aluminum tube,
merging it with the U-shaped plate (Figure 3.5). Using such a setup helps