56:1 Metal Gearmotor 20Dx42L mm
These small brushed DC gearmotors can deliver a lot of power for their size. This version has a 6V brushed DC motor combined with a 56:1 metal spur gearbox. The gearmotor is cylindrical with a diameter of 20 mm, and the D-shaped output shaft is 4 mm in diameter and extends 10.7 mm from the face plate of the gearbox.
Key specs at 6 V: 250 RPM and 250 mA free-run, 45 oz-in (3.3 kg-cm) and 3.2 A stall.
Alternatives available with variations in these parameter(s): gear ratio Select variant…
|Description||Specs (8)||Pictures (4)||Resources (3)||FAQs (2)||On the blog (1)|
Dimension diagram for the Pololu 20D mm metal gearmotors (172k pdf)
Note: This dimension diagram only applies to our older versions with shorter output shafts (gear ratios 29:1, 56:1, 73:1, and 154:1 only).
3D models of 20D mm gearmotors (1MB zip)
This file contains 3D models (in the step file format) of the 20D mm gearmotors. Note: these models only accurately represent to our older versions with shorter output shafts (i.e. gear ratios 29:1, 56:1, 73:1, and 154:1).
MATLAB script to plot motor performance curves for Pololu brushed DC gearmotors
This MATLAB script, written by Ali Asgher Mansoor Habiby, plots speed, power, current draw, and efficiency as they vary with torque when you input the gearmotor specifications. It also prints the resistance of the motor, and the current draw and torque at which maximum efficiency and maximum power occur.