In sumo robot or combat robot competition where high holding torque's motor is essential to avoid your robot being pushed by your opponent robot. The worm gear is definitely a better option compared to the spur gear motor. Why is worm gear so special? Check this wiki out: Worm Drive.
"Unlike with ordinary gear trains, the direction of transmission (input shaft vs output shaft) is not reversible when using large reduction ratios, due to the greater friction involved between the worm and worm-wheel, when usually a single start (one spiral) worm is used. This can be an advantage when it is desired to eliminate any possibility of the output driving the input."
In other words, it is difficult to push your load (example, your robot) if the motor is not power or rotate.
Features and Spec:
- Metal gear box
- Output shaft is self-locking due to the worm gear's characteristic
- Rated voltage: 12V DC
- Rated output speed: 150 RPM
- Rated output torque: 117mN.m (1.2kgf.cm)
- Stalled torque: 196mN.m (2kgf.cm)
- No load current: 60mA
- Stalled current: 1.8A
- Output shaft diameter: 6mm with 4.5mm slot
- Weight: 150g
|Speed (RPM)||101 - 200|
|Torque (kgf.cm)||1.01 - 2.00|