1. Gears: the lighter the gear the better motion, less torque and higher speed. Some of this model is spur helical, bevel, worm, rack and pinion, and many others
Gear picture
2. Chains:
3. Timing belts: have some kind of teeth and these teeth go around with some kind of pulley that drives this belt around it to transfer motion. It is used nowadays with robot walking machine
Timing belt with a pulley
Timing belt connected to a pulley
4. Metal belts, cables and pulleys
5. Linkages:
Robot example of linkages between a servo motor and pulleys
6. Ball screws: are very important to create linear motion backward and forward with low speed. We can use some kind of nuts, by tightening the nut we control the speed of motion
