IntermediateTopic 61 of 102Manufacturing, Robotics & Systems
Robot actuators and drives
Servo motors, gearboxes and harmonic drives power joints.
In depth
Robots use servo motors (BLDC/PMSM) with encoders and gearboxes (harmonic drive: zero backlash, high ratio; planetary; cycloidal), hydraulics for heavy payloads, and series elastic actuators for safe interaction. Selection from torque-speed requirements, inertia matching, thermal duty and backlash.
Key points
- Gear ratio and inertia reflection
- Torque density
- Brakes
ExampleA harmonic drive gives 100:1 reduction in a compact joint.
Actuators and drives set how a robot joint moves, so their choice decides speed, torque, precision and cost.
What is Robot actuators and drives?
Servo motors, gearboxes and harmonic drives power joints.
Why is it important to understand robot actuators and drives?
Actuators and drives set how a robot joint moves, so their choice decides speed, torque, precision and cost.
What is a harmonic drive?
A compact gear reducer with high ratio and low backlash, which is common in robot joints.
Why use a servo motor?
It has feedback from an encoder, so the controller can accurately control position, speed and torque.
How is Robot actuators and drives used in practice?
Typical applications include choosing a servo motor with a harmonic drive for a precise joint, using a direct drive motor in a high precision stage and selecting a belt drive for a long arm with low loads.
What should I learn before Robot actuators and drives?
Study "Trajectory planning" first (topic 60 of 102 in Manufacturing, Robotics & Systems). It covers the groundwork this topic builds on.
What are the key points of Robot actuators and drives?
Gear ratio and inertia reflection. Torque density. Brakes.
Can you give an example of Robot actuators and drives?
A harmonic drive gives 100:1 reduction in a compact joint.
What comes after Robot actuators and drives?
The next topic is "End effectors and grippers", which builds directly on this one.
How difficult is Robot actuators and drives?
It is classed as Intermediate in Manufacturing, Robotics & Systems (topic 61 of 102). It is an intermediate topic. Work through the beginner topics in Manufacturing, Robotics & Systems first.