#### Friction

lesson

All mechanical systems exhibit friction and we learn about two broad classes of friction: linear and non-linear.

lesson

All mechanical systems exhibit friction and we learn about two broad classes of friction: linear and non-linear.

lesson

If your knowledge of dynamics is a bit rusty then let’s quickly revise the basics of second-order systems and the Laplace operator. Not rusty? Then go straight to the next section.

lesson

We will use Simulink to create a dynamic model of a single robot joint and simulate its operation.

lesson

We can model a DC motor as a resistor and a voltage source, and then understand the implications of controlling either the voltage or current supplied to the motor. We also learn about common methods for motor control such as the H-bridge driver and pulse width modulation.

lesson

We will learn about the forces that are exerted on a robot’s joint by gravity acting on links, friction, and the coupling forces where the motion of one joint imparts a force on other joints.

lesson

A number of strategies exist to reduce the effect of these coupling torques between the joints, from introducing a gearbox between the motor and the joint, to advanced feedforward strategies.

lesson

We will introduce resolved-rate motion control which is a classical Jacobian-based scheme for moving the end-effector at a specified velocity without having to compute inverse kinematics.