AWS DevOps Motion Control & Kinematics 4

Question 1

What is the workspace of a robotic manipulator?

Accepted Answer

The set of all reachable end-effector positions and orientations

Answer

The workspace is the complete set of poses the end-effector can achieve given all joint-limit constraints.

Question 2

In a ball-screw linear actuator, what determines the relationship between motor rotations and linear travel?

Accepted Answer

Lead (pitch × starts) of the screw

Answer

The lead defines how far the nut travels per full screw revolution, directly linking rotary to linear motion.

Question 3

Which kinematic chain type has its end-effector constrained by multiple independent legs attached to a fixed base?

Accepted Answer

Parallel manipulator

Answer

Parallel manipulators such as the Stewart-Gough platform use multiple legs in a closed-chain arrangement for high stiffness.

Question 4

An encoder outputs 2000 pulses per revolution. If quadrature decoding is used, what is the effective resolution?

Accepted Answer

8000 counts/rev

Answer

Quadrature decoding counts all four edges of the A/B pulse pair, multiplying the base count by 4 (2000 × 4 = 8000).

Question 5

In a PID position controller, persistent steady-state error after a constant disturbance is eliminated by which term?

Accepted Answer

Integral (I) term

Answer

The integral term accumulates error over time and outputs an increasing correction until steady-state error reaches zero.

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