PID Control Loop

Prompt

A PID feedback control loop, drawn left-to-right.

Inputs and signals:
- Reference set-point r(t) on the far left.
- Summing junction (circle with + and -) computes error e(t) = r(t) - y(t).

Controller block (PID):
- Three parallel paths labeled P, I, D, summed at the controller output u(t).
- Each path has its gain (Kp, Ki, Kd) labeled.

Plant block:
- Receives u(t) and produces output y(t).
- A disturbance signal d(t) enters as an additive arrow into the plant.

Feedback path:
- Sensor block (with sensor noise n(t) added) feeding y_measured back to the summing junction.

Annotations:
- Each block labeled with its transfer function.
- Time-domain signals labeled at every arrow (r, e, u, d, y, y_measured).

Style: classic controls textbook style, monochrome with one accent color, white background, thin connectors and clearly labeled summing junctions.

When to use

For controls / robotics / process-engineering courses and papers.

Variations

Tips

• Always show the disturbance entry point. Without it, the loop misses real-world realism.
• Use a + / - summing junction with explicit signs. Implicit signs are a common reader mistake.
• Label the sensor noise. It is the canonical reason why textbook PID is harder in practice.

FAQ