Control System Analysis Preview

Professional control systems engineering example using step response analysis

R(s)K1s(s+1)C(s)+-Unity Feedback Control System

Unity Feedback Control System

Problem: Analyze the step response of a unity feedback control system with plant transfer function G(s) = 1/(s(s+1)) and unit step input.

System Characteristics:
  • • Type 1 system (zero steady-state error for step)
  • • Second-order system with poles at s=0, s=-1
  • • Closed-loop response: C(s)/R(s) = 1/(s(s+1))

Applications: Robotic positioning, drone autopilots, industrial automation

Analyze the Step Response

Find the time-domain response when this system is excited by a unit step input

Quick examples:

Enter a function above and click "Compute" to see results

Control Systems Fundamentals

The transfer function G(s) = 1/(s(s+1)) represents a common second-order plant with an integrator. The step response reveals critical system behavior.

Expected Response:

  • • Final value: 1 (zero steady-state error)
  • • Rise time: depends on dominant pole
  • • No overshoot (critically stable)
  • • Exponential approach to steady state

Key Insights:

  • • Pole at origin provides zero steady-state error
  • • Real pole at s=-1 determines settling time
  • • Response: c(t) = 1 - exp(-t)

Understanding step response helps engineers design controllers for desired transient and steady-state performance.

Industry Applications

SpaceX Falcon Rockets

Attitude control systems use similar transfer functions for precise rocket orientation during flight and landing.

Industrial Robotics

Boston Dynamics and factory automation systems use step response analysis for precise robotic positioning and movement control.

Autonomous Vehicles

Tesla Autopilot and Waymo use control system analysis for steering, acceleration, and braking system responses.

Drone Flight Control

DJI and military drone manufacturers analyze step responses for stable hover and precise maneuvering capabilities.

Expected Step Response Analysis

Rise Time

Time to reach 90% of final value

≈ 2.3 seconds

Steady State

Final value after settling

1.0 (0% error)

Overshoot

Maximum overshoot percentage

0% (No overshoot)

Want to compare with the RLC circuit example?

See how electrical engineers analyze oscillatory responses in power systems