22-Mec-A3 System Analysis and Control
Worked solutions to 13 past sittings (2013–2019), 79 questions. Pick a sitting, or start from a topic below.
- December 2019
- December 2018
- May 2018
- December 2017
- May 2017
- December 2016
- May 2016
- May 2015
- December 2014
- May 2014
- December 2013
- May 2013
- Undated paper
Topics across the sittings
Topics that come up in more than one sitting, taken from the headings of our worked solutions. A topic counts once per sitting.
- Steady-State Error (6 sittings): December 2018 Q7 · December 2017 Q3 · December 2016 Q6 · May 2015 Q3 · December 2013 Q3 · May 2013 Q1
- Root Locus (5 sittings): December 2019 Q6 · May 2018 Q4 · May 2015 Q4 · December 2014 Q1 · May 2013 Q5
- Step response (4 sittings): May 2018 Q1 · December 2017 Q1 · December 2016 Q5 · May 2013 Q1
- DC Gain (3 sittings): December 2018 Q1 · May 2017 Q1 · May 2016 Q1
- Asymptotic Bode magnitude plot (2 sittings): May 2015 Q1 · December 2013 Q6
- Bode Diagrams (2 sittings): December 2019 Q5 · December 2016 Q3
- Bode Magnitude (2 sittings): May 2017 Q6 · May 2016 Q4
- Bode plot (2 sittings): December 2018 Q4 · May 2014 Q1
- Error Constants (2 sittings): December 2018 Q7 · December 2016 Q6
- Gain margin (2 sittings): May 2014 Q1 · December 2013 Q6
- Phase margin (2 sittings): May 2014 Q1 · December 2013 Q6
Questions by sitting
December 2019
- Question 1: Direct Laplace Transforms of Differential and Integral Equations
- Question 2: Two-Phase AC Servomotor Positioning System
- Question 3: Steady-State Error of a Type-2 Loop
- Question 4: Routh–Hurwitz Stability of Three Feedback Loops
- Question 5: Bode Diagram and Unconditional Stability of a Second-Order Servomechanism
- Question 6: Root Locus and Critical Gain of a Three-Pole Loop
December 2018
- Question 1: DC Gain and Final Value of an Unstable Second-Order System
- Question 2: Routh Stability Range for a Tape-Drive Servo
- Question 3: Root Locus of $k/[s(s^{2}+6s+12)]$
- Question 4: Bode Plots and the Gain Margin at 45° Phase Margin
- Question 5: Laplace Solution of Two Differential Equations
- Question 6: Step Response from a Pole–Zero Description, and an Inverse Transform
- Question 7: Error Constants and Steady-State Errors
May 2018
- Question 1: Closed-loop transfer function, poles and zeros, step response
- Question 2: Steady-state error with a pre-loop gain
- Question 3: Routh–Hurwitz test with a vanishing row
- Question 4: Root locus — breakaway and break-in points
- Question 5: Gain for a specified damping ratio
- Question 6: Bode diagrams of two loop transfer functions
December 2017
- Question 1: Impulse and Step Response; Free Response of a Second-Order ODE
- Question 2: Routh Stability — Range of Gain and an Open-Loop Unstable Plant
- Question 3: Steady-State Error — Recovering G ( s ) and the Effect of Gain and Damping
- Question 4: Root Locus of a Four-Pole Plant and its Imaginary-Axis Crossings
- Question 5: Lead-Compensator Design for Specified Damping and Natural Frequency
- Question 6: Bode Diagram of a Resonant Plant; Gain Design for a Specified Phase Margin
May 2017
- Question 1: DC Gain and Final Value of an Unstable Second-Order System
- Question 2: Routh’s Criterion Applied to Two Unity-Feedback Loops
- Question 3: Compensator Constraints for Type 1 Behaviour and Robust Stability
- Question 4: Motor Position Control — Velocity Constant, Damping Ratio and Ramp Error
- Question 5: Root Locus of a Third-Order Loop — Segments, Asymptotes and the Imaginary-Axis Crossing
- Question 6: Bode Magnitude and Phase Asymptotes for Two Open-Loop Transfer Functions
December 2016
- Question 1: Impulse Response of a Repeated-Pole and of an Underdamped System
- Question 2: Steady-State Level of a Proportional Liquid-Level Loop
- Question 3: Bode Diagrams — a Lag Network and a Three-Pole Loop
- Question 4: Root-Locus Design for a Damping Ratio of 0.5
- Question 5: Routh–Hurwitz Stability, Step Response and Gain Tolerance
- Question 6: Error Constants and Steady-State Errors
May 2016
- Question 1: DC Gain and Final Value of a Second-Order System
- Question 2: Inverse Laplace Transforms by Partial-Fraction Expansion
- Question 3: Routh Stability Range and Root Locus for System 1.0
- Question 4: Bode Magnitude and Phase Asymptotes
- Question 5: Steady-State Error Specifications for a Position Control System
- Question 6: Counting Right-Half-Plane Roots with Routh's Criterion
May 2015
- Question 1: Asymptotic Bode Magnitude Plots
- Question 2: Unit Step Responses by Partial Fractions
- Question 3: Proportional Temperature Control — Type Number, Gain and Steady-State Error
- Question 4: Root Locus and Steady-State Error with Rate Feedback
- Question 5: Routh–Hurwitz Stability Determination
- Question 6: Effect of Loop Gain on Step Response and Steady-State Error
December 2014
- Question 1: Root Locus and Range of Stabilising Gain
- Question 2: Bode Diagrams of Two Transfer Functions
- Question 3: Sinusoidal Steady-State Response of a First-Order System
- Question 4: Routh–Hurwitz Root Counts
- Question 5: Transient Terms of a Two-Input Servo with Rate Feedback
- Question 6: Steady-State Errors of a Motor Position Servo
May 2014
- Question 1: Bode plot, gain margin and phase margin
- Question 2: Routh–Hurwitz ranges of a parameter
- Question 3: Root locus for positive and negative gain
- Question 4: Transient-response terms under proportional control
- Question 5: Steady-state errors for step and ramp inputs
- Question 6: Sinusoidal steady-state response of a first-order system
December 2013
- Question 1: Unit step response, and the time constants of a transient
- Question 2: Routh–Hurwitz gain limit and the poles at that limit
- Question 3: System type, loop gain and steady-state errors
- Question 4: Motor position servo with and without rate feedback
- Question 5: Root locus of an unstable plant and the gain range for stability
- Question 6: Asymptotic Bode magnitude plot, phase margin and gain margin
May 2013
- Question 1: Unity-feedback system — real-pole range, step response, steady-state error
- Question 2: Type-1 system — gain for a ramp-error spec, then step/ramp errors
- Question 3: Routh–Hurwitz stability range of a fourth-order loop
- Question 4: Stability range, and the stabilising effect of a feedback zero
- Question 5: Root locus and the gain for $\zeta=0.5$
- Question 6: Bode design of a plant zero location for a target gain-crossover
Undated paper
- Question 1: Routh–Hurwitz stability of two characteristic equations
- Question 2: Impulse response of two transfer functions
- Question 3: Steady-state response of a proportional liquid-level loop
- Question 4: Absolute stability of a hydraulic servo by Routh’s criterion
- Question 5: Bode diagrams of two open-loop transfer functions
- Question 6: Root-locus plots for two open-loop transfer functions