Temiloluwa Shokunbi
Cruise Control Lab 1
System Dynamics Lab 1:
Cruise Control Model
11 February 2025
Temiloluwa Rosetta Shokunbi (346275)
Professor
UPEI Faculty of Sustainable Design Engineering
ENGN 3820 – System Dynamics
University of Prince Edward Island
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Temiloluwa Shokunbi
Cruise Control Lab 1
Question 1 – 4.
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Temiloluwa Shokunbi
Cruise Control Lab 1
5. Use MATLAB to find the response of the velocity of the car over 100 secs for the case in which the
input “u” jumps from being u = 0 at time t = 0 to a constant u = 500 N thereafter. Assume the car’s mass
m = 1000 kg and viscous drag coefficient b = 50 N·sec/m.
6. Using the same input force u as in (5), modify the system parameters as follows:
→ Set the car's mass m to the first three digits of your ID number (in kg) System Dynamic with
Simulations
→ Set the viscous drag coefficient b to the last three digits of your ID number (in N·sec/m).
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Temiloluwa Shokunbi
Cruise Control Lab 1
→ Compute and analyze the velocity of the car after 100 seconds.
6b) Next, reverse the parameters:
→ Set the mass m to the last three digits of your ID number (in kg).
→ Set the viscous drag coefficient b to the first three digits of your ID number (in N·sec/m).
→ Compute the velocity of the car after 100 seconds.
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Temiloluwa Shokunbi
Cruise Control Lab 1
7. Analysis and Observations:
→ Compare the velocity responses obtained in (5) and (6).
Number 5 has a faster velocity as compared to the velocity response in number 6. As seen in
number 5, the velocity starts at zero then slowly increases to
→ Discuss the effect of varying b and m on the system's response.
Increasing the viscous drag coefficient (b) reduces the velocity of the system’s response. This is
shown in both graphs of number 6. Increasing the mass also reduces the system velocity response
as well. However, the velocity response is still faster in number 5. This is because the viscous
drag coefficient is still quite low as compared to number 6.
Therefore, increasing the mass but reducing the damping of the system affects the system as it
takes longer to stabilize but reaches a high constant velocity as shown in number 5.
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Temiloluwa Shokunbi
Cruise Control Lab 1
→ Explain any trends observed in the car's velocity for the different parameter values when
subjected to the same step input u.
When the car is subjected to different parameter values with the same step input u of 500 N, the
car approaches a constant velocity of 20m/s after 100 seconds in number 5. Next, the car reaches
a constant velocity of 3.5m/s after 7-8 seconds in the first graph of number 6. After, the car
reaches a constant velocity of 2.8 m/s after 4 seconds in the second graph of number 6. The
system will reach a constant velocity with the same step unit function as well as have stability.
MATHLAB CODE:
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