November Rain
Single Mother
- Joined
- Sep 27, 2005
- Messages
- 13,322
- Reaction score
- 2
- Points
- 31
I think you are looking at a very basic means of speed restriction here, probably via a overdamped control system...If they make cars that only reach 80mph (max), then you're going to have a lot of people flooring their cars. And that's not just to reach 80mph. That also means it's going to ruin your car's acceleration. If 80mph is the speed you reach while flooring the gas pedal, imagine how tough it'll be just to reach 65. The limits in some states are 70 or 75mph. You can't maintain 75mph on a 80mph (max) car for very long without doing harm to your car.

take a look at this graph
consider 1 to be the max speed input of the car. the red, blue and green lines are the response time of the car to get to that max speed(for instance).
the red and green line never actually exceed this maximum value and especially the red line finds it particularly difficult to reach this max value.
the blue line however shows a system of control that allows for a overshoot and the system then calms down and oscillates until the dampner takes effect on the maximum value, thus allowing the car to accelerate and perform quick manouvres but over long periods of time, it will then decellarate and stay steady on the maximum value
this also shows how the functions of a car can be controlled without potentially changing the design characteristics of the vehicle' performance.
obviously the oscillatory response is not necessarily an ideal one but a system could easily be designed where a large acceleration output could be employed and then from there, some natural damping decay to a steady max speed.
if you want further illustration, i could draw it on the relevant curve for you.