I can’t let it go. There is more here to explore. First, I can’t believe that I looked at braking and then turning but not turning then braking. And what about braking while turning? I will model braking and then turning – but it won’t stop here.

Consider a few motions. I could turn and then brake (which I am looking in this post). Another option would be to brake and then turn. I already showed that this takes a longer distance than just stopping. Braking and then turning in general won’t work. Suppose I brake and slow down to a certain speed. Now I am a certain distance away from the wall going at a certain speed. In that previous post, I showed that it takes less distance to just stop rather than turn.

Turning first might be different. If the car turns a little bit, then there will be a greater distance that it can travel before it hits this really wide wall. So, here is what I am going to do. I will use python to model this motion and calculate the x-distance it takes to stop the car. For the first run, I will just go straight. Then I will turn just a tiny bit and then brake. I will keep increasing the amount the car turns before stopping and record the distance (in the direction of the wall).

Here is the data:

First, a quick check. Does this data agree with my previous data? Using these same parameters (initial speed and coefficient of friction) I get the same stopping distance for no turn and 90 degree turn. So that is good.

I am not surprised that stopping without turning is still the shortest distance. But, I am surprised that turning 90 degrees is not the largest stopping distance. From the above data, it looks like the worse thing to do is to turn about 60 degrees and then stop. Whatever you do, don’t do that.

One more thing – there is more to do. I have looked at:

- Braking
- Turning
- Braking then turning
- Turning then braking

But this is not every possibility. Is it possible you could turn right then left then brake? Maybe. There is a way to deal with these more generic functions – but I am not going to deal with this now.