Acceleration/Braking Event

[TG]

Alright, on the Rule Changes to Mix Things Up thread, there was interest in incorperating a brake test of some sort into competition. I've gone through the thread and here are the ideas so far:

- A measured braking distance after the acceleration run

- Accelerating and braking between two pilons with very narrow, controlled speed areas around the pilons

- I'll add to the list something like a 0-(x speed)-0 with a radar gun or daq and large display in drivers sight

The points would have to come from somewhere, maybe 50 from the endurance event.

The only disadvantage to this would be some flat spots on the tires if they lock (which they must be able to).

I'll let others chime in on what they think of something like this.

[TG]

Alright, on the Rule Changes to Mix Things Up thread, there was interest in incorperating a brake test of some sort into competition. I've gone through the thread and here are the ideas so far:

- A measured braking distance after the acceleration run

- Accelerating and braking between two pilons with very narrow, controlled speed areas around the pilons

- I'll add to the list something like a 0-(x speed)-0 with a radar gun or daq and large display in drivers sight

The points would have to come from somewhere, maybe 50 from the endurance event.

The only disadvantage to this would be some flat spots on the tires if they lock (which they must be able to).

I'll let others chime in on what they think of something like this.

[adrial]

I think accelerating from 0 -(x speed)-0 would work well.

Driver launches, accelerates through the standard acceleration distance then gets hard on the brakes.

Radar would be used to track the braking of the car. A minimum speed is picked such that all cars are capable of it, and braking distance is calculated from that speed to zero.

However, the biggest issue with this is variations in the parking lot. Lets say braking from 40mph to 0 is chosen for the test. Car A accelerates to 60mph and starts braking, it will be on different pavement during its 40-0 stop than a car that accelerated only to 40. I am not sure how big an issue this would be, depends on where they setup the event...if there is a large bump towards the end of the braking zone...etc.

[Kamil S]

I think it should go 0 - 40? - 0, and they should time the whole run and the seperate 0 - 40 and 40 - 0 runs, and take distances covered.

This makes sure that the drivers need to be aware of their speed at all times, and hopefully teaches some good downshifting techniques!

[Kevin Hayward]

Accelerating to a set speed is going to be difficult for these cars. Most vehicles do not have a speedo. Even if they did how could you ensure callibration. A lot of cars have the wheelspeed sensors necessary.

However it is likely that this sort of event will increase the cost and complexity for most if not all teams.

How about a different method of requiring teams to make space to strap on a packaged g-sensor. These could be provided by the competition and strapped on near the start line and taken off after the runs are completed. That way you would not need one for every car. The score could be calculated based on highest maintained g-force or something during braking. Maybe pick any speed and take the average of the negative g's. Something like this shouldn't be too hard to implement and may reduce the driver requirement.

There are some pretty good g-sensor packages about used for karts etc that should make this relatively painless.

However I do wonder about how you would be able to add an extra event to the US comp without extending the overall length of the competition or reducing the number of teams. It is run very well and there does not seem to be a lot of free time.

Cheers,

Kev

[Nick McNaughton]

I'm a big fan of this - a simple go-to-whoa would be my choice. Start at this line, drive over there and stop with some part of the car between those two cones as quick as you can.

It could even be done by breaking a beam at the start and finish, with the non-disqualification requirement that the car stops across a line drawn between two cones, so long as the line is contained by the vehicle wheelbase - the front wheels have crossed it, and the rears haven't. And crossing it sideways doesn't count either. No speed measurement or G sensors needed...

It's a pretty harsh test of driver skill, vehicle setup, acceleration and braking capability, and requires the same equipment as the acceleration event. I think it'd be a great addition to the comp...

Cheers,
Nick

[Charlie]

Nick maybe I'm missing something but you make it sound way too easy.

I would love to see a braking competition, but how do you accomplish it?

In your explanation of the event, how fast are the cars going before they brake? That is the problem.

I see it the same as Kevin. It's be fantastic, but incredibly difficult to do properly and fairly. If you've seen or competed in the Road and Track competition, you've seen what I mean.

If you rely on a signal from officials that you've reached a certain speed, you are relying on at least the driver's reaction time, and possibly someone else on the sidelines. The fix for this would be a system that automatically senses speed and tells the driver when they've reached it. This would also be better because the driver could practice with it. But, not everyone can afford this and it shouldn't be mandatory, so its a monetary advantage.

A setup to accel and then brake puts better accelerating cars at a disadvantage, and how do you score it?

Like I said Nick you make it sound simple, and I'd love it to be, so if you have solutions to my problems you'd definitely have a great competition addition on your hands.

[Dan G]

Sounds exactly like a Gran Turismo license test. I agree, running a braking test would be difficult. It'd be much easier to run a go-woah with the required stopping area. Get there as fast as possible, must come to a full stop within the cones. Although I'm not sure it'd be easy to get electronic times. It could just be a simple light beam for the start/finish as long as the car stops within the specified area.

But you'd have to give the driver's 2-3 shots at it each. Cause they'd definiely slam the brakes too early or too late one of those times. Prepared teams would be allowed to measure off a "brake here" flag from the finish line, then let the driver adjust as needed.

This event *could* replace the acceleration event, as that would be a huge portion of the time/points. But that would probably draw a lot of complaints.

[Eddie Martin]

When measuring long. and lat. g in the skid pan and acceleration events, time between beams is used because it is the only really practical solution for such a large competition so a similar simple approach would need to be used for this test.

So i have to agree with Nick that it be run as a go-to-whoa eg. the vehicle has to get from point a to point b and stop as fast as possible. (similar to some of the license tests in gran turismo) (Dan, You got your post in while i was typing ) I still can't work out how you would stop the clock accurately when the vehicle has stopped.

If you did try to get cars up to a certain speed and then brake, I can't see how you would accurately police the exact speed you need to brake from and whether you could get 200 + drivers to do it in a day. If you are traveling any faster or slower than the set speed it would be an advantage or disadvantage depending on whether you are over or under the speed.

It would also be a nightmare for the organisers, logistically. Add to this the fact that most teams are making full use of the current events to mandate extra tests.

[Denny Trimble]

I agree with Charlie, telling the driver he's reached a high enough speed was a difficult thing in the Road and Track Challenge when we did it in '03. They had a big display hooked up to a radar gun, but it only updated at about 1Hz! Apparently they said it would "blink" when it sensed 60mph, but our driver saw 48, 58, 68, then hit the brakes

Requiring all cars to reach a minimum speed would be difficult, I saw several cars run the accel event at about 25mph.

I like the "go and stop over this distance in the minimum time" idea. The start could be just like the accel event (light beam with a short staging distance). The finish could be a light beam, followed by a "DNF" beam two car lengths (or so) away. So, if the car triggers the stop light but not the DNF light, they get a time. If they continue and trigger the DNF light, no good. I guess there doesn't even need to be a light beam for the DNF; there could be a "cone on a string" like in the skidpad event, in the path of the car until it stops, then removed to let the car get off the track.

The "no spinning" rule would have to be enforced by judges; perhaps "both front tires must cross the line before any rear tire" would be a good rule of thumb.