BRC 1966 - Gentleman Brobots Club [RACE 7 P&Q]

How much did you pay the German Norman?

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I can only say that the program itself is unchanged since race 2 or 3. I did a few tests and in not a single one he had a somewhat similar performance/similar luck with so many crashes around him. So basically this must have been the compensation for all the bad luck in the past and it all just came together perfectly.

I really enjoyed the race although I thought I could achieve a podium finish or even a victory with all the crashes. But two driver errors made me stuck in traffic for more than half of the race. With that kn mind I am happy with the 4th position.

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Being stuck in traffic is a much bigger problem than I anticipated it to be. I have a mediocre 0-100 km/h car and that has cost me a few positions in several races. Makes everything even more intense :slight_smile:

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@Der_Bayer , is the fuel consumption only based on enginespeed, or is it based on the current vehiclespeed and drag?:nerd:
Because Pyrlix seemed to use a lot of fuel in this race, considering he was being dragged around the track for a large portion of the race. :grin:

It’s based on throttle position, power@current RPM and BSFC@current RPM. So it makes sense that he used more than he would have used while driving alone. He was higher up in the rev range for a longer time than normally.

If you are close enough behind a larger vehicle the drag can be reduced by up to 90%,
i don’t know how much it might be with same size cars.
Would this be difficult to program?

The drag might be reduced, but what matters when it comes to fuel usage is the engine, and more specifically how many revs it’s running at.

You often hear people say that lower drag helps cars use less fuel, but that is only true when you keep a constant speed. For example, an engine needs 50 hp to pull a volvo wagon at 100 kph, but only 40 hp would be needed to pull a Prius at that speed, therefore using less energy.
In racing, the car behind still is using the full available power, and a bit more, in the quest of finding some extra speed, since the forces against movement are lower when in a slipstream. So the racing driver would still use the same power, but his Volvo wagon would suddenly be as slippery as a Prius, giving some extra kph for the same power and fuel use.

(belatedly)

SECOND PLACE! Second place! Packbat Auto Works is back in contention for the top three overall! :smile:

Absolutely. Not considering how well the car could weave through traffic cost me dearly in my first three BROBOT competitions; this is the first time I brought a car with the straight-line speed to overtake reliably.

Sorry Matti! It looks like my car’s no good piling into corners at high speed, seeing as the only track it did particularly well in was Brands Hatch…

Could have been some good points in the bag, too!

Woh! I finished 33rd! And I decided not to watch this race… typical! :blush:

If you use FULL power 5-10 meters behind another car, the result is a crash.
Drag is the biggest reason for higher power needed to keep a certain speed.


Look at the second point under “Drafting”
“Auto racing drivers also draft in order to conserve fuel, the better to gain
competitive advantage by reducing the frequency of fuel stops or, more
often, to reach a higher speed before pulling out to attempt to overtake
another driver.”

Yes, but that isn’t how the Brc works. The drivers are always going flat out, trying to overtake. In that case, pyrlix’ car was trying its hardest to go through, but simply wasn’t fast enough to accomplish that. My point is valid, it was using the same amount of fuel or more than on normal driving.

Also, no need for condescending replies, okay? :wink:

That is why i asked Der_Bayer if his program was only using drafting for higher speed,
or if it also used it for less fuel.

The drag might be reduced, but what matters when it comes to fuel usage
is the engine, and more specifically how many revs it’s running at.

True in this sim, but not IRL. Trottle position+rpm is both involved in how much fuel is used.
Why else would a EFI engine need a TPS?
I’m not a programmer, so i don’t know how much work would be involved in adding realworld physics into the simulation.

What exactly do you think is missing in the simulation? The driver goes full throttle, I give him full throttle performance. If he is in the slipstream, drag is reduced.

Actually, dumb question: how does BROBOT model being held up by the car ahead? For driver errors and such, having the car instantaneously slowed is probably a good enough approximation, but for being unable to pass, it might make sense to drop the throttle input briefly to represent the driver backing out - which might slightly reduce the fuel consumption.

Exactly what i tried to ask, but since english is my second language,
i was prehaps not as clear as needed in my posts. :pensive:

Being held up is only possible in corners, when the car is close to its maximum cornering speed anyway (else it would just drive around the other car). So the driver is not stepping on the gas a lot anyway. If I remember correctly, I just drop the speed by a small bit. Playing around with throttle input did not give good results, because the cars are so different over the years and compared to each other. I wanted to have a robust solution without the need for major tweaking each season :wink: It’s not physically correct, but it works. A bit of fuel should still be saved, being at lower RPM/power while in the corner than normally.

##[color=#3070dd]Donington P&Q Results[/color]

Here are the practice and qualifying results of the last season event in Donington:

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Still processing for me. :frowning2:

The last one. I hope the season goes out with a bang for more people than just Vikus. Something truly spectacular. Or crazy. Or both.