Accelerate and brake

[Doug_G]

Wouldn't want to be staring at the kW gauge because there's no telling what you'd crash into.

Probably a power pole...

In all seriousness, though, I think it's way more important to be able to feel whether your vehicle is accelerating, decelerating, or neutral. Particularly, you want to be able to feel whether your roadster is resting on all four wheels, balanced, rather than leaning to the front or rear. It seems like it doesn't really matter whether the battery is actually feeding power or if there is literally no current flowing - the key is the force on the wheels.

Totally agree.

 

[Ladman23]

I have only had my car since Monday, but it seems like people behind me in traffic don't realize i'm slowing down when using regen. Does the brake light come on when you let off the acelerator without hitting the brake? Has Tesla thought about that idea? It worries me that other cars come up quickly behind me if my brake lights are not on and I'm slowing down quickly.

 

[Doug_G]

I have only had my car since Monday, but it seems like people behind me in traffic don't realize i'm slowing down when using regen. Does the brake light come on when you let off the acelerator without hitting the brake? Has Tesla thought about that idea? It worries me that other cars come up quickly behind me if my brake lights are not on and I'm slowing down quickly.

Yes it does. It triggers at a certain deceleration rate (or something along those lines), and immediately if you lift off quickly.

If your car is light colored, you can see the reflection of the "cyclops" brake light in the rear view mirror at night. You might want to take the car out and observe how it works.

 

[Dragon]

The european Roadster doesn't turn on the brake light in this case. It's almost useless to warn the behind by tapping the brakes if he is near you, because you will have already slowed down and with hitting the brake you'll often slow down more than you wished. I've noticed some people had to brake harder because they were surprised by me slowing down. All I can do is to have faith in the driver behind me. It's a problem.

Regarding to the topic: The first days I went with the GoKart-style. I felt more secure doing that. Now that I know the car better I switched to the Right-Foot-only-style.

 

[Mycroft]

Unless you plan on driving automatics the rest of your life, then the safest strategy is to use the right foot only. When you have to do a panic stop, you won't have time to ponder which style of car you're driving. Your foot will immediately go to a pedal and it might be a clutch pedal it hits instead of a brake. Even worse would be that your brain gets crossed and your right foot slams on the gas.

 

[Dragon]

With an automatic car it happened that I wanted to press the clutch and hit the brake instead. Only on low speeds, so no issue.
I think the human brain is really fast at "switching" such things. A few days with the Roadster and now I feel like I've driven nothing else for my whole life.

 

[doug]

Tesla Roadster Wins ReFuel EV Races, We Interview The Driver, Joe Nuxoll

on the track [throttle lift regen is] like having extra rearward brake bias, which isn't always a good thing for balance.
So, to work around the system, Nuxoll employed a highly non-standard method: entering the corners with the throttle still nearly pegged, using his left foot on the brakes. Because the Roadster doesn't need to shift, he didn't have to worry about heel-and-toeing his way into the corners. Instead, he was manipulating the car's computer into staying out of regenerative braking to keep the car balanced.

 

[rabar10]

Devil's advocate question: if the motor's forward torque isn't automatically interrupted under hard braking, couldn't you run into the same issues as the Toyotas a while back? (i.e. right pedal stuck or some other acceleration glitch, trying to fight it with the brakes)

 

[Lloyd]

You can always turn the key off.

 

[Doug_G]

Devil's advocate question: if the motor's forward torque isn't automatically interrupted under hard braking, couldn't you run into the same issues as the Toyotas a while back? (i.e. right pedal stuck or some other acceleration glitch, trying to fight it with the brakes)

No, the exact opposite, I think. He was using the throttle/brake interlock to prevent the motor from getting any power.

Cornering on a race track is somewhat technical. Obviously you want to be traveling between the curves as fast as possible, which means you're always approaching the curve far too fast. You need to brake on a straight line, which maximizes available braking force while shifting the weight to the front thus increasing the tire contact. Next you release the brake and steer into the curve while holding the throttle neutral to maximize available turning force. Then as you unwind the steering you start accelerating again. This allows you to brake at the latest possible moment, achieve the speed you want to take through the turn, and keep your tires inside the friction force limit at all times. This (plus the optimal choice of path through the curve) means you take the turn as fast as possible.

The Roadster's regen gets in the way of doing all this. You have to get off the brake and very quickly over to the accelerator to hold it neutral, so that the regen doesn't alter the balance of the car. I suppose you could heel-and-toe it, but since you don't have a clutch two-footing it is much better. His technique appears to be an extra two-foot trick, where you use the throttle/brake interlock to prevent regen from happening at all. Kinda clever, actually.