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Not liking one pedal driving

HaveBlue

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What happens when you step on the brake to disengage cruise control? Is it really abrupt?? After all it goes to zero throttle and some braking.
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Pacblue22

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I find tight parking spot, specifically parallel parking, to be an absolute PITA with the Rivian...same with backing out of garages or tight spots. The absolute precision required is a bummer vs. the ICE idle. Its like parallel parking an ICE vehicle on a hill...I am getting better at it, but not a fan.

One pedal on curves or even regular driving is better, IMO, so I guess I am a little polar - love OPD for everything but slow speed/tight maneuvers...

It's been said, but my only issue with OPD is getting in my garage, which has 6" of back/front clearance total. So I have to feather it to just the right place (I use the hanging tennis ball). The comparison to manual transmission is right...with an ICE auto transmission I can let the car creep forward and hit the brake at the right moment. And if I flinch my oopsie is a hard stop. On the Rivian (or a manual ICE) a little flinch and I've done a worse oopsie...
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usulio

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What happens when you step on the brake to disengage cruise control? Is it really abrupt?? After all it goes to zero throttle and some braking.
I think the regen gradually kicks in, giving you a second or two to get back on the accelerator.
 

usulio

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I find tight parking spot, specifically parallel parking, to be an absolute PITA with the Rivian...same with backing out of garages or tight spots. The absolute precision required is a bummer vs. the ICE idle. Its like parallel parking an ICE vehicle on a hill...I am getting better at it, but not a fan.

One pedal on curves or even regular driving is better, IMO, so I guess I am a little polar - love OPD for everything but slow speed/tight maneuvers...
Yeah, also annoying over things like speed bumps in a parking lot. It would be nice if Rivian introduced something like a "chill mode" setting for low-speed and parking scenarios.
 

Pacblue22

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Agree, the throttle mapping for things like that is way off as far as I am concerned. I am strangely even better with a manual transmission than a Rivian is those situations - I guess hill parallel parking with a manual is a always actually tough, but I grew up in San Francisco, so you had to get good fast...lol

But I do think Rivian could do a way better job with it, just not sure you can please all the people all the time...

Yeah, also annoying over things like speed bumps in a parking lot. It would be nice if Rivian introduced something like a "chill mode" setting for low-speed and parking scenarios.
 

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Zoidz

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No, the friction brakes are not applied during manual one pedal driving.

As I said, if one pedal driving by itself did use the friction brakes, Rivian wouldn’t need to provide the on-screen warning and alert sound when full regen isn’t available. Why? Because stopping distances would not increase if the vehicle used friction brakes to make up for loss of regen stopping power when it was unavailable. Seriously, you can prove this to yourself by having a passenger video the pedals while driving with one pedal manual driving so you can see the only time the brake pedal moves is when Hold is activated.

You can engage in constructive discussion and use data to figure out what’s going on or you can be argumentative and dismissive by relying on experience which does NOT apply to a Rivian. You’re more likely to get help if you choose the former.
There are two fairly solid indications that Rivian does automatically blend from regen to friction braking as the vehicle slows.

1. From the Rivian EPA Application for Certification - Read the last sentence:

08.07.03 Overlap of friction brakes and regenerative braking
One pedal driving by default, and in this mode, fully releasing the pedal yields the maximum regen allowable in the level selected. As the driver manually increases primary service brake pressure and friction braking torque, the vehicle regen level will proportionally ramp down to 0 Nm. The ramp profile is affected by many factors, such as those described in 08.07.01. When auto hold is active and the vehicle approaches standstill, the braking torque will blend from motors to friction brakes.

2. It has been documented that Rivian uses the Bosch iBooster braking system for EVs. On the Bosch Web Site, it talks about using friction braking at low speed deceleration, and an animation video specifically explains that blended braking is used as the vehicle comes to a stop. This is illustrated at the 56 second mark in the video.

Rivian R1T R1S Not liking one pedal driving 1696299467388

The inset:
Rivian R1T R1S Not liking one pedal driving 1696299493574
 

Zoidz

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Whatever dude. I've been racing cars a long time. I know what the sound of pads moving fore and aft in a six piston caliper sound like.
Congrats on your car racing history. I have SCCA driving experience and crewed years ago on a sportsman modified. We used Wilwood quick change (no clips/springs, etc.) so pad click was/is considered normal on a race car.

A quick Google search returns thousands of hits/discussions about brake pads moving in the caliper, and all the ones I looked at consider clicks an abnormal condition on street vehicles of all types. No one else has reported this issue on a Rivian and Rivian does not have six piston racing calipers, so the logical conclusion is that you have a defect or it is not the pads.

I replace brake pads several times a year on my family's various street cars, and having been doing this since I was 15, starting with drum brakes and was taught by a professional mechanic friend of the family. The only time I have heard clicks from pad engagement is when I did something wrong, or very infrequently during bedding on the first pedal press.
 

HaveBlue

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I was qualified for the formula Ford race series and drove against Juan Pablo Montoya. He was faster than me but I can hear pads click on vehicles when applying them in reverse. That's how most of my racing is these days.
 

SoCal Rob

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There are two fairly solid indications that Rivian does automatically blend from regen to friction braking as the vehicle slows.

1. From the Rivian EPA Application for Certification - Read the last sentence:

08.07.03 Overlap of friction brakes and regenerative braking
One pedal driving by default, and in this mode, fully releasing the pedal yields the maximum regen allowable in the level selected. As the driver manually increases primary service brake pressure and friction braking torque, the vehicle regen level will proportionally ramp down to 0 Nm. The ramp profile is affected by many factors, such as those described in 08.07.01. When auto hold is active and the vehicle approaches standstill, the braking torque will blend from motors to friction brakes.

2. It has been documented that Rivian uses the Bosch iBooster braking system for EVs. On the Bosch Web Site, it talks about using friction braking at low speed deceleration, and an animation video specifically explains that blended braking is used as the vehicle comes to a stop. This is illustrated at the 56 second mark in the video.

1696299467388.webp

The inset:
1696299493574.webp
Getting back to OPD and whether friction braking is involved in Rivian’s implementation…

In the video you linked, at 1:49 it addresses how the 2 different components which can be attached to the brake pedal, “…detect the driver’s braking request and regulate the torque blending.” This seems to indicate that the blending is used to slow the vehicle when the driver presses the brake pedal and it doesn’t address OPD (where the driver does not press the brake pedal) at all. As Rivian implemented the hardware for OPD, it seems the friction brake must only apply at speeds approaching zero to fully stop and hold, such that there is no practical brake blending to slow the vehicle.

While we don’t know all the details of Rivian’s implementation of OPD yet, we do know that as currently configured, Rivian needs to warn the driver that the vehicle will not slow down as expected when regen isn’t available. I get to experience the lack of regen several times each week and the vehicle does not slow down in any perceptible way using manual OPD when regen is unavailable. Braking is just suddenly absent because the friction brakes don’t appear to be used by manual OPD to slow the vehicle. I assume that ACC, AEB, and other automated safety systems would use the friction brakes to slow the vehicle from something higher than walking speed when I’m coming down a hill, but OPD does not.
edit:typo
 
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Sevn86

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I’m use to my vehicle and I love the OPD and high regen.
 

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mindstormsguy

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You can definitely hear some pads click in some calipers, especially if you’re braking for the first time after changing direction from forward to reverse or vise versa. Just because some people don’t know how to hear certain behaviors of their car, doesn’t mean it doesn’t exist. Most street vehicles have this tuned out as much as possible, because it’s just added NVH. I haven’t actually noticed this on my Rivian, BUT my pads have started to squeak occasionally, so that’s how *I* know that Rivians blend brakes for the last few MPH of slowing with one pedal driving.
 

mindstormsguy

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Maybe should have done some research before jumping in as an EV early adopter. All of them use OPD and regenerative breaking and I doubt any one of them would seriously consider a feature to turn that off completely....self accountability...
Maybe *you* need to do some research. The Taycan, etron, and etron GT (and probably other VAG EVs) allow (and in fact default) to coasting on throttle lift. I know for a fact that the etron uses a Bosch brake by wire system that will use 100% regen using the brake pedal, until the driver requests more braking force than the regen can provide, at which point it will start blending in the friction brakes. It also makes the first brake application of a drive use the friction brakes exclusively, to wipe the rotors, and ensure that the brakes are clean and ready should they be needed.
 

_R1S_

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I'm not going to convert the disciples here, just super annoyed with about every one pedal driving situation in this car. To each his own. And parking is a royal pita. The reality is, rivian is too cheap to adopt blended braking so has done like tesla by speaking the virtues of OPD. It makes for a terrible driving experience where the only solutions are a series of workarounds.
 

Zoidz

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I'm not going to convert the disciples here, just super annoyed with about every one pedal driving situation in this car. To each his own. And parking is a royal pita. The reality is, rivian is too cheap to adopt blended braking so has done like tesla by speaking the virtues of OPD. It makes for a terrible driving experience where the only solutions are a series of workarounds.
Too cheap, or is it strictly a design/operational philosophy to maximize regen as part of their "ethos"? The Bosch system can do blended braking and Rivian has documented they do it at low speed. I'm not sure that there is any added hardware cost, just software, to do blended braking with the Bosch system. There was an article I read a while back that said Rivian uses the exact same hardware as Tesla. I'll see if I can find it.
 

SoCal Rob

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I'm not going to convert the disciples here, just super annoyed with about every one pedal driving situation in this car. To each his own. And parking is a royal pita. The reality is, rivian is too cheap to adopt blended braking so has done like tesla by speaking the virtues of OPD. It makes for a terrible driving experience where the only solutions are a series of workarounds.
I think what you meant to write was, “It makes for a terrible driving experience FOR ME…” because at least some of us do not share your experience.

I’m neither an OPD disciple nor a Rivian fanboy. I expected to HATE the OPD and before getting my Rivian I anticipated all kinds of problems with driving smoothly and parking.

My reality and experience is that I can drive our R1S at least as smoothly, and more easily, than any other car I’ve owned. I’m not an especially coordinated person so I don’t think I have any superior physical skill when it comes to driving. I can drive a manual transmission car so maybe slightly above today’s average driver? All I know is that my mom thinks the way the vehicle comes to a smooth, graceful stop consistently is amazing.

When we took delivery of our R1S I put it in high regen to try the worst case scenario (worst because I expected to hate it) and adapted after a couple stops. To me, the OPD is all about planning ahead, so the only time I need to touch the brake is when something unanticipated happens and I know that OPD regen will not do the trick.
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