Quite the FUD in your title. Lots of his complaints are either things Rivian can improve in the software, or the hummer will have the same issues if not worse. Some of his complaints are just due to the differences between an EV and an ICE vehicle. You don't get much feedback on how hard you are pushing the throttle like you do in an ICE. Just takes getting used to.
-
Hummer EV Order Tracker: Add Yours Here!
Doug DeMuro has complaints about the Rivian off road...
Interesting take, seems the Hummer is going to win in some of these situations...
1 - 11 of 11 Posts
No the Rivian doesn't have Hill assent or decent control like many modern vehicles or off-Road vehicles have now.Quite the FUD in your title. Lots of his complaints are either things Rivian can improve in the software, or the hummer will have the same issues if not worse. Some of his complaints are just due to the differences between an EV and an ICE vehicle. You don't get much feedback on how hard you are pushing the throttle like you do in an ICE. Just takes getting used to.
FUD, Fear, Uncertainty, and Doubt? Where do you see that? Doug did indeed have complaints with the Rivian off road, and it seems Doug's complaints are all centered around features the HummerEv has. Interesting that he teased the HummerEv in the intro, suppose the 2 are connected? My title was 100% factual, and I did not make any statement about the Rivian's capabilities or lack there of, and therefore not in the slightest FUD. FUD would be to say the Rivian has had several suspension failures in testing both for Motortrend, and at the Rebell Rally, and commenting about the suspension being too weak for the overweight vehicle... That's FUD, but even that is supported with data.Quite the FUD in your title. Lots of his complaints are either things Rivian can improve in the software, or the hummer will have the same issues if not worse. Some of his complaints are just due to the differences between an EV and an ICE vehicle. You don't get much feedback on how hard you are pushing the throttle like you do in an ICE. Just takes getting used to.
Rivian can certainly make their truck better, but for now, it is lacking in key areas for off roaders, and missing features the competition has today. The Rivian on the loose material in Doug's video seems to have excessive wheelspin at times, something off roaders never want, wheel spin on sharp rocks leads to massive tire damage. Old fashioned lockers will eliminate that, it seems Rivian's traction control is not very good for balancing the torque off roading, and needs more work on calibrations. This is tough with electric drivetrains, because the difference is not small as the traction slips away on one wheel, and another wheel has massive resistance, the traction control has to react fast and in a big way, this is tough and can create other unintended consequences in the drivetrain, which Rivian has likely encountered in their testing. I originally thought the 4 motor system would be superior, but it seems not in all conditions, and in certain conditions old school lockers are superior.
I look forward to your similarly titled Doug's off-road review of the Hummer EV.FUD, Fear, Uncertainty, and Doubt? Where do you see that? Doug did indeed have complaints with the Rivian off road, and it seems Doug's complaints are all centered around features the HummerEv has. Interesting that he teased the HummerEv in the intro, suppose the 2 are connected? My title was 100% factual, and I did not make any statement about the Rivian's capabilities or lack there of, and therefore not in the slightest FUD. FUD would be to say the Rivian has had several suspension failures in testing both for Motortrend, and at the Rebell Rally, and commenting about the suspension being too weak for the overweight vehicle... That's FUD, but even that is supported with data.
Rivian can certainly make their truck better, but for now, it is lacking in key areas for off roaders, and missing features the competition has today. The Rivian on the loose material in Doug's video seems to have excessive wheelspin at times, something off roaders never want, wheel spin on sharp rocks leads to massive tire damage. Old fashioned lockers will eliminate that, it seems Rivian's traction control is not very good for balancing the torque off roading, and needs more work on calibrations. This is tough with electric drivetrains, because the difference is not small as the traction slips away on one wheel, and another wheel has massive resistance, the traction control has to react fast and in a big way, this is tough and can create other unintended consequences in the drivetrain, which Rivian has likely encountered in their testing. I originally thought the 4 motor system would be superior, but it seems not in all conditions, and in certain conditions old school lockers are superior.
Rivian definitely has some form of hill descent control. I've read that it doesn't work well if the battery is too full and it probably doesn't work well at the incredibly low speed that Doug was traveling down the hill. It might be an option that you have to enable, maybe he wasn't aware of it if that's the case.
RJ posted a video of the R1T back in February that shows the wheels coming off the ground during a descent and actually turning backwards for a very brief period. That wouldn't happen without Regen being active.
Me too, I cannot wait for Doug to review the HummerEV, it will be interesting to see how he likes it. I think if Doug takes the Hummer EV to that same trail, you will hear a much more positive off roading review for several reasons.I look forward to your similarly titled Doug's off-road review of the Hummer EV.
The Hummer has a front locker, and uses the brakes, and motor control for traction control. (much better control of wheelspin)
Hummer has Hill Decent control, and off road 1 pedal driving, you let off the throttle and the Hummer stops instantly while off roading (up hill or down hill). GM has perfected this system and puts it on the ICE trucks now too.
Hummer has 4 wheel steering which can help in many ways on the trail, and on the road or in parking lots.
Hummer has off road cruise control, so you set it going up the trail, and it will work to control the vehicle speed for the driver. (I have used this feature in range rovers, its cool)
Hummer has larger, more grippy tires, therefore able to drive over larger obstacles. Hummer can also be upsized to 37" tires without modifications, Rivian is maxed out at 33's.
Hummer has tire pressure monitors inside, and when airing down for off roading, you can set the target pressure, and it will honk the horn when you reach the pressure, so you do not need to keep checking with a gauge. (real off roaders would have a gauge anyway)
Inside instrumentation in the Hummer provides more data for the driver, for example roll, pitch, and even a drift meter with memory, so you can see how sideways you got the Hummer.
You sound like a bit of Rivian defender. Having trouble taking some mild criticism? Overall I think the Rivian is good, but the R1T, does not work for my needs, I do have an R1S on order. I think all EV's and manufacturers should be looked at with the same mix of optimism, and criticism, none are perfect.I look forward to your similarly titled Doug's off-road review of the Hummer EV.
Rivian definitely has some form of hill descent control. I've read that it doesn't work well if the battery is too full and it probably doesn't work well at the incredibly low speed that Doug was traveling down the hill. It might be an option that you have to enable, maybe he wasn't aware of it if that's the case.
RJ posted a video of the R1T back in February that shows the wheels coming off the ground during a descent and actually turning backwards for a very brief period. That wouldn't happen without Regen being active.
It has one pedal driving which should provide that feature, the fact that he mentioned using the brake, tells me he turned that off. My Bolt and my Mach E hold the vehicle on a hill without applying brakes, when one pedal is engaged. They simply apply some torque to the motor.No the Rivian doesn't have Hill assent or decent control like many modern vehicles or off-Road vehicles have now.
Bill, you are not taking your Bolt or Mach E on steep downgrades off roading, the Hummer, and all of GM's new trucks use the friction brakes in these technical off roading situations because the motors cannot instantly control technical rock crawling using re-gen. Re gen cannot lock the vehicle, hence why EV's when they get close to a stop, they engage the friction brakes. Some Ev's are better than others at this. Stop sign hold is accomplished by friction brakes, not motor torque.It has one pedal driving which should provide that feature, the fact that he mentioned using the brake, tells me he turned that off. My Bolt and my Mach E hold the vehicle on a hill without applying brakes, when one pedal is engaged. They simply apply some torque to the motor.
Some people have actually measured brake pressure on the Mach E using torque pro and found it is not applying the brakes, even when holding on a hill. It is not regen, it is application of battery power to the motor to hold the vehicle. I agree the slopes that I have stopped on are not as steep as off road. The Mach E has an auto hold feature, and you can feel the brake application in that mode, but it also has a time delay.Bill, you are not taking your Bolt or Mach E on steep downgrades off roading, the Hummer, and all of GM's new trucks use the friction brakes in these technical off roading situations because the motors cannot instantly control technical rock crawling using re-gen. Re gen cannot lock the vehicle, hence why EV's when they get close to a stop, they engage the friction brakes. Some Ev's are better than others at this. Stop sign hold is accomplished by friction brakes, not motor torque.
Since the Hummer only has one front motor and one wheel can be off the ground, it will need to use some brake as well. Although with a E-locker that may not be needed either.
I used to design electric servo control loops for aircraft and it is easy to apply torque to stop the motor from back driving. Regen occurs using the back electromagnetic force (commonly referred to as BEMF) when the motor is moving but no current is being supplied from the control loop (coasting to a stop). Once the motor stops coasting there is no more regen, but the control loop can lock the position of the motor.
Hummer uses friction brakes for off road one pedal driving, the software and actuators are lifted right out of the Silverado ZR2, and Sierra AT4X programs. When you are rock crawling, the sudden changes in acceleration and deceleration could not be modulated with motor re-gen without overworking the inverter (motor controller). For the same reason the 4 motor system in the Rivian is not as good as real lockers in many off road situations,Some people have actually measured brake pressure on the Mach E using torque pro and found it is not applying the brakes, even when holding on a hill. It is not regen, it is application of battery power to the motor to hold the vehicle. I agree the slopes that I have stopped on are not as steep as off road. The Mach E has an auto hold feature, and you can feel the brake application in that mode, but it also has a time delay.
Since the Hummer only has one front motor and one wheel can be off the ground, it will need to use some brake as well. Although with a E-locker that may not be needed either.
I used to design electric servo control loops for aircraft and it is easy to apply torque to stop the motor from back driving. Regen occurs using the back electromagnetic force (commonly referred to as BEMF) when the motor is moving but no current is being supplied from the control loop (coasting to a stop). Once the motor stops coasting there is no more regen, but the control loop can lock the position of the motor.
Just watch the Hummer test drive videos over the rock snd listen to the engineers, it's obvious this is friction brakes near exclusively.
1 - 11 of 11 Posts
- This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
GMC HUMMER EV Forum | HummerChat.com
All The Latest GMC HUMMER EV News, Reviews, Pricing, Pictures, Specs & More on The First Ever Electric Pickup From General Motors.
Full Forum Listing
Recommended Communities
