opendbc
opendbc copied to clipboard
commaai
GM: Very slow acceleration when resuming from a stop or slow roll
Describe the bug
Very slow acceleration when resuming from a stop or after slowing to a near stop for a lead car to turn; it does get normal at around 30 mph.
What hardware does this issue affect?
comma two
Which car does this affect?
GMC Acadia 2018
Provide a route where the issue occurs
e38a02cae1ef1e0c|2022-04-15--07-43-35--3
openpilot version
Master 0.8.14 @ 1fa1c44
Additional info
This has been an ongoing issue from the beginning for the GM port.
@Twilsonco has fixed this in his fork and has even added a toggle for Normal/Sport/Eco/Creep acceleration modes.
This is due to MAX_GAS (and it's corresponding value in panda) in selfdrive/car/gm/values being set too low. The max value for the gm gas command is 4095, which is what I use for max gas in my fork. The actual acceleration is then limited by the acceleration limits in OP. I think 4095 is excessive if you don't have a "sport acceleration" mode, but a higher value such as 3584 (half-way from the current value to the max) will allow for more reasonable acceleration (still less than stock ACC is capable of).
Here is another route where the lead pulls away and the vehicle has very slow acceleration when resuming.
e38a02cae1ef1e0c|2022-07-10--16-41-43--4
Here is another route where the lead pulls away and the vehicle has very slow acceleration when resuming.
df51b2195de66a9b|2022-10-16--15-55-34--13 @ 16:08:44-13
Here is a example on a new route at 0:07:34 – 5 on Comma Master at 5b9f2c3
df51b2195de66a9b|2023-02-08--10-02-10--5
@Verylukyguy if you can rally the other ICE GMs to gather routes from a stop, that will help us raise the ICE gas/regen limit across the board.
Comma 3, silverado here. Same issue. Excessively slow take up acceleration until about 30ish. Usually have to manually override.
Here is a stock ACC route in Dashcam Mode: df51b2195de66a9b|2023-08-08--16-37-24--9 At this point in the route, my lead turns off and I experience the fastest acceleration in the route. I let the stock ACC do most of the acceleration on this entire route.
@1454 please provide a route with openpilot toggled off in the Device settings, and have the car come from a stop to at least 30 mph on flat ground. This will help us standardize a solution for all platforms!
stock acc route with come to a stop and start from standing still fe80a4e1cedec853|2023-08-08--18-10-55--12
Here is another stock ACC route with a few examples of accelerations from a stop, I think that the best one is here: df51b2195de66a9b|2023-08-11--17-19-41--7 It was a resume from 0 to 50 mph, there are a few before and after it.
I have completed a 4-30+, and 0-27 drives. Traffic slowed up on the second one before I hit 30.
61c6258cac78af08|2023-08-13--13-07-56--0
Referencing Shane's newest discovery: https://github.com/commaai/opendbc/pull/951
I am still experiencing this issue, this did not resolve it.
Can you share a recent route on current openpilot?
As noted in that PR, it does not change any behavior. We still have to change the max value dependant on the car.
A recent route is a good idea.
As noted in that PR, it does not change any behavior. We still have to change the max value dependant on the car.
Ah, I knew the signal-width issue was sorted, but I missed that we weren't making use of the additional width yet.
@Verylukyguy We still do need routes demonstrating the issue as it stands.
As noted in that PR, it does not change any behavior. We still have to change the max value dependant on the car.
Ah, I knew the signal-width issue was sorted, but I missed that we weren't making use of the additional width yet.
@Verylukyguy We still do need routes demonstrating the issue as it stands.
this is still happening for GM across the board, but as far as I know, more prominent on larger the vehicle as limits are currently set from smaller vehicles like the bolt. To fully implement fixes, FPv3 needs to be done first so we can identify the correct torque controller scaling from tire size, weight etc.
@jyoung8607 and @sshane I will be happy to provide all of the routes that I can to help resolve this.
My factory GM Full-Stop-and-Go ACC is not shy about accelerating and will be on and off of the accelerator and brake to keep a constant distance.
OpenPilot is lazy to resume from a start and accelerates slowly up to about 35 MPH before it starts to feel normal.
OpenPilot's braking is also late and harsh, which is uncomfortable and causes interventions and disengagements, but this must be a obviously separate issue.
This has, for the most part, been my experience. Even the changes mochi made helped some, but 0-35 is still pretty slow. Enough so that semis will drive away from me from a red light until after 35 when it starts catching back up.
@sshane There are three resumes from a stop in this route df51b2195de66a9b/00000005--739b7b6c5a/0
- df51b2195de66a9b/00000005--739b7b6c5a/2
- df51b2195de66a9b/00000005--739b7b6c5a/5
- df51b2195de66a9b/00000005--739b7b6c5a/6
This route has a few more: df51b2195de66a9b/00000006--adf3ed521d/0