My initial results with new Tow Mode

azbill · Oct 18, 2023

Took out my horse trailer today to try it out. It is a dual axle slant and the empty weight is 3200lbs

Rivian R1T R1S My initial results with new Tow Mode HorseTrailer

Once I hooked up the trailer the Trailer Info shows:

317 miles at 100% (but the truck was actually at 84%)
Trailer weight 0lbs
Towing efficiency 0 mi/kwh
Distance towed 0 miles

Started driving and it showed an icon for calculating, after two miles at 45mph it guessed some new numbers.

223 miles at 100%
Trailer weight 3000lbs (close, it claims 500lb tolerance)
Towing efficiency 1.6 mi/kwh
Distance towed 2.3 miles

At that point went onto a highway and essentially drove a total of 50 miles in a loop at 70mph.

The end results, which are still optimistic:

211 miles at 100%
Trailer weight 3500lbs (went up 500lb)
Towing efficiency 1.3 mi/kwh
Distance towed 50.3 miles

The trip meter showed I used 40kwh and got 1.26 mi/kwh. The real full range estimate should be about 150-160 miles, maybe after some more trips it will figure it out.

azbill · Oct 18, 2023

I do have two more trailers to test, one heavier and one lighter with a single axle.

Mathme · Oct 18, 2023

This is good info for us info geeks out there. :clap:

I'll be curious if the "within 500" pounds is more of an increase to the next 500 increment or not. need more data....

azbill · Oct 18, 2023

Mathme said:
This is good info for us info geeks out there.

I'll be curious if the "within 500" pounds is more of an increase to the next 500 increment or not. need more data....

Next time I will load our horse to increase the gross weight by 1000lb to see what the truck thinks.

It increased the weight by 500lb after driving faster, which leads me to believe they are fudging the weight to account for some of the drag.

Dark-Fx · Oct 18, 2023

azbill said:
Next time I will load our horse to increase the gross weight by 1000lb to see what the truck thinks.

It increased the weight by 500lb after driving faster, which leads me to believe they are fudging the weight to account for some of the drag.

It'd be a big miss if they don't have some hidden estimation of the aerodynamic factors. Weight acts way different.

azbill · Oct 18, 2023

Dark-Fx said:
It'd be a big miss if they don't have some hidden estimation of the aerodynamic factors. Weight acts way different.

The Rivian is the only EV I have had that does not seem to adjust the range estimator for current driving conditions. Most cars factor in current consumption and remaining battery to provide an estimate assuming you continue at current conditions.

I was just thinking the other day, I would like to see all EVs provide an option to display miles/%battery efficiency number, in place of miles/kwh. It would make human range estimation much better.

kylealden · Oct 18, 2023

azbill said:
Next time I will load our horse to increase the gross weight by 1000lb to see what the truck thinks.

Great, now we need per-horse profiles...

kylealden · Oct 18, 2023

Dark-Fx said:
It'd be a big miss if they don't have some hidden estimation of the aerodynamic factors. Weight acts way different.

The interview on TFL Truck suggested they do factor in aero. (I'm curious if/how this shows up as weight on the display, but it should be at least coarsely estimable separate from weight by comparing the increasing power requirements at various speeds.)

rodhx · Oct 18, 2023

azbill said:
The Rivian is the only EV I have had that does not seem to adjust the range estimator for current driving conditions. Most cars factor in current consumption and remaining battery to provide an estimate assuming you continue at current conditions.

I was just thinking the other day, I would like to see all EVs provide an option to display miles/%battery efficiency number, in place of miles/kwh. It would make human range estimation much better.

I think it does adjust, or at least it does when you‘re using nav or towing. The nav destination window shows an estimate of range remaining when the destination is reached and that value changes as you drive.

The previous update also adjusted pretty quickly when towing. It did the old “immediately cut range to 50%” when you plugged up the trailer but displayed range increased quickly when pulling my usual small trailer. Earlier software versions were very slow to adjust for a light load so remained unrealistically pessimistic.

Admittedly I pay little attention to the range # displayed when driving, even during our road trip last weekend. When traveling i find the nav “range remaining“ info most useful.

Marchin_MTB · Oct 18, 2023

kylealden said:
The interview on TFL Truck suggested they do factor in aero. (I'm curious if/how this shows up as weight on the display, but it should be at least coarsely estimable separate from weight by comparing the increasing power requirements at various speeds.)

Probably right, fitting a nonlinear equation to measurements of power at a variety of conditions. A little disappointed that they dont display an estimated Cd*A for the trailer.

azbill · Oct 19, 2023

rodhx said:
think it does adjust, or at least it does when you‘re using nav or towing. The nav destination window shows an estimate of range remaining when the destination is reached and that value changes as you drive.

I agree it does do something in the nav, but that number never lines up with the driver display. When I am on a trip, I simply count on 3 miles/% of battery, in good weather conditions. It is very accurate.

HyperionMark · Oct 19, 2023

Heading out with our camper tomorrow. Excited to see how all the new features work out!

hilld · Oct 20, 2023

azbill said:
Next time I will load our horse to increase the gross weight by 1000lb to see what the truck thinks.

It increased the weight by 500lb after driving faster, which leads me to believe they are fudging the weight to account for some of the drag.

Are you going to drive the horse around "for science"?

R1Thor · Oct 20, 2023

Marchin_MTB said:
Probably right, fitting a nonlinear equation to measurements of power at a variety of conditions. A little disappointed that they dont display an estimated Cd*A for the trailer.

I love it when you talk nerd to me :involve:

MoreTrout · Oct 20, 2023

rodhx said:
Admittedly I pay little attention to the range # displayed when driving, even during our road trip last weekend. When traveling i find the nav “range remaining“ info most useful.

I am 100% the opposite. After dozens of long trips, I have found the nav calculated range remaining absolutely useless. It approximates a minimum of 30-60 miles of range remaining less than what I know I will arrive with. And it doesn't adjust/improve with multiple trips on the same route. What's worse, it always calculates an unnecessary stop to charge, and if I remove that stop it won't even list that route as an option, or it will try to tell me I can't make it. If I subtract the known miles to travel from the estimated miles remaining on the driver screen, I'm almost always +/- 5-10 miles.

At least this towing update gives me hope that the NAV will eventually be able to learn and do better, but so far it is next to useless in determining range remaining on any trip I take. The only current "adjusting" on the way is just applying the same bad math it started with, but with fewer miles to go so it becomes a relatively smaller error. I have been doing the same ~200 mile route once or twice a month round trip on the exact same route, and to date the NAV has learned zero about how wrong it is.

My initial results with new Tow Mode

azbill

Well-Known Member

azbill

Well-Known Member

Mathme

Well-Known Member

azbill

Well-Known Member

Dark-Fx

Well-Known Member

azbill

Well-Known Member

kylealden

Well-Known Member

kylealden

Well-Known Member

rodhx

Well-Known Member

Marchin_MTB

Well-Known Member

azbill

Well-Known Member

HyperionMark

Well-Known Member

hilld

Well-Known Member

R1Thor

Well-Known Member

MoreTrout

Well-Known Member

Similar threads