You’re assumptions are just over the top. Assume the cat is a sphere. Real world applied engineering does not work like this.
I agree with PaulMLAS. It’s great the Rivian can be flat towed. If it can regen while being towed in a safe and legal manner that is a bonus.
I don’t want an over...
Because that isn’t right. In order for the Rivian regen breaks to be engaged, the RV brakes would have to be engaged also. It is also unlikely that the Rivian would break with only the Regen but I’ll just give you that one. At the absolute very best, the Rivian would account for a quarter to...
I'd be interested to see your math on this and assumptions.
Seems like some of the assumptions have this number significantly higher than real life application.
What is your split between the energy absorbed by RV friction/exhaust brakes, Rivian friction brakes, and Revian regen? From the way...
The one scenario it could be helpful is the following. Note: I believe this is too small a window to be worth it.
If you use regen braking only while the RV is actually braking you are recovering energy that would have otherwise been transferred as heat in the brakes.
If you recover that...
In theory you could have a tow bar that had a three way damper that could trigger brakes in compression, trigger acceleration in tension, and have a middle ground which would be neutral/coast, but that is a significantly more advanced (expensive) version of a surge brake. Even this setup could...
What am I making up?
There is no way that surge brakes are designed to take the anywhere near full force of the towed vehicle prior to applying the brake. That makes no sense.
If there was propulsion from the towed vehicle, it would compress the damper/spring in surge brakes and trigger the...
If a quick release isn't properly seated and locked, bar will get destroyed if you put any compressive load on them. They should not fail even if put under full force of the vehicle, but again that is not what they are designed to have happened on a regular basis. There is a massive difference...
A properly installed ReadyBrake should never hit forces you are stating. The breaks should trigger while the trigger compression is happening and not once it over compresses and slams.
If a brake fails, your bars certainly could fail. They are over engineered, but that isn’t something I’m...
THIS^^^
You guys should take a look at how flat tow bars are constructed. They simply aren't built to handle compression of any form and any hiccup would destroy them in compression. An entirely different system would have to be designed that would have to be significantly more heavy duty by...
Articulated buses are completely different. They are meant for low speed urban environments, and there are studies that show they are inherently less stable because they are pushers.
https://trid.trb.org/view/293829
The articulated pusher buses also have an enormous advantage in their...
I think you are discounting how incredibly complex this is. How this would require real-time data from both the car and the RV, and probably a multiple new sensors. Some of which would have to be on the hitch.
Not sure how this could be done simple, safe, or efficiently.
1. You would run the battery out because you would recapture energy at a slower rate than expended
2. Propulsion wouldn’t work because the application of the force through the single point of the hitch would destabilize the RV...
Great post. Thanks for capturing this in one place and communicated better than I have been able to.
Also, I forgot about the exhaust brakes turning on the brake lights. That makes the complex solution for coast unnecessary. Just brake or no brake.
The key here is “having to” or not. You don’t have to send any additional info to the Rivian other than brake or no brake for everything to work including regen. The one scenario outside of that which we are now talking about is what to do during “coast”. If you want special behaviors during...
No — we are talking about something more advanced beyond just simple flat tow. For simple flat tow all you need is Brake or No Brake input. That is it.
You probably choose wireless connections in 1000 different aspects of you life over wired. Wired is inherently limited and not upgradable. I get what you are saying, but you are assuming you are actually able to diagnose and fix the problem. Most RV drivers would be either unwilling or unable...
Because wireless you can get acceleration, coast and brake inputs instead of just brake vs no brake. It is one less physical connection you have to make between vehicles, and less parts to fail. If the connection does fail, it is significantly easier to replace a wireless component than take...
This is what I would love for them to have. A wireless connection with a simple plug into the RV would be a slam dunk. Not really any additional hardware required on the Rivian depending on how the communication is done and hopefully hidden tow mounts. Put the Rivian in town mode and...