I made a transparent CAN bus bridge with logging, requesting input

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Open sourcing: no, selling in a few specific varieties: yes. The leaf-specific stuff we've made is a bit too dangerous to mess with in some respects, unless we start documenting publically exactly how you can **** stuff up. That takes time, so I don't think that will happen soon, but eventually there will be an open source leaf-specific firmware I imagine.
 
mux said:
Open sourcing: no, selling in a few specific varieties: yes. The leaf-specific stuff we've made is a bit too dangerous to mess with in some respects, unless we start documenting publically exactly how you can **** stuff up. That takes time, so I don't think that will happen soon, but eventually there will be an open source leaf-specific firmware I imagine.

Do you see this as being 50/50 labor cost and safety risk, or perhaps 80/20? Developing niche software is always expensive, particularly when the hardware to go along with it is also niche, and managing the expectations of OSS consumers as to maintenance and portability is also a challenge. There are similar projects, e.g. http://www.openecu.org/ or https://rusefi.com/ or even https://github.com/commaai/openpilot (which steers the car!). The labor cost difficulty with OSS projects is that they tend to cannibalize non-free businesses, even those that played a founding role, and then the creators can be left without income.

As for safety, open-source licenses usually make it clear that everything is shared as-is with no warranty or guarantee of merchantability and that the developer holds no liability for its use. Real courts obviously may have their own opinions, but licenses have generally held up.

A car isn't really a utility like a web browser or a text editor or operating system. They're more of a luxury, and a complicated one at that! If you already own a car, and you want to modify it without working yourself, maybe you should be able to afford to pay someone to handle the complexity and cost of reverse-engineering. For a computing analogue, look to the Nouveau/NVIDIA driver battle: if you want to use CUDA with your fancy, expensive NVIDIA card, the incentives just aren't in place for that software to be free. CUDA ends up only being available in the proprietary NVIDIA binary blob, and Nouveau (the OSS driver) is basically a minimum viable prototype.
 
This is mostly an ethical consideration, as it's cheap and effective to open source a badly maintained and tested but functional codebase. The fundamental idea behind the code is very simple anyway - just replace some bytes here and there in CAN messages, as long as you know which bytes and which messages, you can just... do it.

However, there will be some expectation of safety and reliability coming from a company converting hundreds of cars on this codebase. It is quite rare for a fork or derivative project to actually change that much or to actively retrofit fixes in the code down the line. Anything I publish now or in the near future that ends up having an obscure failure mode will likely live on in the field and cause some issues down the line. For my own company, that risk boils down to at most the number of cars modified up to that point. For an open source project, that may suddenly become hundreds or thousands of projects spanning many countries, languages and degrees of calamity.

I'm essentially multiplying my support workload (if I want to be able to sleep at night) without much in the way of compensation for me. I'm very aware of the fact that this project I've started has a long tail. I don't want to be tinkering with 2011 Leafs in 2030 anymore, so I need to think about my exit strategy and any decisions that is contingent on right now. So I'm not publishing any leaf-specific code.

I'm implicitly endorsing... related activities though. As of now, Dala is more or less the only other person in the world intimately familiar with my code and thus able to meaningfully continue where I stop. He's been publishing some reverse engineering and useful data that you can really only know with these kinds of tools and code at your disposal, which I will never try to stop. Likewise, I will be publishing 'dangerous' functionality open source, such as modifications to throttle curves, possible future comma.ai or related library support, etc. etc. Things I can't reasonably upgrade on the Leaf myself but that some people might be interested in trying out on their car for funsies on a closed track. The boring 'this just has to work'-code will remain under wraps though.
 
I'm thinking of building my own ev out of a 1973 Opel gt. I found a guy that is willing to sell me 2 x 24kwh at bat are at 70% for $500. I don't have anything for the drivetrain and haven't purchased the batteries yet.

Originally I wanted to put a fwd gas motor and a rwd Tesla motor and transmission in it, to run a hybrid AWD system but the gas motor would need to have an alternator big enough to power the motor which isn't possible from what I'm told. Even with a big battery.

So I'm looking at just a rwd electric motor but I can't afford a big battery pack so these 2 used ones are my best option.

What I've read things I'd want:

A way tmto actively balance both batteries and each cell that I think would require 3 sets to do it properly.

A way to have the batteries disconnect when they hit 25% so they wouldn't get damaged when sitting for long periods of time. I'm reading that they will continue discharging if the 12v is discharged which makes no sense to me.

Having the charging system be able to switch charging modes, revive when dead that's basically trickle charge, slow for all night, normal, quick charge.

A maintenance schedule that will not allow too many quick charges, maybe once a week because I'm told it hurts the battery if done all the time. It could perform a maintenance check of the cells once a month for status updates for cells going bad.

Is the cooling system in when charging? If not, can it be switched on by this, especially when quick charging so it will make sure no possible damage occurs?

Someone already mentioned the setting to keep the charging to 80% with the option to charge fully for those times when someone will need the extra juice?

My car doesn't have any other can bus stuff and I don't want an immobilizer. I'm looking into if the Ac is just an electric compressor with everything the same it if any use a ceramic block to transfer heat and cold to one side just by reversing polarity.

The one major thing I'd like to see is the ability to use a power converter to change the amount of voltage from the battery as it gets lower so it stays a constant amount. I haven't read that any uses this method. Being able to buy a lower voltage high amp battery that is cheapest at the time and the converter making sure the car is getting what it needs would be really nice. No more proprietary battery. Afterall there are 12v to 380 inverters...

I don't know if that is a dumb idea but I don't know anything about this.

I'm hoping to find someone that could help me find the parts and assist me in putting it together.

Then again this would probably make the car very heavy where as a 1000cc turbo motor with 250hp and 150ft/lbs of torque would keep it a 1400lbs car.

I'm going to try to figure it out, but I think a battery would make it well over 2000lbs.

I hope you his gives something to think about and if not, you can delete it
 
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