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My quest to make motorcycle riding that tad bit safer

gill.net.in

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Re: My quest to make motorcycle riding that tad bit safer

#11

Post by HPsquared »

It's very important to consider failure modes when adding something like this.

You should ensure there's no way the new addition could prevent the brake light from working if the electronics were to fail (either electrically, software glitch, corrosion, bad connection, etc). Because failing to light the brake lights upon braking could directly cause an accident.

Secondary perhaps (though still important) is to prevent false positives (brake light illuminating when just driving along normally). That's still bad, but at least other drivers would be suspicious of it and it's more obvious.

Re: My quest to make motorcycle riding that tad bit safer

#12

Post by mygnu »

Etheryte wrote: post #8

Out of curiosity, wouldn't an accelerometer alone not work for this purpose? I see you've hooked it up with engine RPM as well, but realistically you want to indicate when you're slowing down, no matter the reason, right? Is there something I'm fundamentally missing here? This is a great idea though, and definitely something that more bikes should come stock with. There's a very clear benefit for safety.

Thank you for your question, it does not hook with the engine RPM, but I did have an issue with the sample rate syncing with the engine rpm therefore picking up noise, I solved that issue with randomizing the sample interval with pseudo random numbers.

Re: My quest to make motorcycle riding that tad bit safer

#13

Post by Workaccount2 »

The author did a great job actually building the project, doing a layout and custom design rather than just stitching together off the shelf modules. Good work.

That being said, in 20 years of riding motorcycles and being an ATGATT (all the gear, all the time) kind of rider, I'm mixed on the need for this. It's something I have thought about doing with a direct hardwire to the throttle, but I can't come up with a situation where I genuinely think it will stop a crash. Maybe if someone is tailgating you, but you should be readily letting them pass rather than relying on their reaction skills anyway. Anything that is sudden and requires a large -dv/dt, you are going to hit your brakes. Engine braking alone is usually used in situations where the road/conditions dictates it, so other drivers are naturally slowing down too.

But I suppose it is also an "it can only help" type product.

Re: My quest to make motorcycle riding that tad bit safer

#14

Post by mygnu »

HPsquared wrote: post #11

It's very important to consider failure modes when adding something like this. You should ensure there's no way the new addition could prevent the brake light from working if the electronics were to fail (either electrically, software glitch, corrosion, bad connection, etc). Because failing to light the brake lights upon braking could directly cause an accident. Secondary perhaps (though still important) is to preven…

I am considering adding a watchdog logic in the microcontroller that holds a mosfet gate, if there is any signs of failure in logic it would pass through the normal light signal.

Re: My quest to make motorcycle riding that tad bit safer

#16

Post by jollyllama »

snarf21 wrote: post #2

I ride motorcyles so found this quite interesting. Instead of a motion sensor, why not simply turn on the brakes whenever you down shift and leave it on until the throttle is engaged?

I don't think that would work in cases where rev-matching is used.

Re: My quest to make motorcycle riding that tad bit safer

#18

Post by HPsquared »

mygnu wrote: post #14
HPsquared wrote: post #11

It's very important to consider failure modes when adding something like this. You should ensure there's no way the new addition could prevent the brake light from working if the electronics were to fail (either electrically, software glitch, corrosion, bad connection, etc). Because failing to light the brake lights upon braking could directly cause an accident. Secondary perhaps (though still important) is to preven…

I am considering adding a watchdog logic in the microcontroller that holds a mosfet gate, if there is any signs of failure in logic it would pass through the normal light signal.

A lot is also dependent on how it's wired into the vehicle, as in the main electrical failure modes like open circuit, short to ground, stuck at +12V, etc. Need to be careful about where the responsibility (and liability) is.

Re: My quest to make motorcycle riding that tad bit safer

#19

Post by imglorp »

Workaccount2 wrote: post #13

The author did a great job actually building the project, doing a layout and custom design rather than just stitching together off the shelf modules. Good work. That being said, in 20 years of riding motorcycles and being an ATGATT (all the gear, all the time) kind of rider, I'm mixed on the need for this. It's something I have thought about doing with a direct hardwire to the throttle, but I can't come up with a sit…

EV's with regen braking and manual transmission vehicles are in the same boat: unless they light up when slowing, following drivers will be surprised. The bare standard IMO for all vehicles should not be to light up when brakes are applied but instead any time the vehicle begins decelerating. Adding flashing for a strong stop ~~ >0.75g would be a bonus. Given all the sensors and compute hardware on vehicles -- even bikes -- these days it should just be a software touch.

The Technology Connections YT guy has a whole piece analyzing tail lights and I agree with him.

Re: My quest to make motorcycle riding that tad bit safer

#20

Post by HPsquared »

_ea1k wrote: post #10

TBH, I'm surprised this isn't already common. It is very similar to what EVs do, due to the relatively high regenerative braking.

You'd only see it on newer bikes with ABS, they seem likely to have more sensors and "electronics" in the brake system. In that kind of system the deceleration could be inferred from existing speed signals. I wouldn't be surprised if ABS systems already estimate the engine braking torque directly.
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