Existing telemetry setups send voltage and current info already though, don’t they? What type of data would you want to see sent that would be different from that? Having the Voltage x Current = Power displayed and logged somewhere (in W) versus what existing units display/log now?
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I love this idea but I don’t think it can be done, not easily. The tag needs to be carried by us (not in the board) or otherwise we need to carry a battery powered device to query the tag in the board. Also, the tag in the board would have no way to signal the AS circuit that it was time to power up.
This means the board needs to have the tag reader in the board and either be awake all the time, looking for a tag, or would need to occasionally wake up to look for the tag. This either drains the battery or causes to wait a long time for power up.
I’ll have to give this one more thought…I’m sure there is a way. 
This could get ugly real quick. Not sure if it would be universal for all setups. I like the idea though and it’s worth thinking more about.
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Possible issue…the tag reader in the board drains the battery and so would need to either only occasionally wake up or something else wakes it up and then tag reading is done. Doable though. 
Physical switch or something else…magnets, NFC, touch switch?
Beeper or click? Or something different?
I don’t know what sound Robogotchi makes.
Best detection method for braking?
Regen current flow? Accelerometer? PWM/PPM signal?
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what if we do it the other way round, like how our phone can read nfc / rfid card, we can hold our phone to trigger the nfc / rfid “verification”.
we can worry about what security measure we put in later for the handshake part after the tag is read-able
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I think this would be the best way to implement AS-switch-based brake lights.
But does everyone use lights that are directly connected to 12V (that can be dimmed)? Or do some use “smart” lights or something with a controller between the 12V power and the lights?
The latter probably couldn’t be dimmed.
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Unfortunately, AFAIK, the tag that is inside the board can’t activate or signal that it has communicated properly with a device. It only transmits its stored data when queried properly.
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ah gotcha
Well, with people like @Esk8_Spirit pushing 7kW just riding on roads in 4WD on 12s, they are already pushing more than the 150A that the Flipsky Antispark supposedly is safe up to. So I’m just saying that if you want to create a superior antispark, increasing that limit even higher might be needed. Of course, 150A will be fine enough for 90% of people, but 100A is probably too little. If we’re talking high voltage, then ~120A would probably be fine.
I’m not sure how many 2WD setups can achieve such power output, so maybe if you allow using multiple AS in parallel this is not an issue.
As long as it takes to climb up the hill 
You should check out @Esk8_Spirit 's youtube channel. He has a watt meter on screen, could give you a good idea of usage pattern by extreme riders like him.
Probably not that often, but on a mountainboard – maybe constantly.
anywhere between 15 minutes and an hour is fine imo.
4 seconds or more would probably annoy me and most people. Sub 2 seconds would be ideal.
In the 12s world – yes. Unless you think you can compete with Flipsky on price 
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Longer than you think. At least an hour, at a bare minimum. 128m or 8192s or 8388608ms would be ideal IMHO.
It’s annoying when you’re in the grocery store and you go to leave, and your vehicle turned off while you were inside shopping.
Also if you’re working on the programming or something, short timeouts kinda suck.
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As fast as feasible. “Any rotor movement at all” is ideal, but a hard push otherwise.
I’d just charge the caps as fast as possible, so the turn-on time is set by the load capacitance, and not by a timer. (Charge holding a specific current or a specific resistor wattage, until nearly full) The more ESCs/caps you connect, the longer the turn on time would be.
A logic-level enable input that’s pulled low would be great, in addition to the momentary switch logic.
I personally prefer the second one.
These aren’t mutually exclusive, as loopkeys clearly demonstrate, but when you start adding “good looks” and “easy to operate” as requirements, then I agree.
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No resistors to limit the current. Cap charging speed is determined by certain MOSFET characteristics and ratings. This means charging is controlled by a timer I set based on the MOSFETs I use and the highest capacitance the switch will be rated for.
If the capacitance is a lot lower than the switch’s rating then the charging will be very quick. If the capacitance is at the switch’s rating then it will take the max rated time (a second perhaps?).
There is a chance that if I can charge the caps slowly (time TBD) then I can just let a little current squeak through, and not overheat the FETs, and let that run until the voltage is high enough to turn the FETs fully on. I haven’t done the math yet though. It all depends on the max capacitance rating.
This input will be subjected to a lot of electrical noise so I might go with a differential signal, RS-232 or similar. Having these switches turn on/off when I don’t want them to would probably be considered by many to be A Bad Thing.
Agreed, but for an electronic AS switch it sure is.
Just make a motorized loop-key, lol
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The biggest problem is that a reliable 200A continuous rated switch would need a couple dozen MOSFETS, 1/4” thick bus bars, a couple circuit boards, be huge, and cost a lot of money.
The few people who truly needed that capability might pay for it but for those who just need the switch to handle 150A bursts the cost would be way beyond what they thought was reasonable.
But possible options include two (or more) different models or a modular design to increase the current handling.
Thanks for your thoughts! I’ll check out Esk8_spirit’s YouTube channel.
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The total ampage depends if it’s a chained system or not don’t neeed 4 x 200A AS
Single ESC 80-100A continues. 120-150A burst
look at battery’s 4p q30 most common battry pack outputs 80A continuously.
Reliability is a absolute must it’s why so many people don’t bother with AS switches as we sick of replacing broken ones.
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It will tell precisely how much power the motors themselves are pulling.
People might have other devices that are not downstream of the antispark and so the numbers reported by a battery may be misleading.
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How’s this project going?
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Early stages of defining the requirements, circuit design, and checking component availability. Unfortunately, it looks like the reliability and functionality of a $150 device is desired but I think very few would pay more than a small fraction of that. 
I’m not willing to sacrifice reliability to bring down the cost so it’s going to depend on what the community will pay for a reliable but “dumb” switch.
I think many would prefer to take a chance with an inexpensive, but much less reliable, switch than pay three times more for something that would last forever? I would need to sell a lot of them to keep the price down to merely very expensive.
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why not just have more then one variant? one for high current and one for low current. If someone is trying to make a budget board then $150 would be a lot but they probably also wouldnt be pulling that much current to begin with. but if someone is building a 4wd monstrosity then I doubt that an extra $150 would matter much to them.
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