Hey I’d like to get one as well. Shipping to the United States!
Question: what would it take for this to be able to power on the board?
Great! I will add you to the list 
Regarding your question… The receiver would have to be powered in some way all the time, and being able to turn on/off some kind of soft switch (such as a vedder antispark). It’s something that I don’t have any plans for 
Why can’t you charge the battery with the boost active? Is it the design of that circuit that doesn’t allow it?
The booster circuit I’m using can charge the battery while boosting. In fact my design requires the nunchuck to be ON while charging so I don’t have that problem.
- push nunchuck button Solid state switch sensor input will be grounded and the switch will supply battery voltage to the booster circuit.
- The booster circuit will feed the arduino with 5V. There is a feed back from the arduino to the solid state switch. The solid state switch need 3-5V on this feedback to remain active… if not… it will turn off. When the solid state switch board is activated, it is possible to charge the battery using the USB input on the boost/charging board. Its charging an empty 400mAh lipo with 700mA. Maybe not optimal but its good enough for me.
If the solid state switch is not active, the battery is not connected to the circuit and i cannot charge. The charging/boost board would just indicate “fully charged”
In addition, I have implemented a couple of safety/ timeout features and there might be some pull up/down resistors at some places that I have not mentioned. I don’t remember all the details in my head right now and my phone with all the documentation got lost 
Maybe this is all confusing but here is quick drawing and the mess inside the nunchuck 
I can send you the code for the nunchuck and the board 
/Simon
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Nice build, I did make a Nunchuck remote just like that a year back, however, it was a lot messier than yours 
It’s not easy to fit all that wire and electronics in such a small case!
That’s exactly why I choose to use two different boards. I can charge my remote without having to turn it on, and the boost circuit will only draw current if the remote is turned on. A boost circuit uses a very small amount of current while connected - even though no current is drawn from it.
I would like to see your code thanks
Just test printed
I have to say that I still think it would be much cooler, to use the button as a “toggle switch” for various info pages on the screen. I dont get the “safety trigger thing”
To toggle between, batt level, speed, and distance would just be awesome
I know that @DK-Odense thinks the same, he saw the remote today btw. But it’s your call, and your project.
I´m looking forward to build this thing…
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Looks amazing! Love the red color How did everything fit?
I know a few of you guys don’t love the safety trigger 
… and that’s why I am making it possible to change between three settings for the trigger: Killswitch, Cruise control and the option to use it as a toggle switch for screen
I am working on a settings menu, and saving the settings on the EEPROM! This is also needed to change wheel diameter, cell count and motor poles (used to calculate speed, distance etc.)
EDIT: Love the rubber band, why didn’t I ever think of that!!!
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Now we are talking 
I had to file a little bit in the throttle and trigger hole, for a not so tight fit. But other than that, no problems. I think i`m gonna try printing the throttle wheel in tpu, to se if i will get me a little better grip feeling.
The rubber band is just temporary, so i could try it out I dont think it would work nice in the long run
I had some springs from an old gimball (RC remote) but it was to short…
Btw. I`m using the Metr app. at the moment on my VESC, and with the wheel diameter, cell count etc. dialed in, it just works freaking awesome, i would love to have these features on my remote
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I found a nice way to enter the settings on the remote with only the throttle wheel. To enter the settings menu, you will have to give full throttle in 5 seconds, without clicking the trigger. However this only works, if the trigger is programmed to be used as a “kill switch”. Otherwise, I would not have a way to differentiate between full throttle and “enter settings”. To fix this, I would need a way to enter the settings, without using the throttle wheel, f.x. an extra button somewhere.
It should be quite easy to add a small tactile switch to the top shell by simply drilling a hole, and gluing the switch in.
I have added VESC real-time data, however, I am having problems calculating the speed based on the ERPM. Does anyone have an idea of how the calculation should be made? I have tried RollingGeckos approach, but it doesn’t seem to work very well.
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First, you must convert ERPM to RPM: RPM = ERPM / 7 Km/hr = radius (in metres) × RPM × 0.10472
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Hi, that looks absolutely awesome.
I was wondering if the trigger is set to cruise control or screen toggle could you not hold the trigger then push throttle for 5secs. It would save adding an extra button.
I was wondering if we could help with development and improvements when we get the prototypes but you’ve got it all in hand and then some.
Thanks for all your effort.
Thats really awesome!! Great work!! 
@lox897 Thanks, but I believe I got a breakthrough. However, nothing like the calculation you came with 
. Why would you divide ERPM with 7 to get RPM? As far as I understand the VESC counts 1 ERPM for each back-emp it measures. So to calculate the RPM of the motor I believe it should be:
RPM = (ERPM) / (motorpoles * 3)
So if I had a motor with 14 poles, the RPM of the motor could be calculated by dividing ERPM with 42. To calculate the speed from RPM is quite simple from there, that is if you know the gearing ratio and wheel diameter.
Speed = (RPM * ratio * d * pi * 60) / 1000000
The wheel diameter d is in millimeters and RPM in minutes^-1. I then multiply with 60 to convert minutes to hours and lastly divide with 1000000 to get the result in km (1km = 1000000mm). What do you think about my calculations, am I wrong?
@Neilfenstein thanks man ! Yeah, I thought about that option too, but I believe it is too risky (could easily be activated while driving). However, instead of adding a new button I found another solution. My idea is that when the remote turns on it checks whether or not the trigger is active. If the trigger is active the settings menu are loaded, and if not it simply turns on normally. This way you can only access the settings if you restart the remote - do you think that’s a problem?
@zeah Thanks! I am glad you like it
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I’m pretty sure you divide the ERPM by the number of pole pairs in the motor. Just copied it off @evoheyax 's thread so maybe he can input some advice
@lox897 Hmm I don’t know, maybe the ERPM is different on a VESC 6? I am getting pretty accurate results with my current model at the moment. Would like to hear what @evoheyax thinks
I have updated the display a little further, with some “wifi” icons indicating the signal. I am pretty much pleased with the looks of it 
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My understanding is as follows:
The RPM is RPM = ERPM / (Number of motor poles / 2 )
Then multiply it with the gear ratio and circumference of the wheel and you will get the speed.
See one of Vedder’s blog posts about designing the drive train: http://vedder.se/2014/10/chosing-the-right-bldc-motor-and-battery-setup-for-an-electric-skateboard/ Note: he is referring to a maximum ERPM which is not valid for the VESC 6.
Yesss …!! this is just awesome …@solidgeek please count me in for testing. I am in Poland. I’d love to put my hands on this . By the way do you need some help with the graphics ?? I’d love to help with some custom designed icons I think it would look better instead of WIFI icon.
And by the way how is the signal ? is it reliable ? did you had any losses when riding in the city ?
That’s exactly what I said… Most motors have 14 poles so the number of pole pairs for mine was 7.
I have sent the files to my printer guy - but will only get them back next week 
In the meantime I was thinking about buying the rest of the parts.
@solidgeek: It would probably be easier if you could send me the required parts when you order them in bulk anyway.
Would that be possible (living in Germany btw)?
@oyta I don’t really think Vedder is mentioning the ERPM to RPM conversion in the post? However, I think you are right. My calculation only worked because I calculated the gear ratio wrong. I calculated the ratio by dividing the wheel pulley with motor pulley, which makes no sense if I want to find the speed of the wheel. It should be the other way around: ratio = motor-pulley / wheel-pulley.
RPM = (ERPM) / (motorpoles / 2)
The speed can then be calculated in the same way as before
Speed = (RPM * ratio * d * pi * 60) / 1000000
I just updated the remote software, and the speed seems to be precise !
@lox897 Yep I would still like to know how the VESC measures the ERPM to clarify why the RPM is calculated like so 
@Maxid That is a long wait time 
! Sure thing, no problem. I am still looking for good quality surpliers (mostly from China), so it probably takes around 3 weeks until I got all parts ready to ship.
He is on vacation this week - that’s why. Otherwise this would be done by tomorrow. But since it is the printer at work I am not complaining if I have to wait a little 
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