Over My Head First Board Build (need advice)

[laxplayer9009]

Hello,

I need a side project for my down time and then I stumbled on this site and got hooked. I haven't decided whether this is going to be a ground up build (new/custom deck, custom motor mount, etc), or use off the shelf components such as torque/enertion mounts, off the shelf deck, etc.

I have decided on a couple of components however:

(1) Turnigy SK3 6374-192kv Motor (12S):

http://www.hobbyking.com/hobbyking/...SK3_6374_192kv_Brushless_Outrunner_Motor.html

Single motor, I don't think a dual setup will be necessary.

(2) Alien 6S 8000 mAh 35C Lipo Batteries Flat Config:

http://alienpowersystem.com/shop/6s-batteries/alien-6s-8000mah-35c-lipo-battery-flat-configuration/

I saw someone's build on here who had they're battery setup switchable between series/parallel, so i'm going to adopt that into the design. In series it'll have 6S 16,000 mAh capacity for long range capability, in parallel it'll have 12S 8,000 mAh capacity for pure power (should get decent range as well)

ESC: (Still up for debate)

Leaning Towards:
http://alienpowersystem.com/shop/car-esc/alien-150a-2-12s-car-esc-hv-twin-2/

If vedder's ESC is 6-12S capable then i would most likely go that route since i'm only planning on a single motor setup.

Wheels:

All i know is that i'm going to go 90mm size (roads around here aren't all that smooth).

Belt:

haven't looked too much into this, but I was thinking a 9mm. Some advice on this would be helpful.

Gearing:

Multiple setups but i'm going to go with a 15T/30T setup to start. Doing the math out i get roughly 38+ MPH assuming 85% efficiency

Controller/Transmitter:

I'm going to build some kind of custom arduino based controller, this will be the fun part that i can mess around and expand the customization of the whole project. It'd be cool to have a deck mounted LCD screen displaying the current selected voltage (6S or 12S), the % of power level, custom power levels (possibly on the fly) with reduced throttle, current speed. There's a lot of options.

The idea is to over build it and tame it down to a level that works for myself. That way I have the option to crank up the power if i want, have the ability to extend the range, etc all in a relatively small package.

It's going to be a slower build as I'm usually pretty busy but it'll be fun for sure! any feedback/advice is welcomed!

 

[torqueboards]

Why I wouldn't buy an APS ESC http://endless-sphere.com/forums/viewtopic.php?f=35&t=67998

Why I wouldn't buy an Alien 6S 8000mah battery pack
You can buy (2) 4S 16ah Multistar packs from HobbyKing and/or even 5S. They even have a 6S option. My favorite option is going with 4S 5000mah 20C hardpacks from HobbyKing. They're only about $24/ea or so.

For ESCs
Vedder's VESC is a great option (SilviaSol can solder one up and/or Onloop/Jacob have a beta buy going on) and/or the 12S TorqueBoards ESC I have on my site has also working great compared to the older APS style ESC's which I use to sell. Has an ESC Programmer Card which makes changing braking configurations and/or acceleration on the fly so much easier.

Belts;
9mm is adequate but 15mm is definitely better. I should have some 18T/36T pulleys that will fit 15mm or 9mm belts. 15mm will add drag but if you don't plan on kicking it's not much of an issue.

Gearing
Are you sure you want that kind of speed and you wouldn't trade it for torque?

Custom Controller
Awesome! Can't wait to see your controller. I've been planning on making one too but haven't fully started just yet. http://endless-sphere.com/forums/viewtopic.php?f=35&t=67840.

We should definitely collaborate and work on building one together and open source it. I was hoping to use Austin David's old source code or similar. PM if your interested.

 

[laxplayer9009]

My limited knowledge is going to be displayed but..

For the ESC, whats the difference between OPTO and a non-OPTO ESC? I've read you need a BEC, UBEC, SBEC. not exactly sure what those are, i'm assuming regulated DC supplies but why do you need them for an OPTO?

Belt: I was thinking of making a second build with the Hub Motors that are being developed on here, so that would be my kick/more free wheeling board. 15mm it is

Gearing: I was under the impression that the 1:2 gearing was decent in terms of torque? Unless you're talking about the large wheels. The motor on 12s should spin ~7200 RPM (85% efficiency) and its ~2750W. The 192 kv is lower than i've seen on most builds on here so I was thinking that would make up at least a little in terms of torque and the higher voltage would allow higher speed.

Would you suggest a lower ratio?

Controller: That link was what sparked the idea in my head. I also saw someone mount the Voltage indicator in the deck of the board, which sparked the deck flush mounted LCD screen idea. I haven't given it much thought other than what could possibly be done with it but it'd definitely be cool to collab and actually get something done.

I don't like the slider though, some kind of thumb wheel slider (one of those ring sliders if you know what i mean) or larger video game controller trigger type design. an analog joystick that only moves vertically may also be a better option. anything that provides resistance and pulls back to neutral position, although his dead-man switch is a nice alternative to that

 

[torqueboards]

What is OPTO?
OPTO means that the ESC has no power source. Ideally, this is a better option anyways because UBEC's are better than most internal bec's on ESCs usually ESCs 6S and under have a built in BEC unit.

What is a BEC/UBEC?
A BEC is a Battery Eliminator Circuit. A BEC/UBEC (The U stands for Universal) basically takes your full voltage and brings it down to a 5V power source to power on your RC Receiver.

If an ESC does not have OPTO. The BEC is usually built in.

If an ESC says OPTO. This means you will need a UBEC as the ESC Signal Wire won't give off power to power on the RC Receiver.

Gearing
1:2 is very decent. It's my favorite but if you end up going high voltage there's a ton of extra power. If you don't need to go 38mph and only need to reach 30mph. You can add more torque and make your max 30mph.

You can always use the added torque and if you never go past 30mph. It's just kind of a waste.

You can go with 2.25 or 2.6. I would have to calculate it out though. That's just an estimate.

Controller
The voltage indicator on the board is a nice feature but IMO would be even better on the handheld controller . I like the idea of a small LCD screen on the top of the controller.

The slider can also spring back to neutral. The video was only inspiration.

From what I've heard out of all controllers it seems that most people enjoy using the E-Go controller perhaps maybe even more than the Boosted controller.

 

[laxplayer9009]

Oh that makes sense. Does any other place sell lipo batteries? I'd ideally like a 6S in something larger than 5800 mAh.

The 2.6 would put it at ~30 MPH (15T/39T) 2.25 would put it at ~35ish (12T/27T). The 2.6 sounds good to me. Another question i had was how do the motors react when you loose receiver signal? can you get thrown off the board?

A screen along the lines of these would be ideal:

http://www.adafruit.com/products/931

http://www.adafruit.com/products/684

http://www.adafruit.com/products/938

small enough to not be overwhelming, probably no need for a color screen though.

I like the size of the booster contoller but the functionality of the e-go seems better. Personally i feel like a smaller package controller is preferred over a large one. i wouldn't want to have to carry anything longer than say a Gen5 iphone in my hand while riding.

 

[torqueboards]

HobbyKing sells the cheapest lipo's I think.

That first one looks nice and compact. Other options are nice too for more stats.

Majority of time the motors will just free roll if you loose connection.

Color screen wouldn't be that bad Would be a nice controller.

I was thinking the handheld could be small and the LCD screen just sticks out on the top.

 

[laxplayer9009]

That was my thought as well about the screen. The board would probably drive the overall size but screen would need to be >1.5" most likely.

 

[laxplayer9009]

ordered some parts to test out the controller w/ screen concept. i'm still looking for an analog throttle setup. i haven't been able to find a thumbwheel (for a reasonable price). if anyone has come across anything interesting that could be used as an analog throttle control let me know.

also, i'm looking for off the shelf enclosures/formfactors that could house a screen. would need ~2"x2" flat surface to mount nicely. the smaller of the screens would only need ~1.5"x1.5". the wii nunchuck doesn't have any flat surfaces. a wiimote or whatever the normal remote is called may work.

 

[torqueboards]

Try Polycase Handheld cases? - http://www.polycase.com/handheld-remote-control

 

[laxplayer9009]

thank you, that'll do the job for testing

 

[laxplayer9009]

got in some toys and quickly just made sure that it was possible for the arduino micro to power the displays. the answer is it can. now its time to get to work.

font size for all text is 1

128x32 Monochrome (I2C):

the white background was just showing what the options are. only get 3 lines on this display

128x96 16-Bit Color (SPI):

threw in some different colors, 9 lines on this display at size 1, i believe you get 3 at size 3

nrf24l01+'s coming in along with other needed components to get a prototype up and running. anyone been able to find a thumbwheel?

 

[torqueboards]

Haha awesome stuff.

 

[laxplayer9009]

had a couple of minutes so i got a "turbo button" and analog joystick wired up. a few caveats, the joystick kinda sucks so its all over the place and i didn't have time to smooth it out, also not a lot of travel. throttle is limited to 75% without pressing the button. the button expands the range to 100% throttle/braking. this is just to show the proof of concept, not meant for actual functionality.

also, ignore the relatively long fingernails..

https://youtu.be/OG7cjIuA-cE

 

[torqueboards]

Yeah, that's the downside for the joystick's not much travel which makes the throttle control not as precise.

Your going to be using NRF24L01, right?

I was trying to look for a spring loaded slide potentiometer but couldn't find nothing.

 

[laxplayer9009]

i ordered an actual joystick, something like whats on the wiiremote. i'll see if thats any better.

yes i'm going to be using the nrf24L01+, should have it saturday to play it.

yeah i wasn't able to find any spring loaded slide potentiometers either. i'm guna try to diy one. or maybe design a different kind of control. have a couple of ideas in mind but it'll be $$ to actually have them built

 

[laxplayer9009]

new joystick seems to have way better sensitivity

https://youtu.be/HuCYUwhXE-0

unfortunately the nrf24l01+'s didn't show up in the mail today

 

[torqueboards]

Looks good Hopefully, plan to get there too. I need to learn arduino unfortunately.

Does the joystick have a bit of resistance? I think it's very sensitive too.

Include your video in the post.

Where do you plan on mounting the display unit?

[youtube]HuCYUwhXE-0[/youtube]

 

[laxplayer9009]

i couldn't get the video to show up in my post? the joystick does have some resistance to it, but there's a decent amount of travel on either end that doesn't actually translate into output. I'm still trying to figure out what exactly i want to use for the throttle, this was just the best option i've tried so far.

right now the plan is as follows:
I plan on mounting the display on a wireless controller. with some form/s of throttle&braking control and probably some cruise function. this will all be run through an arduino micro. I have to design up a 3d model, but i need to find a throttle/braking control that i like first.

an arduino uno is going to be in the electronics enclosure and will relay the throttle commands from the micro to the ESC. the uno will also have a GPS module for speed, that upon receiving throttle commands will send a reply to the micro with the current speed and subsequently displayed on the OLED display

all wireless will be done via nrf24l01+'s, the gps will be the slowest portion of this whole setup. it updates at 10Hz, but I couldn't think of a better way to calculate the speed so i'm going to roll with it.

 

[torqueboards]

You just need this code for the video - HuCYUwhXE-0

Nice.. What your doing is pretty much what I want to do.