12S Peacemaker build

crstophr

1 mW
Joined
Jan 8, 2009
Messages
10
I posted another thread a little while back and wanted to follow up with my build thread.

Goals:

Great hill climbing ability
10+ mile range for possible daily commute
Reasonably reliable
Charge batts in place
The knowledge to troubleshoot and repair
A professional finish

After lurking here for quite a while I finally decided on the diyskateboards dual motor kit. Feel free to take a look at the components/specs at the website if you are curious about the details. I'm going to spare us a rehash of the typical information and just focus on some of the challenges, differences, and details.

Why 12S? Initially I was planning on 8S and had already bought 2 zippy 5AH 4S packs. My commute is going to be about 5 miles each way and although I'll keep a charger in the office I wanted to be able to make it through a whole day without a recharge. When I realized I had maybe barely enough juice for the 10 miles I wanted to add capacity for some comfortable head room on distance. Since I already had 2 4S batteries I decided to just buy a third battery and run it in series which should give me 12-15 miles. I didn't need the voltage but I did need the watt-hours.

I planned to use a smaller deck but when I took it in to a local skate shop for grip I ended up walking out with a new deck. It is a LandYachtz Peacemaker. 36" with a kick-tail. With the enclosure I'm able to run the front trucks one set back from the foremost holes. The rear trucks are all the way back.

Some pictures of the 95% completed phase 1 of the build.

Side on:
2015_04_10_17_24_40.jpg


Bottom:
2015_04_10_17_23_20.jpg


The enclosure was a dream to work with. Those batteries I got fit perfectly and snugly side by side with just enough room to run power cables under them. They make a nice dividing section that allowed me to put the receiver on the other side of the case from the ESCs.

2015_04_10_17_26_55.jpg


Speaking of the receiver... my biggest problem was that it didn't work reliably inside that aluminum enclosure. I spent a day rearranging the layout, moving motor wires, etc trying to keep it clear of interference. No matter what I did I lost connection constantly. See that little black nub on the bottom of the enclosure? That's the nun-chuck receiver sticking through the panel with the arduino electronics connected to it. A little dremel surgery and I created a hole just barely big enough to force the receiver through. It is in there tight and I may add some reinforcement. This solved all my receiver issues.

Here is why I'm only 95% complete... The power button that came with the kit doesn't seem to be working for me. When I plug it in, no matter how I press it the light stays on and the circuit stays connected, and after a few minutes the button becomes surprisingly warm. I can't seem to turn it off. I'm confident I have it hooked up correctly so maybe it's just bad.. I'm hoping it can handle 12S voltage because it's such a nice power option. I just haven't followed up on the switch yet, but once I install that and do some cable management in the enclosure this is more or less done...... for now.

Sadly at the moment those two black wires are my main power switch. I'm about to add an in line resistor to yet another connector to avoid the sparking problems but I can't wait to have a real on/off switch to use.

She weighs in at 18.2 pounds. I'm thinking about carry straps/bags... Any recommendations for a long board bag?

I have about 4 miles on it in the past two days. Just shakedown rides but so far it's performing incredibly well. It has been 25 years since I rode skateboards so I'm just trying to ease into it. It's amazing what the body remembers without you having to think about it.

The first thing I did after my initial testing was turn the motor acceleration setting all the way down to low. Currently the motor force setting is still on max but I'm sure I could turn it down to 50-75% and never notice the difference. I like having the ability to dial things back for safety, efficiency, cooling, etc.

One of my first thoughts is to dive into the nun-chuck receiver code and see if I can customize the throttle and breaking curves more to my situation. I'm also thinking about remapping the lower trigger button as a dead man's switch so it needs to be held down for the throttle to work. I realize this wouldn't be to everyone's liking but for me I might appreciate the extra safety. The brakes for me seem ineffective for much of the first half of the stick movement and then come on too strong too quickly. I'd like the force to be more linear.

I'm planning non diving into some arduino LED control anyway (diff project) and later on I may decide to add some adafruit LED strip lights to act as head, tail, or marker lights. I may add a second BEC and with sufficient 5V power on-board there are many, many possibilities in LED control.

That's it for now. Any questions or comments?
 
Why straps on the aluminum enclosure? Think about using M3 thumb screws for it? I think the next enclosure will have a slide top as I swap batteries often. Just need to figure out a way in which it will be fairly secure on the board. Of course it has to slide out sideways as there is no option to slide it towards the trucks.

As for the power switch. It works great. I've been using it on 12S. Send it back and I'll replace it. I sent you an email too.

Nice job wiring the Wiiceiver. It works great once you get the placement sorted out. Beto has no issues with it what so ever as well as psychotiller. Placement is key too bad the nyko kama doesn't come with a better stock reception to the receiver. I guess, they also only imagined that you would be using it within line of sight.
 
I started off with the thumb screws and was having problems keeping myself from cross threading them when in a hurry. The velcro mostly just gives quick access although I believe they support the weight of the batteries well by distributing the support along the lid rather than only at the ends. I put a bit of tension on them and they seem to be holding it all together well.

Thanks for the switch exchange! I cant wait for the proper power button. Sorry for the late reply I've been away most of the last week.
 
okp said:
this enclosure is really dope !

It's my enclosure but it's hard to open since 4 bolt holes need to be unscrewed to open it. The next one I am going to make the top enclosure slide through the sides.

Still trying to figure out how it will hold that way it just doesn't slide it automatically.
 
Update with some mods and energy stats.

The board is now a part of my daily commute. It's not a ton but it gets about 1.5 miles a day of use shuttling me to work in SF. It's also my preferred platform for local errands, shopping, coffee, runs, etc. 4-5 mile runs on the weekend are common. I often gps track my rides and I've got over 100 miles on it this far. I've had one fall which unfortunately damaged the wii nunchuk. I had a spare and bought another but I need to swap this over to the memorex setup soon. I finally turned up the motors to 100% along with the brakes.

I now have a working power switch and recently installed an LED volt meter. I covered the holes in the front panel of the enclosure with a grill so the ESCs can still get some airflow but I hopefully won't find any more rocks in there:) (pics below) I'll install a fusible link for a bit of aver amp protection on my next pass.

I spent a lot of effort tracking down rattles in the enclosure. By far the best mod I made was to add handles to the sides of the enclosure. I used webbing with sections of silicone vacuum line for hand grips. They allow me to carry the board like a brief case.

I just got my watts up setup inside and have some number from my ride today. This was bike paths and streets, all flat terrain, stops and starts at stop signs, lights, etc. I don't exactly believe the estimated range... or maybe I don't believe the rated capacity on the HK Lipos. I calculated range by both the rated pack capacity as well as comparing the avg resting voltage of a cell vs the Lipo V vs capacity chart I see posted around. 17mi by stated pack capacity. 10 if 3.89 is actually about 55% remaining capacity.

Batt capacity 5 Ah
Batt Lipo Cells 12 S
Batt end V 46.7
Bat Max V 50.4
Chart cap by V 55 %
End V/Cell 3.891666667
Batt Wh 252

Distance 5.5 mi
Ah used 1.707
Wh used 81.3
Ah/mi 0.3103636364
Wh/mi 14.78181818
Pct per mile 10

Est range by stated 17.04797048 mi
Est range by chart 10
 
Nice Chris...Where in SF are you riding? It's pretty awesome. I've been riding for over a year and probably have well over 2200+ miles. I save about 3 to 6 hrs on my commute every week. I'm also only a mile away from work too.

I have a new enclosure soon. I'll send you one. It should be a much nicer fit.

From the 12S 5ah setup. I seem to average about 12 or so. I seem to like to throttle it at though.

12S 5ah is 222 Watt Hours
The avg seems to be 5Wh for .31 miles.
Which makes a 12S 5ah capable of about 13.76 miles.
 
Torque,

I'm riding around SOMA mostly. I'd love to check out the new case!

Here are a couple more pics showing the handles and the mini Volt meter.

2015-05-30 18.00.31.jpg

2015-05-30 19.26.08.jpg
 
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