4WD Heavy Duty Offroad Monster Board - VESC, c6364 sensored, 12S30Ah, 10kW

[Duffman]

I rode around 500km offroad over the summer 2015, when fall came and the days got shorter and darker I had to build a proper headlight. Before I had done some experiments with flashlights but was never satisfied because there was always too much light directly in front of me and always to less light in the far field and in the corners. I found the perfect solution in a 32W (105 lm/W) high power LED strip in combination with a cylindrical lens.

High Power LED Strip: http://www.leds.de/en/LED-strips-modules-oxid-oxid-oxid-oxid-oxid/High-power-LED-strips/SmartArray-L25-150W-25-LEDs-neutral-white.html

Datasheet: http://www.leds.de/out/media/Datenblatt_SmartArray_2014_V11_ENG(3).pdf

LED Strip Optics: http://www.carclo-optics.com/optic-12750-300mm?opticfamily=strip%20optic

This produces a oval shaped spot, wide in horizontal direction and narrow in vertical direction:

The LED strip and the lens are held by a housing stacked out of laser cut aluminium sheets:

The two different parts in 1mm and 3mm thickness are alternating stacked to produce a housing with heatsink fins:

The stack is held together by M4 threaded rods and Locktite:

The LED strip is sitting in a milled slot:

Completed housing with LED, lens and wires:

The spot has some chromatic aberrations but normally you don’t see them, only when pointing on a wall:

The 32W LED puts out a huge amount of light. It is sold to replace a 150W halogen tube:

The LED housing is mounted on the12mm stabilization rods which connect the front motor holding plates:

To power the LED I’m using a Meanwell LDD-1000HW - a current regulated 1000mA 56V step down regulator which is located in my ‘cockpit’ (black brick in the lower left corner of the last pic):

[Okami]

Insane light, man!

@Duffman do you by any chance know how much lumens/watts Cree XM-L leds produce (commonly used now for flashlights)?

Edit:

Ok, so at max it looks like they produce 10W of light, some of which probably gets eaten away by reflector or lens, if one is used… so we would need at least 2-3 such Leds, to attain the same brightness level / power output as you got for your lights

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They are now included in a lot of headlight lights but im not 100% sure at what power levels they are driven by the circuitry inside of these lights.

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So far one of these lights (with 1x Xm-L cree led chip) have been good enough for me along with ‘‘Zoom’’ lens Im having for my headlight.

But to be honest, now I think 2-3x of these chips at the power level I am getting, would give way better riding for trails/tracks in the dark!

The headlight can take up 2x 18650 but they are connected there in parallel and increases brightness only a little bit when 2x 18650’s are inserted, instead of one.

I’ve also heard there is the XM-L2 led chip out but im not sure which lights offer it and which not.

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If someone missed it, then my headlight has 1x XM-L chip, while there are models out there now which offer 2 or even 3x of these chips in one headlight.

For off-road this is somewhat a quick solution as you dont have to install the light directly on the board, has seperate battery box and u get light in which direction you are looking at.

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Though, im sure @Duffman has way more light for his big board than one or maybe even two of these XML chips can offer

Also I apologize for sidetracking everything but Im just appreciating how much work @Duffman put into creating a housing/sink for these lights, too!

So yeh for offroad and riding in darkness a good light is a must… unless someone ones to hit a pothole, huge stick or something else while riding!

[Mobutusan]

Amazing work, yet again. This thing is like a 7 layer burrito of DIY goodness. Do you mind if I ask what you do for a living?

[mmaner]

@Mobutusan

Do you mind if I ask what you do for a living?

Im gonna guess he is a professional lottery winner with degrees in physics, mechanical & electrical engineering and a red phone to Thor

[Duffman]

@Okami I edited my post above with the links to the LED and optics.

According to the datasheet the strip produces 3283 Lumen at 32W power and 85°C temperature, which results in 103 lm/W. 3 XM-L @10W each would produce almost the same, but usually they are driven at much lower power levels (3W) to get better efficiency.

@Mobutusan and @mmaner Unfortunately no lottery winner but mechanical engineer, doing CAD modeling of plastic injection moulds for 10 years and expensive hobbys like building drones, building cncs, building 3D printers and of course esk8ting

[Jebe]

Take ALL my money !

[Duffman]

Back to my 7 layer burrito ;-):

Because the new tires are gocart winter tires and can officially be equipped with spikes I simply had to try it and bought a 1000pcs set of ‘screw in spikes’:

Each tire can take 132 spikes, at 4 tires this means screwing in 528 spikes and takes about 2 hours:

Ready to ride:

After a short testride:

After a real ride:

In 2015 we had 2 weeks of snow (and 2 weeks of fun!!!), afterwards I simply screwed the spikes out and was ready for spring again. Unfortunately we had no snow in winter 2016 so I couldn’t use them again…:

This was (for reference) a testride without spikes:

4WD eMTB Electric Mountainboard Snow Ride - MBS Pro 90 - VESC - NTM5060 - 12s

And this are some rides with spikes:

4WD eMTB Electric Mountainboard Snow Ride With Spikes - MBS Pro 90 - VESC - NTM5060 - 12s

[DanSkates]

Incredible! Now that’s REAL test right there! Loving your work

[ieatflys]

@duffman i have a question or two for you if you dont mind… im building a similar ish setup for street shredding that mite see offroad once or twice…
what made you decide to run such a large capacitor bank did you choose values for a specific reason or did you just fit what you could to avoid voltage sag so you wouldnt have issues with your vescs blowing up since there prone to it in foc mode due to voltage sag?

I see you have about 6 5000 ah lipos wired to 12s. Whats your actual functional capacity with the batteries wired to 12s? I was having a hard time figuring your values judt out of curiocity…

How do you handle your voltage spark when hooking up power. Do you have a resistor setup to help keep that capacitor bank under control?

Thanks for the replys. Very sweet setup you have

[Duffman]

I wanted rearrange my VESC and cap wiring because I found out on my other builds that short connections and good ESR can keep your ESC cooler and improve your reliability. To keep wires short, I had to stack the PCBs and the caps and just filled the remaining space with more caps…

No matter how many caps you add, they won’t help you with voltage sag, but can compensate for the inductance of long battery wires, which would induce high voltage spikes when switching at high currents.

This is the best and most detailed description of ESR I read in a long time: VESC FAQ | How Many Capacitors & What uF - #48 by FredSaberhagen - ESK8 Electronics - Electric Skateboard Builders Forum | Learn How to Build your own E-board

I’m running 12s 10Ah (3x 4s5Ah x2) per ‘layer’ and can stack up to 3 layers for 12s30Ah. Everything at 20c constant / 30c burst.

To power everything up I simply use an XT90S antispark loop key with a little 100A ANL fuse.

This holds up very well against the 250A burst current I am pulling at maximum like in the beginning of this video:

Offroad Electric Mountainboarding - eMTB

[Nowind]

Haha this board is the absolutely awesome Madmax Killer Vehicle… watching the video and seeing myself strapped to the monster brings a big fat grin to my face… pulling this 11KW was incredible … also whats amazing is the damping properties of this FAT tires, compared to my 8inch racer it feels so much comfortable even on super rough terrain

[ieatflys]

Thanks for the reply and very detailed responce. Sweet approach you have taken… how much rsnge are you getting out of 30 ah? Also did you choose tour capacitence baced on any math or just kind of as many as you could get to fit ?

[ieatflys]

@Duffman. I am in the process of building my cap bsnk for my vesc… what capacitors did you end up going with could you maybe supply a link it sounds like youve found some good ones… also when deciding how many to use and what uf did you calculate in amperage or did you run with the 220 uf per vesc oer 4 inch rule?

[Duffman]

These are the ones I used: http://m.ebay.com/itm/Elko-Panasonic-FR-680uF-63V-Kondensator-105-C-Low-ESR-same-as-FM-854466-/181757988566?hash=item2a519eced6%3Ag%3AINEAAOSweW5VZZHo&_trkparms=pageci%3A14fe1e30-2f65-11e7-91ba-74dbd1806b9b%7Cparentrq%3Aca6b5a4715b0ab1db5fb2259fffe9e50%7Ciid%3A2

For my other board which is also running VESCs on 120A with 50cm battery wires I just replaced the 2x3 stock caps. On this build I simply had the space so I went with 4x7 caps.

Range depends highly on terrain. When driving and drifting on grass I should get around 20km with 12s30Ah. In loose sand or snow I can burn down the same battery on less than 10km.

[Duffman]

I always forgot to show you one little detail, which imo is a big improvement over the stock MBS spring truck system.

Instead of using a spring and an egg shock (dampa), I’m using an elastomer compression spring to get better / softer steering capabilities and better dampening of speed wobbles.

I’m using E 1556/ 32 x 63 from Meusburger (HWS 5724 Aluminium Universalschonbacken, magnetisch Formenbau | Meusburger) original manufacturer seems to be Effbe (EFFBE GmbH: Startseite).

In combination with some simple aluminium bolts it is a drop in replacement for MBS and Trampa spring trucks.

This is a comparison of the usual spring/damper combination and elastomer springs:

Vergleich zwischen Federn, MBS Egg Shocks (Dampas) und Elastomerfedern für Mountainboard Achsen

I’m running these in my Monster an in a Trampa/Next crossover board of a friend for more than a year and am totally satisfied with the feeling of the ride.

[Nowind]

Nice Perfect documentation as always…

[rich]

What a 4WD monster build, wicked man! Just a question according the elastomer spring. Are the thread inserts included and how’s the feel compared to trampa springs with yellow dampas? Looks very interesting

[Duffman]

No, the thread inserts are selfmade, but you don’t have to own a lathe to make some. Just cut a piece of metal to lenght, drill a hole and round the edge…

The hardest part would be to get the elastomer springs, as I don’t know if they sell to private persons…

[nw-esk8]

Now that is a beast of a board…

[skslingo21]

All up weight? Drumroll pleaseeeeee

bababababababababababababababababababababab (what drums sound like in my head)

Youve done a kickass job keeping things light with aluminum sheet!