Yet another Onda Longa build w/APS (issue)

[Wayno]

With the help of my friend kfong and his awesome CNC-fu I'm close to completing my first eSkateboard build. It's an 8S setup with the 4.4kW kit from Alien Power Systems. It's my intention to mount the tupperware container just below the deck which should give just enough room for the power mains to connect to the ESC. Any suggestions on how to hang it so it doesn't interfere with board flex but still be accessible? I might try to find a better case at a later point in time.

Unfortunately I'm having an issue with the Alien 150A dual ESC. On 4S, both motors run, but when I attach the second battery (8S), only the left ESC will spin its motor. The right ESC either doesn't initialize, or initializes but doesn't respond to throttle inputs. I've tried running that ESC by itself but the result is the same, that is, it works on 4S but not 8S. The left ESC works fine on 4S, 8S, alone or when both motors are connected (to their own ESC outputs). I tried using both Auto cell count and forced 8S count in the ESC configuration with the same results.

Any ideas on what else I can try? Both ESCs are configured the same way with the programming software and are running v4.5 firmware.

-Wayno

 

[torqueboards]

Both sides of the controller are programmed?

 

[Wayno]

Both sides of the controller are programmed?

Yes sir!

I also just tried a "load factory defaults" and then just changed timing to 20 degrees and brake at 20% on both ESCs... same issue. Doesn't look like there's any newer firmware available.

 

[Wayno]

Tried running the board with 1 motor (unplugged the motor that doesn't start and removed the belt)... it starts up fine when not loaded but when I'm on the board it just cogs, even with a forward push. Would think that with 2.2kW peak/motor it should be able to get me going. My clamp-on current meter is not working so I don't want to push it w/o knowing how much current it's drawing. Throttle input was limited to a couple of seconds. Nothing got warm.

Any other settings aside from timing that I should play with to try to help with starts? I can post screenshots of the different options available if that helps.

UPDATE: OK, one wheel drive definitely works outside with a kick-start. I think the problem is that the belt is slipping upon start due to the large ratio and small tooth-contact area off of the drive pulley. There's torque-steer upon acceleration so I'm hoping that once I get the second motor running it will eliminate this and also help with the initial launch.

I can switch to a 13T pulley but it's wider than the 12T and even that is already hanging off of the motor shaft. Wish the motor shafts were longer.

One thing I didn't really think too much about before the test run this afternoon is that there is a LOT of vibration that gets through because of the rough pavement. I'm going to have to rethink my mounting strategy for the ESC and batteries.

 

[Wayno]

So it seems that one of the ESCs doesn't like 8s voltages. I'm able to run the board if I partially discharge the pack. Still looking to find the voltage threshold. I made a recording of some loaded starts and find them rough. You can see video here: https://youtu.be/fwAi_18JboU

Settings on both ESCs are:
Throttle curve: linear
Acceleration: soft (also tried medium with similar results)
Motor Timing: 20 degrees
PWM: 8kHz
Timing Monitor: ON
ABS Braking: 70%
Start Power: Auto

Not sure if this is what I should expect or if there's a way to improve the start. It's possible that perhaps the belt(s) are slipping on startup due to the 12T/65T ratio but it's difficult to tell (anyone have a good technique to check for this?). So far I haven't noticed any shared off teeth and the belts are pretty tight.

Tons of power once it gets going... wheels actually loose traction upon acceleration at speed. Power meter showed that I pulled a peak of over 2kW... scary! Luckily I was sitting down at that point.

Lot of vibration on the components in the box.. will have to do something about that. Batteries are mounted in there until I can find some appropriate boxes to mount them below and on the angled parts of the board (one front and one back).

 

[CSN]

How do people like the powered Onda board compared to regular longboard?

Reason I ask is I have an unpowered Onda Longa but when I push board it around I am really unimpressed. Does powering it change the personality?

A couple of things I notice pushing it around is that the wheels don't roll that well when it comes to maintaining momentum. Maybe a motor changes that.

Also when crossing a seam or curb cut the wheels and trucks kick back. The board wants to hit things straight on instead of an angle like a longboard.

The board does seem to lessen vibration somewhat due to the flexy nature.

Just curious what other people think.

 

[Wayno]

Hi CSN,
Not really on-topic but since it's quiet here I'll give you my thoughts. I don't have much skateboarding experience but I snowboard pretty well. I've never had the opportunity to ride any other eskateboard so can't give you comparison in that regard. I've used this board and a "Skupboard" for some land-paddling, which I enjoy. Since I usually do this in the park with an asphalt trail I actually prefer the Skupboard", with a much stiffer deck, for that.

The pavement where I live is very poor concrete so for me a regular skateboard was not on option (I didn't want to limit myself to riding in parks); I had to get something with bigger wheels. The price of the Longa was good and it has nice big 7" diameter wheels so I pulled the trigger. Right now I'm still trying to work out the kinks in the now electrified board. I noticed that the wheel sprockets aren't staying on very well with just the M5 bolts and loctite. Will either try some other type of glue or just get longer bolts, drill through the spokes, and put washers & locknuts on the other side.

I had 3 other people try the board today and 2 of them were able to induce a high-speed wobble in the board. I was able to duplicate the issue with the drive wheels in the front by going fast and then letting off of the throttle. I still have the original elastomers in the trucks and I definitely need to change those out because they are listed for an 88lb rider and / or slow speed. I'm about 165lbs and the board now weights 20.3lbs so I'm way over that limits... and speed was also pretty high.. guessing close to 20mph.

I don't think that wheel momentum, as you describe it, is an issue once the board is electrified since you're no longer kicking. I do know what you mean regarding hitting things... I usually try to hit things straight-on but so far I haven't really had an issue with that aspect.

Peace.

 

[torqueboards]

I should be getting an Onda setup ready shortly. I just don't have the time to set one up ATM.

Onda looks like it should ride good. Although, I have yet to actually try it.

Personally, I really only ride for commuting so smallest deck while still being pretty darn reliable and stable is my ideal board. Preferably, 32-35" 36/37" is pushing it a bit.

Not sure about others but I didn't like pneumatics or ultra big wheels on my setup. Ride can be bouncy at 15-20mph especially with potholes and obstacles. Obstacles you don't necessarily want to ride 15mph over them on a pneumatic board unless your strapped to it. On my stable deck I can just ride over it and/or carve around it with is actually much more fun.

It's also nice lugging around a under 15lb board versus a 18-20lb board that's 42" versus 36".

If I wasn't using it for commuting though. I probably wouldn't mind the pneumatic setup + extra long deck.

 

[higrade]

First thing i will say this is going to kill you, second this is going to kill you. I have a onda longa longboard build single 195kv motor 6s gets me 25miles per hour, i have the red shocks and it wobbled on me throwing me was in pain for about a week.

Other than that this is a dream the best board you can use without a doubt grate range because of the wheels and riding over cracks is so easy. The attention is crazy i get stopped everyday.

I believe you can fix your issue or make it better by getting the drive belt closer to the hub having it rub against the belt guard would be perfect but that seems to make it better for me.

 

[Wayno]

First thing i will say this is going to kill you, second this is going to kill you. I have a onda longa longboard build single 195kv motor 6s gets me 25miles per hour, i have the red shocks and it wobbled on me throwing me was in pain for about a week.

Other than that this is a dream the best board you can use without a doubt grate range because of the wheels and riding over cracks is so easy. The attention is crazy i get stopped everyday.

I believe you can fix your issue or make it better by getting the drive belt closer to the hub having it rub against the belt guard would be perfect but that seems to make it better for me.

Thanks for the info... hope you're fully recovered. Did you get the wobble on the drive wheel side? I've seen that also on the drive-side but as mentioned before I was on blue shocks all around. Last night I switched to red/black on the drive side and red/red on the non-drive side. Didn't get any wobble but also couldn't carve (using term loosely) it any more either. I went back and put blue/red on the non-drive side which I'm using as the front now and I can live with this as a compromise. I was going to drive red/red on the drive side but based on what you wrote will probably keep it red/black. My max speed was only 14mph so further testing is required.

For the wheels I noticed that I can use 30mm bolts where I have 15mm now (to attach the sprocket to the wheels). I have these on order and hopefully that will fix my issue. Green or red threadlocker doesn't seem to want to bind with the wheel material though so may have to try something else... maybe some hot glue and screw them in quickly? If not, I also ordered even longer bolts and will just go through the spokes with a nut on the other side.

For some reason I'm seeing poor efficiency... 22Wh/mile. I think that's twice as much as I've seen mentioned on this board. I'll try turning off the brake in the ESC but it doesn't really feel like it's doing much anyway. I also noticed that one of the drive wheels is not spinning as easily as the other. Think it may be due to the 12T pulley... as it looks like it's wobbling a bit. I think I'll order a couple 13T pulleys and give those a shot.

Finally, one of the 5Ah Zippy packs I have has two lower capacity cells. They hit 3V when the other 6 are still at ~3.5V. Not sure if HK will warranty that or not but I put in an inquiry.

 

[psychotiller]

Not sure about others but I didn't like pneumatics or ultra big wheels on my setup. Ride can be bouncy at 15-20mph especially with potholes and obstacles. Obstacles you don't necessarily want to ride 15mph over them on a pneumatic board unless your strapped to it

Yeah, I have to disagree..My pneumatic is buttery smooth at 30mph. I know you were using those light weight tires though Torque. I went with the Matco tires instead. Hope we can all meet up someday to compare set ups.

 

[torqueboards]

Not sure about others but I didn't like pneumatics or ultra big wheels on my setup. Ride can be bouncy at 15-20mph especially with potholes and obstacles. Obstacles you don't necessarily want to ride 15mph over them on a pneumatic board unless your strapped to it

Yeah, I have to disagree..My pneumatic is buttery smooth at 30mph. I know you were using those light weight tires though Torque. I went with the Matco tires instead. Hope we can all meet up someday to compare set ups.

Hrmm.. Is your setup pretty bouncy? Guess, I should get those 2" wide tires then.

 

[psychotiller]

Not sure about others but I didn't like pneumatics or ultra big wheels on my setup. Ride can be bouncy at 15-20mph especially with potholes and obstacles. Obstacles you don't necessarily want to ride 15mph over them on a pneumatic board unless your strapped to it

Yeah, I have to disagree..My pneumatic is buttery smooth at 30mph. I know you were using those light weight tires though Torque. I went with the Matco tires instead. Hope we can all meet up someday to compare set ups.

Hrmm.. Is your setup pretty bouncy? Guess, I should get those 2" wide tires then.

My deck is a generic and has a little flex (I am weighing 210 right now so everything is a little flexy haha) I remember the wheels you have as feeling mushy and slow. These are a different ball game entirely. http://www.matcomfg.com/TIRETUBE6x24PRTUBE90DegSTEM-idv-3097-38.html

 

[made_in_the_alps_legacy]

How do people like the powered Onda board compared to regular longboard? ... Just curious what other people think.

I went back to skateboarding with the Onda Vibe, which is small, wide and has not too big wheels (140mm). while the ground clearance is very low, I appreciate that feeling to have my weight like "amoking" below the wheels axles. The wobbles I got were solved with a compromise on the shocks (I do ride black/red back and forth weighting 90kg). I see people suggesting that those boards are heavy : My e-Onda Vibe is 6.4kg...
Later on, I got an Onda Core, and an Onda Longa : I did not enjoy the taller wheels feeling my weight being too high, the Onda Core deck is narrower and stiffer than the Vibe, the Longa is the flexier deck of all 3. ...so my 1st onda is still my preferred one. I don't have a significant enought experience with regular longboard/skateboard, but I believe the Onda boards will remain a niche within a niche market.

 

[Wayno]

Here's a quick update on my build. The ESC issue was resolved by upgrading to a 12s capable one and now I can run it from full charge. I'm still have a small issue where one or the other won't arm immediately and I need to resolve that. With me on it and riding around at an average speed of 8mph efficiency worked out to 15.85Wh/mile which still seems on the high side. Surface was mixed asphalt and some nasty concrete. I have one pulley that has some curved teeth on it and there is some additional resistance due to that but with this setup I'm getting about 9.6 miles (GPS measurement) off of a full charge of the 8s 5Ah pack. I might have mentioned it earlier but one of the cells hits cut off voltage when the rest are around 3.5V. I did receive a replacement pack so that should improve range slightly also. Riding on asphalt is great but gaps in concrete are quite jarring.

My friend put on his safety gear and hit a speed of just over 25mph but stopped there since he thought it felt a bit unstable. This was with red/blue front and red/black rear (where motors are). I turned off reverse and set braking to 20% and now the ebrake is actually useful (just have to be ready for it at higher speeds). Turning off motor timing and setting start power to 30% has improved starts from standstill/low speed. I do not think that this is a very good board for higher speeds due to the truck pivot angle.

I'm contemplating if I still want to move the batteries below the deck or leave them on top where access is really easy. I'd like to have the flexibility to switch out the LiPos to an 18650 pack that I eventually will get together. Here are some photos.

 

[CSN]

Might want to try reversing the motor driving with the motor in front to see if its more stable. Some people have said it felt better and more natural.

It might help to get the batteries down to get the center of gravity lower.

The range is encouraging. I was expecting it have less range than a regular longboard.

 

[Wayno]

Might want to try reversing the motor driving with the motor in front to see if its more stable. Some people have said it felt better and more natural.

It might help to get the batteries down to get the center of gravity lower.

The range is encouraging. I was expecting it have less range than a regular longboard.

I tried that before but like it better this way. Every time I've seen the oscillation occur it was always on the side of the board with the motors, which is the heavier side. To make sure the chance of that happening is minimized I put the stiffer shocks there but to keep the turning radius reasonable I go with the softer shocks on the other end. This means that the axle w/o the motors can turn sharper than the side with motors. With the light end in front it feels more like a front steer car vs a rear-steer car which I believe to be more stable. Good suggestion though and I certainly would encourage everyone to try it both ways. I thought front drive would be better also.

If I was to do this again I would go with 1WD to keep costs, mass, and complication down. It was way more power than it needs or that I use right now. It should be possible to have one motor, with a long shaft, drive two wheels but without a differential tire wear might be an issue.