David's PSYCHOFRAME

DavidC · January 16, 2022, 7:30pm

Some of the posts and picts here are already in thread “PSYCHOFRAME by ETOXX aka NOWIND”. I thought it was more relevant to create another thread rather than hijacking his thread.

This psychoframe is amazing!

Finding all the parts needed to build it is just part of the fun!

This quest takes you to discover karting spare parts sites in particular, which opens up new horizons in the field of electric skateboarding.

Jens Keppel De Vinci is a genius. I spent so much time watching this psychoframe from all angles. Everything is so smart and so beautiful at the same time.

But to prove that beauty is not the goal of this creation, he puts you an old military box of ammunition on top of it. The icing on the cake!

This machine is made to be devastated in dust and stones, not to remain immaculate.

Jens is still available by Signal and email. He even gives his phone number. Fortunately he has sold only one so far . It’s very practical to move forward when you’re stuck on a trifle.

So I finished assembling the whole chassis. It is thought to be quite simple. I just had a few problems fitting the ROCKSHOX spacers into the shocks. Tolerance problems linked to these spacers from ROCKSHOX. I had to file one inside because it didn’t move freely around the rod. Jens had the same “concern” for one in four.

It’s really nice how the shocks feel, it’s very different from the flex of our wood or composite decks.

For the motors, I ordered them directly from QS MOTOR. You can no longer order for more than 150 EUR on Aliexpress when you do not have a VAT number, in Europe. I contacted Harry Zhou (sales@qsmotor.com). The price: 2000W Mid Drive Motor: USD190.00 / pc. Shipping to France: USD215.00 for the two motors.

Both motors were shipped at the same time by UPS, but so far I have only received one fairly quickly a week ago. The second remains “On the Way”. It worries me a bit, but not UPS …

I manage to carry the complete frame quite easily with the four wheels mounted. It’s not that heavy and the honeycomb platforms make it easy to grip. We will have to see if it remains “portable” with the two motors of 8 kg each, but two can do it. I think to separate the box of ammunition with the batteries and the VESCs for transport and storage.

I ordered 5 Lipos Tattu 4S 22000mAh 30C from GenAce.de to supply two VESC 100/250 from Trampa with 20S. I did not find a Lipo 6S 22000m1h in 30C, but I should perhaps have gone directly to 22S (the limit of these VESCs, counting the spikes). Jens already has motor sprockets available for this voltage. The motors are rated 72V and I am already a little beyond in 20S. But given the size of the machines it would surprise me that they could not take more.

Thanks Jens for making such beauties available for us! The two years old kid loves it too and tried to help with his plastic tools

9

DavidC · January 16, 2022, 7:38pm

Then I had to replace AS150 by Jeti AFC 8mm Anti-Spark Connectors because AS150 gets blown at 20S.

I also have an issue with a TATTU Lipo 4S 22000mAh 30C that takes twice the time to balance compared to the 4 other packs, in spite of a correct resistance (3 mOhms versus 2), with no support from GENACE.DE that doesn’t answer…

DavidC · January 16, 2022, 8:03pm

Today is the day, first ride!

Getting the +60kg monster out of my living room was difficult because it’s larger than the door!

But it was worth the effort !

First impressions : it’s really great!! It’s not made for road obviously but locked diff is just what I need off-road. I didn’t expect turning would be so easy, even on road. You can go anywhere!

VESC settings :

20S
FOC sensored
Motor & Battery Current Max 235 amps (twice the value gotten by VESC-Tool FOC detection)
Motor & Battery Currend Max Brake/Regen -117 amps
Absolute Maximum Current : 420 amps.

A piece of video, not very great sorry :

Metr Pro log :

Speed is not true because I’ve mistaken the gear ratio value.

I’ve had faults. I don’t understand very well, cause there is written 4 in red but only 1 ABS_OVER_CURRENT has been recorded… And 420 amps is my absolute max value so why 383.8 were too much?

exx · January 16, 2022, 8:42pm

Very cool!
I always wondered if there was someone else buying that mad machine

PixelatedPolyeurthan · January 17, 2022, 9:34am

A fucking masterpiece. It’s literally a portable quad at this point. What’s the estimated range?

glyphiks · January 17, 2022, 10:27am

Holy shit, the consumption

I’ve had abs overcurrent from cogging of the motors before. Did you notice any cogging at all?

Creavenger · January 17, 2022, 10:40am

That’s amazing consumption is insane indeed compared to our “toy” boards
What would you estimate the range at?

davidbonde · January 17, 2022, 10:46am

Thats beyond anything else. Love the handle for your heel side turns

mr.shiteside · January 17, 2022, 12:59pm

I think because the speed is wrong then the consumption is also wrong. Eg the board thinks it’s only travelled half the real distance but knows how much energy it put out, so the consumption per km would be doubled

Andy87 · January 17, 2022, 5:44pm

Very nice write up!
Super interesting to see how you put that beast together and which troubles you had to overcome.

ABS over current can be caused by many reasons. If it’s coming from the motors, it helps to rise up the Absolute max current value a bit, but I think in your case that’s already pretty maxed out.
Other source could be some lose plug/connection or bad solder joint.
There are other sources, but those are the two most common I think.

DavidC · January 17, 2022, 9:30pm

As @mr.shiteside said I think Wh/km is not correct, neither speed nor distance, because set gear ratio is wrong. I mean it’s a two stage gear reduction and I don’t know what to set as motor sprocket et wheel sprocket to make calculations true.

But at 20S 22000mAh range is good : more than 45 min of fun, and my legs are dead! Ride ended with about 3.90-3.92 V/cell.

I didn’t feel anything strange when riding. I can’t remember what I was doing when getting this ABS_OVER_CURRENT. Maybe that was when I put front drivetrain into a trench and tried to get out of it going reverse. But I can’t see so much amps (352 or 384) anywhere when looking at the curves on Metr logs. I’m a bit concerned because as @Andy87 stated (thank you!) I’ve read some bad connections or bad solder joints can be involved in this kind of error. But in that case I think I’d get more that one. I can not set Absolute Max Current higher (420 amps) unless I use no limit firmware. Jens told me his settings with VESC 75/300 : “Vesc is set to 300amps on motor and battery , absolute max is around 500amps”.

Does anybody know why in Metr app 4 is written in red in records but only 1 fault has been recorded?

When I ride big bumps it’s the handle that keeps me alive! When I turn heel side, the white part between my trousers and my hoodie is not a piece of shirt it’s my ass Wife told me but I didn’t want to believe her until I see the video.

mr.shiteside · January 17, 2022, 9:42pm

Forgive the handwriting but I think this is right for gear ratio. The two stages are in series, so you can express them as fractions and multiply them together. 8:33 should give you an accurate speed reading, if you put in the right wheel size

I got the tooth count from the original post

TheRef · January 17, 2022, 11:02pm

Alright…. How did you talk your wife into letting you buy this?

DavidC · January 17, 2022, 11:11pm

I didn’t tell her before… No possible other way.

Thanks. So false entered gear ratio value was 10/59. Wheel size was set correctly : 29 cm (actually not really accurate because it’s 27.94 cm). Corrected values with GR 8/33 are :

top speed : 31.5 km/h ;
distance : 6,06 km ;
consumption : 88.7 Wh/km.

mr.shiteside · January 17, 2022, 11:19pm

There’s a chance I’m still wrong because the small gear in the second stage is hidden in the back a bit, but those numbers look roughly right now. Seriously cool machine, I’m very happy people (ok, person) have bought them

Creavenger · January 18, 2022, 9:55am

45 min is plenty for a beast like that

Titoxd1000 · January 20, 2022, 7:52pm

That Wh/km is not as good as I thought it would be with the qs motors. I build a go kart with 4x 6384 motors for reference and the consumption is about 70 Wh/mi. I thought that was bad and that’s roughly twice the efficiency if I converted the units correctly… I had planned to make another go kart with two of the qs1000 motors but I may rethink that since range and efficiency are a big consideration… How does the power feel like?

DavidC · January 22, 2022, 11:22pm

But I’m not sure entered gear ratio is correct. According to my latest Metr log with 8/33, calculated speed and GPS speed do not match at all.

Actually, first stage is 12/22 and second stage is 8/12 : global gear ratio is (12/22)*(8/12) = 8/22 = 0.36363636363 ???

I’ve been kicked off this place. It’s considered as “natural area” and it’s expected that grass comes back.

I’ve found another place where there are several rainwater retention basins. It’s amazing they are like bowls for psychoframe.

Il couldn’t record footage there…

I have fallen there. My back just slept on the grass it was not painful. It was easier than expected to stand up again on the beast. Thanks to the handle. I didn’t see my phone got out of my pocket so I needed to come back later to find it.

Titoxd1000 · January 23, 2022, 4:21am

The numbers are flipped in you division…2.75:1 would be the final gear ratio or 22/8. Interested to see what metr logs look like once this is corrected.

Pickled_Monkey · January 23, 2022, 12:54pm

^this, would 100% be interesting to know the real wh/mi