Trying to build a 2 DOF Rig

I'm starting to search and buy the motors, but I will start with a static rig, then go to 2DOF and finally add the 3rd DOF in the form of traction loss.

Hope to see your progress on adding the 3rd DOF, please keep us updated on your progress,.

Thanks again for taking the time to explain all the details.

Hi @Frantik,
Found a guy that might get me the motors, 2 from a prius and another from a Renault.
Could you tell me what kind of power supplies you are using for the motors?

Thanks,
LP

Hi Luis.
I used this one from Amazon.
https://a.co/d/iWfAIg5

I haven’t test the watts draw yet from both motors. I’ve been meaning to do so to check it can have enough supply to run 3.
I assumed 150watts each draw based of Dave testing his wheelchair motors.
I’ve got a meter. I should test them to know exactly.
I haven’t yet installed fuses too….

My blower fan for wind simulator is 10amp too.
It would be great if I could drive all 3 motors and the blower of the one power supply.

I might get my hand on 2 of the 3 motors to test things out still today (1 Renault and 1 Toyota) the auto parts seller is a racer (of real cars, not virtual) and he will let me borrow the steering columns for a week to see if they can do what I need.

The Renault motor is almost half the price (75 € vs 130 €), Renault is a best seller here, so it's normal that there are many more wrecks with Renault cars than any other brand, but I'm unable to get any specs on them. I still tried to find Toyota Prius steering columns but those cars are a bit rare in Portugal, so, no luck getting one exactly like yours.

Sorry for asking so many questions, but you removed the shaft\column from the electric motor, was any cutting involved or just some unscrewing?

To test the motor, I made a quick order from amazon for a controller and as5600 and diametrically polarized magnets (I read some reviews that the ones that come with the as5600 that I ordered are not polarized correctly) - a friend of mine will borrow me an Arduino Uno r3. Do you think a power supply from a PC will be able to supply enough juice?

Do you know of any test I can do to the motors to find out their torque, speed, etc?
Or any site that contains data specs for each motor.

Thanks again for taking the time for helping me out.

Best Regards,
LP

Hi Luis. I’m sure Renault is just as capable as the Prius motors. The Renault fuse recommendation will indicate how powerful it is.
I had to cut down the long end of shaft with angle grinder. I left about 1” proud above the worm gear housing in order to fit the magnets. But the diametrical magnets won’t require as much I guess. Cut its height with consideration of how you’re mounting the as5600.

The pc provides power via usb to the Arduino and as5600 is 5v supply via Arduino pin out.
from that you should be able to test the as5600 with simtools. Note there is documentation on how to run 0-5volts, default is 0-3volts on as5600. I think we need to remove a resistor on the board… I’ll be figuring that all out very soon.
Later the motors can be tested with power supply. But I’m sure they’ll be more than enough like mine. take a photo of the Renault motors. I’m curious. I think more important is it ease of installing. Prius was so simple to bolt and fit lever with the factory spline and bolt location

fyi the Corolla motors looked more difficult to fit because of bolt location but the worm gear is enormous so think it will perform better than the Prius units.

Hi Frantik,
I was amazed about the size of both motors, I was expecting something smaller.
From the online information, the twingo, power steering fuses are 10, 15 (depending on the model 1 to 2 of the Twingo - https://fuseandrelay.com/renault/twingo.html), so 120 W (from the model of the motor, it seems more likely to be this one) or 180 W. There is also a 30 A identified in this page: https://knigaproavto.ru/shemy/en/renault/twingo/495-2000-2004-renault-twingo-i-fuse-box-diagram.html, that would give a 360 W. If you have any hints about what amperage I should consider, I would appreciate.

And for the Toyota Auris, I see 2 fuses related to power steering, one with 10 A and another with 60 A, but related to EPS the value is 60 A, so, about 720 (https://fuseandrelay.com/toyota/auris.html).

Renault Twingo





edit: sorry for the fuzzy picture, it's a different view showing support at a motor level and at the shaft level



Toyota Auris





Did your Toyota motor had this metal tube around the shaft? (edit2: this motor seems very similar to the one you posted of the Corolla)

Sorry again for the number of questions, for me it's a substancial investment, thanks again for sharing your experience and for all the help.

Is I can take more photos to help, just let me know.

Hi Luis. I’d say it’s the 30A. The 10a fuse is probably for the steering controller module?

as far as amps is concerned, surely more is better. Knowing that 30-60watt wiper motors struggle to move these motion simulators.
According to one of Dave’s videos his 3dof rig pulls 25amp peak on 12v which is 300w combined. So even the twingo should be plenty enough grunt.

yes mine did have the metal tube too. Removed it and cut the shaft length down. That’s the sensor end. You could kept the tube and just shorten it and used it to mount the as5600 to?

btw that Toyota auris looks the same as the Corolla one I’ve bought for my 3rd dof.
I should check the receipt… maybe it’s the same. I think it will be better with that huge worm gear.

I bet there is a massive range of suitable power steering motors waiting at any local wreckers.
The only downside I see so far with the Prius motor is some free float in the gear. Unless that’s in the simtools software… there’s about 2-5deg float before resistance. If it’s in the gear it makes sense that the auris/Corolla would be better given the gear diameter is bigger and should translate to less deg float. It could also just be ware and tear from mileage too. I’m still unsure if it’s software or worm gear related.

Did the twingo motors come attached with a spline fit UV joint? You’ll want that to easily make the lever arm.

Good call, the 10A must be for the controller board, not the hardware.

Yes, you are right 300 W should do the trick.

I think I will try to buy 2 Renault motors to start the build.
- My budget for motors is 200€ (I will still try to lower the price from 75 € to something like 60 and buy 3)
- Electronics are cheap (< 40 € if I buy an Arduino clone), PC power supply if it has enough amps or buy the power supply that you bought
- Seat is around 50 € if I don't build it myself or get one for free
- Wood and screws (I hope to spend less than 150 €)
- 4 female ball joints and rods (no idea of the cost)
- UV joint (I will try to get one from the wrecker for free or at a low price)

I will have to find a way to buy the lever that fits the shaft, I don't have any tools to solder that kind of material.

You were able to just pull out the metal tube around the shaft? (I won't do it now, since I don't own the motors just yet)

I will check if the metal shaft is soft enough to cut with the tools that I've.
But it seems like a good idea to keep the metal tube for an as5600 casing, especially if I'm able to get a metal lead to match the look.

The advantage of buying the Toyota one is that it seems massive and more powerful, and you are already using it, so I know it works but it costs a lot more than the Renault one (75 to 130) and it blows my motor budget.

Regarding the free float, can it be just dirt in gear? I saw a guy on youtube, opening one open and giving it a good scrub.

No UV joint on the Renault columns, if I end up just buying Renault motors, I will buy the joint separately.

Hi Luis.
For reference I paid 85-100nzd per motor which is about 50-65usd I think.

Regarding lever. Although I can weld and have welder. I just had the engineer at work weld bar onto the 1/2 cut uv joint. It’s a 5m job so shouldn’t cost much if you have the spline uv end.

I doubt the float is dirt. More than likely float built in or due to hi miles.
But I’m also thinking it’s software related. The hall sensor registers the float but the dc motor doesn’t respond to that slop. If it is software related it’s then compounded by the fact my diy hall only registered 1-4v over 180deg vs 0-5v effectively making it twice as pronounced.
I guess I’ll see if there’s improvements once the as5600 is programmed at 180deg and installed

Regarding ball joints. I got 10mm females from this supplier on aliexpress.
Quality and freight time was good.
https://a.aliexpress.com/_mL4R1ro
I ordered model SI 10TK

Only after your description, I was able to identify half of the uv joint , that is a good hint.
Thanks for the source.
Do you know the amount of time I searched for the name of that piece (ball joint)? I didn't even knew the name of the ball point in my native language.

Thanks again for all the help, hope to get things tested this week (electronics), and then start buying the building material after having the seat and the motors.

When you start working with the AS5600 or the 3rd DOF, please update this

Hi there, since I don't have the electronics I tried to test the Renault motor. Since I still haven't bought it, I pull out a 600w PSU from an old PC, connected the +12 and the ground to the motor (still using the connector that came with the motor), simulated the power button of a motherboard and I can hear the motor running (I can also feel some moving parts) but the shaft doesn't move.
Without opening the motor, can you think of a way to check what is happening?
Do you have any way to check if the motor is 12 or 24 v?
That connector in the motor has 2 thick hires (one black and another red) and two thin wires (both are black), I only connect to the red and black, do you think there is a need to connect any other wire?

Thank

They moved my last questions to this new post, it seems I was taking over your discussion, sorry @Frantik.

I connected the PC power supply and I wasn't able to get the shaft moving
But I received some of the electronics and a colleague was nice enough to lend me one of his Arduino boards.
So, today I was able to test as5600, it was a very manual test, holding the magnets with a toothpick and getting values from 10 to 336º, I didn't even solder the wires to the AS5600 board.

It was my 1st try at Arduino, so, I'm happy with it
I used the https://github.com/Seeed-Studio/Seeed_Arduino_AS5600 lib.

On Friday I will go to the 2nd hand part store and check if the motor is broken or the power supply was not enough (voltage or power (amps)).

Best Regards,
LP

hi Luis. Sorry the late reply. I too started working on the as5600.
Just researching. It appears we may need to remove R4 resistor to get 0-5v analog output. I’m still researching the i2c 180geg angle programming. Perhaps the library you suggest is a good place to start.

the problem you’re having with the motor is probably power supply. Maybe the power supply needs a trigger? I think on motherboard there is a some type of jumper? That’s required to power up the psu. I seem to recall there being something like that. I built a mining rig several years ago that used two psu. The second psu needed a jumper to power up.

I assume you’re powering the motor with a combination of outputs? You’ll probably have to combine 6pin sata and 8pin vga outlets to not exceed the amp loads on each plugs at 300w each motor. Do some math on load limit of each cable to know what’s required to power your motors

Hi @Frantik,
That was my 1st thought, the power supply is not powerful enough, so, my 2nd test of these motors was with a battery from a car and the output was the same, some noise from the motor, but no movement on the shaft.

After 3 days, with the permission of the motor owner, I carefully separated the motor part from the gear and the motor seems to have no torque whatsoever.
Just by placing a finger on top of the rotating motor, it stops.

I tried 2 power supplies, an old 450 w (I think the max wattage was around 30 or 40A) and one 630 w power supply from Thermaltake, where the +12 V is able to deliver 65A amp (630W power supply supporting peaks of 700w), I combined the +12v rails from 2x GPU (one from each output) and main ATX, it still didn't work.

I even tried to input a +5v~0v square wave from the Arduino at different frequencies into the control to see if it would "unlock" something. I will return the motors today to the parts vendor.

But I will try again, either with motors similar to yours (try to get them under 100€) or wheelchair motors.
Not quitting

Regarding your build, can you explain why to need 0 to 5v range?

Thanks for all the details in your reply,
LP

Hi Lius. We need 0-5V analog signal on the potentiometer/as5600. the simtools software is expecting that range. 0-5v min to max stroke and 2.5v central stroke. there may be a simple way to alter the code though for 0-3v. i think removing a resistor is easy nenough especially since the as5600 is designed to operate both options. defualt being 3v and removal of R4 giving 5v

Thanks for the explanation, I thought you could define the range as a parameter.

I bought some extra units, have to try that procedure

R4 was incorrect. i think its R1 that needs removal.
R4 is pull down resistor required for manual programming.
Couldn't successfully burn the 180deg range yet. working on it.

https://github.com/Seeed-Studio/Seeed_Arduino_AS5600/blob/master/README.md

I suppose you were following this (https://github.com/Seeed-Studio/Seeed_Arduino_AS5600/blob/master/README.md):



You can test by shunting the top and bottom before removing