Hello, diy future 3dof with bldc motors

Hello everyone,
I'm 49 years old, I live in Switzerland, and I speak English very badly (thanks google translate) and I dreamed for a long time of making an air simulator. I also wish it to adapt to car racing.
a few years ago, I had already thought about solutions, but I was stuck on one point: how to interface the game with the engines ...
a few months ago, while doing some research, i came across xsim, then simtools. as i saw that simtools could connect to an arduino, i bought a simtools license for testing.
I use arduinos for quite some time, I did a lot of tools with (2X 3D printers, a laser cutter, a engraver ...)
So I went on the idea simtools + arduino + htc vive.
for engines, I made my calculations: I was able to buy a used bucket seat (good deal with the rally drivers, who have to change their equipment often because of the changes of regulation: 50 € the seat with harness 3 points)
I then calculated the structure taking into account the stiffness of materials: I will use steel because it is easy to weld.
after calculating my structure, I was able to calculate the total weight: steel + seat + driver + accessories.
At this point, I calculated the necessary power of the engines. I based myself, for budget issues on a 3Dof.
the minimum power for my engines was to be 350W.
I found brushless 400W motors in 48V and fast switching controllers that can be very easily controlled by arduino.
so I ordered a motor + controller to test.
the motor is mounted on an NMRV40 with a reduction of 50: 1 and is powered by a 48v / 600W block.
I will give you the prices and references and photos in a future message.
I did tests with an engine: it reacts very well.
so I bought the steel bars, and I ordered the rest of the motors / controllers / reducers / power supplies.
I will receive all this in a few weeks. I will begin the manufacture of the chassis when the temperature will go up (it is cold and it snows, so I avoid going to work in my workshop)
more soon!

Interesting subject which open a lot of question :

Which type of Brushless motor do you want to use exactly for be compatible with this type of reductor?
And what about controllers for brushless motor easily usable with arduino ?
What type of communication protocol do you plane to use to connect arduino with controller?

hello,
the motors are bldc : brushless dc, 48V, 400W, 3000 rpm, 1.25N.m.
ref is: J60BLS140-430A
price: €50 + €40 shipping. if you order 3, shipping are €75 (for europe)
the size of motor is the same of Nema 24: it's frame 60, the axis is 14mm keyed

i put it on NMRV040, for nema 24, with 50:1: input 10mm keyed, and perfect fit for fix it.
ouput are 18mm keyed, single axis. i changed the single axis by double axis.
price: €35 + €39 shipping ( or €106 shipping for 3 units)


controller is DC10/50DPW30BL: it's a 600w , 48V capable controller. i use it in pwm /5v mode and 1 wire for dir.
price: €66 + 8€shipping (€44 for 3.... i ordered one by one ! )


and ... I do not plan to test: I have already tested with a complete set motor+reductor+controller: good speed, big torque !
so I ordered 2 more sets

when the snow is gone I will start the assembly and put some pictures or videos


ha, I forgot: the prices I gave come from aliexpress, but I think we also find on ebay or other: it is Chinese material

Well done !
I was looking for BLDC motor solution but I did'nt catch this type of motor!
I tried Geared brushless sensored motor wheel with lot less torque but your solution seems pretty good ! I ask my self if I can't change my point of view for one of my DOF.
I didn't know your controller. But I prefere open source controleur with numerique communication way, a bit more expensive but I think best way to avoid noise on set point?!
Do you planed to control your motor in torque (current control) or in speed (speed control)?
Do you already tried to interface/play with arduino and simtools (not needed to go at your cold workshop for that :-D)

I tested with the game "live for speed" (I do not have the plugins for other games yet), and it seems very well react.
but beware: I did the test with only 1 engine, empty ... when I try to force on the reducer, there is less vibration noise. I also noticed that by connecting the outside of the engine to the ground, it oscillates less when it is waiting.

for control, on the controller there are several settings. at the speed level, I put the max, I removed the startup delay, so in fact it is managed by the current.

I get a result that seems to match the game: slow movements or fast, everything looks perfect. remains to see once on the chassis

Ok, nice inital works, it look great !

Current control seems a good solution!
What do you plane to use as feedback sensor ?
For me, I did not catch some nuance on feedback. Maybe do you already understand that ? :
Angular position or acceleration feedback for Closed-loop control?

for the feedback, I use a linear potentiometer of 100k / 10 turns. I fixed a 10 tooth gear on the potentiometer, because I managed to find potentiometers and gears (always on aliexpress), with the same diameters of axis.

On the output shaft of the reducer, I fixed a toothed gear 30 teeth that I modified: I found wheels with a 19mm axis, I removed the fixation by original screw, and i dug a key. everything is connected by a belt.

so for 120 degrees on the motor, I have 360 degrees on the potentiometer.
it is therefore a feedback by angle. the potentiometer is connected directly to the arduino. I saw that it was better to have a shielded cable, with the shield connected to the mass of the arduino.
I take the 5v for the potentiometer on the arduino.
the arduino therefore receives a voltage (the potentiometer acts as a divider bridge): at 2.5v, it is in the basic position.

for the original setting, just put the potentiometer in the middle and reducer in the starting position, then install the belt.

the maximum position and the minimum position are then set in the software.

I still have to test with other gears to see if the accuracy is better, but I have not yet received the gears and belts I ordered.

I used this feedback system because it is simple, and the engines I use do not have built-in feedback.

there are 3 wires to turn, and 5 wires for hall sensors, which allow the controller to check the speed and direction of rotation. I do not know if we can use this for feedback, but it seems complicated, while the system by potetiometer is very simple.

I will try to make a photo as soon as I look at how to put a picture on the forum.

here is some pictures:

Take a look at my project, I use the internal hall sensors to calculate position.
https://www.xsimulator.net/community/threads/flypt-6dof-brushless-diy-actuators.10799/

Hello Ranch,

Thank you for your pictures.
I have a question for you : Do you think you can use this reductor in all position ?
Some manufacturer said that there gear worms reducteur must be used preferably at the horizontal (for best life with lubrification)... Do you have more detail about that ?
Does the lubrication is supply with reductor ?

there is no indication of the position.
the gearbox is delivered empty: it must be put gearbox oil, which is easily found in auto parts stores

it's ok, with lfs. very good speed


i must clean the room and install other games with my htc vive