My new motion project. Help please.

[dualin]

Hi everybody, I´m from Spain and first of all, sorry for my poor english, I´ll do all that I can with the litlle help of Google translator.

I´ve found this forum and the old one 15-20 days ago, I´ve read a lot of post in both forums and other webs, and now I´m prepared to start my motion cockpit.

Here is my first design, without movent and with the microsoft wheel to play with the Xbox360.



This is now, with a litlle modification in the height of the seat and with the change of the wheel, now I´ve a Fanatec CSR wheel and CSR Elite pedals.






And now I want to convert it in a motion cockpit with the followings considerations:

About electronic, I´m going to use the AMC 1.5+H-bridge of TronicGR, I´ve buy it from an user of that forum.

Motors will be the wipers of a WV Golf III.

About the power supply, I doubt between a car battery or another power supply with a voltage of 14V. for less amperage.

The joint will be this one:



But I don´t know if I´ll have rotation problems, maybe I need a joint like this:



About movement, I want only to move the seat, not the wheel or the pedals, because my weight (100 kg) and I think that is the best for sensations like drive a car.

Then I think that I need to make an structure like this:





And I´ve made a handmade writing for the measurements





And here is my great doubt, Where should I put the pivot point and how far should I place wiper motors from that point.

Thanks in advance for your help


Best Regards
Dualin

[motiondave]

Hello from the pictures, a universal joint would be better to stop rotation. A steering knuckle or a cut down driveshaft would do it. No specific model car, just cheap and second hand.
For power supply, use a power supply and battery in parallel. It gives you plenty of power without the need for expensive power supplies.
As you weight is 100kg and you plan to use wipers, I would suggest you mount the motor connection levers at the shoulders, not at the back. Yes it makes the frame longer at the back, but it gives you the leverage.
I have built sims with motors under the back like yours. I found its a good setup, but not really for a driver 100kg plus. But judging from your drawing, if you space the motors about 200mm or more back of the seat frame, you may be OK. But if you do that, consider a shoulder mount setup.
The pivot point is under the best place of balance. In this case, sit in the seat, run a straight edge across your belly button, draw a line down from that point , and that's about it. You may have to move the pivot point back or forward a bit to find the best balance.
For control boards, consider the Pololu JRK http://www.pololu.com/catalog/product/1393 , easy to setup, one per motor, 7 wires and one usb cable per motor.
http://www.youtube.com/watch?v=rb5tK4oMQy8 heres a video of setting up jrks in x-sim.
Hope that help.
Cheers, David.

[dualin]

Hi David, thanks for your fast answer, I don't want to put the connection levers at shoulders, because when I keep the cockpit, I put it under a table and I can only keep it there. I don't mind if the frame is longer, but I need that keep the cockpit under the table.

I've bought the electronic yet, amc 1.5 and h-bridge and I'll have them in two or three days.

I'll think about the rest of your post and will write later.

Best regards
Dualin

[dualin]

Hi David, I'm thinking about the situation of the motors. How many cms must I separe the motors from the pivot point?.

About the power supply, can I use a battery charger? Or better a CPU power supply? CPU power supply about 500 W?. How many Amperes must be the battery?

About the electronic as I said before I've bought an AMC 1.5 and a H-bridge (tronic design) from an user of this forum last week, and I hope that arrives to my home in two days.

Now I'm investigating about the pots, I think that the best is 10k potentiometers, 270 degrees.

Best regards
Dualin

[motiondave]

Ok, I looked at you drawing again, I can see you have left a "?" on the measurements. At the back of the seat frame, if you can space the motors as far as possible, it will help for leverage. The only other thing I can suggest is reach the frame froward so the motors lever at the front as a seat mover. This would allow you some compact design.
I did this with a "frex", but levering the motors near my feet. It allows me to move over 120kg ( I am 80kg), but I am using powerful worm gear motors.
A CPU power supply should do it, of it puts out enough current. Remember the motors rum on stall current, which is higher than rated. One reason I use a battery in parallel, mind you , I use near 70 amps + in spikes.
A battery from 300 CCA should be enough , even with a car charger on it.

Good to see you have sorted electronics, check with tronic as to what pot to use.

[Bruceaust]

I found these on ebay,

10K 5 turn pots .JPG (21.12 KiB) Viewed 30996 times

http://www.ebay.com.au/itm/320925459304 ... 1439.l2649

They are 10k 5turn pots (not 3turn as advertised)
I cannot vouch for their quality but they are certainly cheap!
I will give them a try.

[motiondave]

That will work, but you need to find plastic gears to turn them correctly. Have a dig through a local hobby shop or two and yo may find something.

[dualin]

Hi, I've my wipers now, are from a wv golf 3. Here is:



I've tried with a car battery and works well, but I'm not sure what must I do with the cables. There are only two cable, green and red in the connector of the wiper. There is other pin that connects to ground, to the body of the wiper. If I connect battery+ to red cable and battery- to ground, the wiper works in one direction, if I connect the cables changing the polarity, the wiper works in the other direction, but if cut the connection with the body of the wiper, I connect the same that before but now the wiper doesn't work. And a few minutes ago I've read in the bosh page the caracterIstics of the wiper and I can see that I must to connect the battery to the cables red/green for works in one or another direction. I dare to try to connect red/green cables directly to the +/- of the car battery because I don't want to damage the wipers

Here is the caracterIstics:

Bosh CHP 12V 42W
Nominal voltage UN 12 V
Nominal power PN 42 W
Nominal current IN 9,4 A 
Maximum current Imax 45 A
Nominal speed nN 135 min-1
Nominal torque MN 3 Nm
Breakaway torque MA 17,5 Nm 
Reduction i 52 : 2 
Direction of rotation L/R 
Type of duty S 1 
Degree of protection IP 23 
Weight approx. 1,10 kg 
Similar part number 0 390 251 684 
Clockwise (+) to green, (-) to brown 
Anti-clockwise (+) to brown, (-) to green 

How must I connect the cables? Is is wiper a good wiper for my project?

Thanks in advance

Best regards
Dualin

[dualin]

Hi, after a few days of hard work, I´m back again with news about my project. The electronic arrives at my home, the Tronic AMC 1.5 and the Dual bridge 1.2.




Now I´ve connected the AMC to my CPU with a USB-RS232 converter and make it work with X-sim 3.06 aluminium and Rfactor, but the Dual bridge doesn´t work. I´ve read a lot of post and I think that the problem is the mosfets, because it has IRFZ44 ones instead IRLZ44N as TronicGR says in his post. I´m going to buy the correct ones and try. I hope that I can fix it.

About the wipers it´s all right now, because I found the cable to ground that I must to cut. Then the wipers works fine connected directly to a car battery.

I have also connected the potentiometers to AMC and works fine too with the xSimCTRL (I´ve installed the alternative firmware for the AMC board).

About the frame I´ve decided to mount the motor connection levers at the shoulders, but I´m thinking about make it folding. I have one or two ideas, but I will here when I have a little more clear.

What do you think about the specs of the wipers??, are enought for my project?

Best regards
Dualin

[motiondave]

the wipers look fine, but really tronic should be advising on this as you are using his boards.