Showroom My 3 DOF seat mover + GS-4 + Simvibe

What an awesome rig!

@Nick Moxley , any idea what the rpm of the motors you have?

What ever PGSaw's 25:1's are rated for......160-180 i think.

Thanks!

Yeah, I know some of you have had a big guy in your rigs as a one off for a short time and it seemed to cope but I will be using my rig all day, everyday so I have to design it to always be used by someone my size. Because the reduction in the 50:1 ratio gearboxes is so massive then you need that high motor RPM. The other 50:1 motors that use 3200RPM motors only spin the output shaft at 65RPM. My motors are almost double that at 110RPM on the output shaft. I want that extra speed on the output shaft and I want the extra torque of the 50:1 gearboxes. My motors have both of those attributes so it is the perfect motor for me. The weakness is the controller, the JRK's just aren't powerful enough to run the kind of motors I want to run. I think I am way better off trying to get a better controller working than downgrading to a slower motor.

It is like when I used to race IRL, I used to blow gearboxes because my motor was too powerful. Yes I could have put in a less powerful motor to save the gearboxes but that wouldn't have been good, so what I did was put in a stronger gearbox (A Ford Sierra type 9 5 speed) Then I had a fast motor and a bullet proof gearbox.

With my racing I found that building anything with a lot of power, you upgrade something then something else breaks because it can't handle the power. So you upgrade that, then you find a new weak link and replace that. The after awhile you have everything upgraded and it can handle the power.

This is exactly the same, the JRK's are the weak link and I just need to upgrade them.

If they are 160-180 at the output shaft with a 25:1 gearbox then they will be 4000-4500 at the motor.

To me the sabertooth would be the only option , higher amps for 12v or even 24v.
I have tested them with the K8055 and a couple of guys I know of successfully use it too with the sabertooth.
Maybe an option and I know the guys are working on making the Ard support it too.

Sorry I have been really slack at updating my build thread.

Since my last update I have added a new DSD shifter to my rig.



I also moved house the a couple of weeks ago so I used to as a good excuse to powder coat all the new parts of my rig.

I went for a gloss black and it looks so shiny now. It looks even better in person.

The powder coating wasn't very expensive and the results look amazing. I think I will be getting a lot more of my parts powder coated in the future.

Seat frame





DSD Shifter mount



Connecting rods



Lever arms



Main frame



Motor mounts

Thanks. Yeah, I am really impressed with how the powder coating turned out. It looks even better in person.

I really like the DSD shifter, It is really heavy duty and it has a very short hard throw to it so it suits the rest of my rig. It is quite a workout now with the AF plus the DSD pedals and shifter. I did some laps of the new Nords in AC today and my hands were killing me after a lap. So much fun though.

Now on to the reassembly.

Rubber isolation feet back on.



So shiny



The universal was painted instead of powder coated.



Universal back on



Seat and frame reattached.



Plywood electronics board painted.



Motors and electronics reconnected



Back half of the simulator fully reassembled

I got a new desk so I could move my monitors closer and have them at a 45 degrees angle.

My new house is much bigger so it means I have room to leave my rig permanently set up.

Everything all set up and running

@Avenga76
yes, your paint is gorgeous!
and your gaming room is desirable

I'm just wondering how you can press the Emergency button?

Matt, im 99% sure he has another mounted up within reach which driving.

lookin good Rich.

Hello all,

I've read through the whole thread, very interesting stuff!

Disclaimer: I have not finished my first motion sim so the below is full of assumptions that could be all wrong.

I believe your problem with over current is the high inductance of your motors. Those are probably not designed to be switched back and forth like that. With smaller motors we get away with it because the controllers overpower them. With larger motors like yours the controller has a hard time with instantaneous reversals. If you have the option to cut the PWM setting for reverse/stop, try that and it will work, albeit with slower response during high bumps. I had similar issues with my first 7"x3" (177mm x 76mm) motors. I swapped those for smaller but true servo motors and the problem is gone (on the bench, not in a rig yet).

I've done a couple 2x60A RoboClaws and burnt them to a crisp with the large motors mentioned above. In theory - and per manufacturer's claim - they can set motor position using potentiometers. But I tried to get this going for months and it just does not work. If you really wanted to use them, I suppose you can add an Arduino board to read the pots and send commands to the RoboClaws. I have one of those RoboClaws on a Segway clone and they work great.

Back to motor sizes, as a test, remove the rods from your gear, have someone sit in and pull/push them by hand. Shouldn't be too hard to move them around. You have a large lever up by your seat's shoulder. Your motors have tons of torque already and that is being multiplied many times over with your gearboxes. It shouldn't take 13.8V*70A = 966 Watts per motor to move someone. Most of that is being consumed by the motor itself during reversal, IMHO.

Regards,
JR

Thanks. @Nick Moxley is correct. I have another kill switch mounted next to my steering wheel as well a the one on the back. This means I always have one in easy reach.



I find the one at the back really good if I have visitors over trying my rig. I can stand behind my rig and quickly tap the rear kill switch with my foot if they do anything crazy like flip the car (that has happened )

Thanks Nick.

Hi JR, Thanks for your reply.

Yes, you are correct that it the motor reversal that was causing the problem.

This video here with the gearboxes detached shows the problem perfectly



The controllers can handle slow speed reversals fine, but once you start speeding up the motors you get those 70A spikes on reversal. If you leave the motors running in one direction, even at full speed then the currents are very low, it could run continuously all day like that without a single error.

In that video you can see that the errors only happen on motor reversal.

Since that video I have done a lot of tweaking and I have managed to solve the problem.

The biggest thing was to add a 20ms "brake duration" The JRK's allow you to add a pause before changing the motor direction. I think this give the motors a chance to spin down before reversing.

The 20ms pause isn't at all noticeable when you are driving and I am able to increase the duty cycles. So it feels much better with the brake duration added and it has solved the problem. This also allowed me to increase the intensity of the ride so now it can handle bumpy roads like a champ. I can go off track with out any fear of the errors happening.

Also when was rebuilding my rig I retested my pivot point. I got my brother to pull/push while I was in the seat and it took very little effort, I also tried it with him in the seat. I think the seat is really well balanced and the universal moves very freely.

In my early tests I ruled out anything mechanical with the arms, pivot, gearbox by removing the motor from the gearboxes, this made it clear to me that it was the motor reversal then after that it didn't take me long to come up with a setting that worked really well.

So yeah, I think the key points are that if you are going to run bigger motors like mine than limit the duty cycles and add a brake duration so the controllers can handle it.

I am now very happy with the motion I am getting out of the rig and getting no more motor errors. It took a bit of tuning but I got there in the end.

Interesting read @Avenga76 , yes it seems that faster RPM motors are the issue, but your knowledge and experimentation has show us how to get around it.
I know with my 4500 rpm motors on my converted actuators I had a similar problem, but I didnt have a scope to find out how much current they draw on stall on change of direction.
It seems motors under 4000 rpm rated at 200 watts run more than fine on the JRK.
anything about that rpm speed needs some fine adjustment of Settings in JRK utility.
@JRoque , your disclaimer is understood and thanks for the input.

Yes, I would say that would be a good rule of thumb. Anything under 4,000rpm are fine, anything above that will need some fine tuning. the faster the motor, the more tweaking you will have to do. Luckily the JRK's have a lot of ability to tweak the settings.

An awesome build thread and awesome sim rig.
Wonderful!!!

Thanks @Steve spenceley

Good to see you over on this forum.

Congrats on the new home and the permant rig Richard.

The new powdercoat looks really awesome
The entire rig has a very cool and tidy look. Great job

Thanks heaps!!

BTW. I am really impressed with your build. You did an amazing job fitting it in to such a small place. And you got it done super quick

Another quick update.

I ditched my old smart battery charger. It was a little too smart for it's on good. It would do silly things like try to boost to voltage up to 14.7V to quickly recharge the batteries and it would error out if the batteries dropped below 12.5v.

Just swapped it for a straight 13.8V 40A power supply. Seems to be running much better.