How about this 3 phase gearboxed motor?

[metalnwood]

Hi all, on and off I have thought about a motion platform for my sim.

This has been going on for a few years! I play different types of simulations, motor, combat and FSX.

I am primarily thinking of using this platform for GA/FSX flying rather then the other two. I want 3dof as I think heave is something I should have :)

Because I have some bigger machines at home I am lucky to have 3 phase so looking at 3 phase motors is an option for me.

I am I don't read too many posts about this option. Lots and lots of DC motors and 2dof platorms, Ideally I would like my platorm to support myself, one other and the sim. Lets say thats, 180kg of people and the rest is sim.. Dont know what that weighs in its final incarnation but lets say 320kg all up for everything or 705lb.


I am in New Zealand so importing isnt much of an option with our low dollar but I do have some 'cheap' options available to me locally.

E.g.

http://www.machine.co.nz/view_photos.php?b=29555

This is about $250USD for .75hp. For similar prices you can get up to ~1.5hp with speeds around 70, 100 and 300 rpm.


Now, I have read that constant change of direction is not good for these guys. Is this correct or are the motors I am looking at sufficiently 'industrial' to not be a problem?

The idea is to attach an arm to the spindle and lift the platform via that, and another rod of course. Pretty standard from what I have seen, simmotion.com as an example looks like 3phase motors and exactly the same as I have been thinking - and many others sell the same thing.

So are these motors up to the task or are there a few other things I am missing?

I guess that with these motors I would need the platform balanced? I guess they wont take the weight by themselves?

If I need it balanced will this restrict the maximum height I can go? I see for this vendor that ~10cm is all... perhaps thats ok as I have never experienced it..

Any thoughts appreciated.

Thanks,
Jason

[diegocn]

Hi metalnwood,

Sorry for my english.

Yes, the motors dont support the weight of the platform, you can use
a center post you spring or counter-balance to support the weight of
the platform.

The question is that it dont go 100% balanced, like the weight of
you and the other person can be different, some controls too,
etc... The platform in a high bank angle, considering the pivot point
in the bottom of the platform, will get more weight in one side,
generally in the side of the banking angle.

If you add heaven, then you need to balance this too. You can use
a spring or a counter-balance. With counter-balance you get like
linear force in all the course, and can add/remove the counter-balance
weight, if you modify the load.

For the actuators, in general the reductions cost more than the motor,
but you could do it with chain and sprocket.

The problem of using an arm, is that the force/velocity over the course
of actuation is not linear. You can do a linear actuator with chain and
sprocket too, this gives more speed compared to the common lead screw, and needs less reduction compared to the arm in the spindle, depending
on the motor of course.

You could use electric for the low force positioning and pneumatic for
assisting it.

Of course, various options exists, like hidro-pneumatic that gives speed, force
and good positioning, electro-pneumatic like I said, only pneumatic with proportional valves, etc...

Thanks,
Diego