RaguTom's Build - 6DOF on a budget!

no :-( still haven't bought the new motors yet.

Are you using your simulator with those "old" motors right now? Or is the whole project on hold? I am also planning on exactly a similar design but with a higher lever point regarding to the seat/platform itself. So my motors would technically require less torque that way I believe. Anyways thanks for the update on this

UPDATE: I can't believe how fast time moves.... I have finally gotten some time back to devote to this project again. I have ordered the new motors. They should be here within the next month.

@Rens It was on hold for a long time. The platform has a decent amount of dust on it.

Some helpful tips:

1. Your levers give you an easy way to manage your torque to speed ratio. Make levers with multiple bolt holes so you can dial it in. The math gets you close, but there are too many outside variables to get it perfect in one shot.
2. Lower torque motors MUST be compensated with dampening and weight offset. I used tailgate gas struts to cancel out the weight of the human sitting in the seat. At that point the motors only needed to lift the top hexagon and cockpit. Unfortunately, this only goes so far.
3. SO you ask... why new motors then.... I spec'ed this project using wheelchair motors that we had laying around. The ratio was not for this project. The motors were about 60 rpm or so. The biggest reason was the back-drive. The weight of the platform alone would cause the unpowered motors to be driven to the ground just sitting idle. This would actually cause the platform to tilt massively forward. That is when the struts were added. Since the struts are independent from each other, one strut would push all the way up while one would fall. So the problem of "driving the motors without power" worsened with struts. Struts DID make the powered motors lift much easier.
4. The solution to 3 is to use self-locking motors. The wheelchair motors, being 60RPM (30:1 ratio) and electronic locking (emergency brakes) could easily be moved by hand, pushing on the levers. The new motors are 18RPM (100:1 ratio) and are self-locking, which offers no movement when the levers are pushed on.
5. The part number for these new motors is 5D300GD-RV40. I have one for testing and now five more on the way. Compared to the SCN6 specs: They are between $120 to $200 vs $600 a piece. Even at 18RPM with an 8 inch lever, they are 3-5 times faster than then SCN6. They can lift 10 times more than the highest torque SCN6. It was entirely a no brainer. Not BASHING the SCN6, but since it is the most common linear to use for 6DOF setups, it is worthy of comparison. I hardly classify the SCN6 as part of a budget build, so they were always out of the question for this project.

I hope to have a whole write up, pictures, schematics, and parts list someday soon. Hopefully it isn't another 4 years.....

Tom