building rotating platform

[zoloftking]

Looking for help in building a platform that elevates and rotates at the same time.  can't figure out how to approach it.  Thanks in advance.

[howitzer]

A lot depends on how heavy load it must be able to lift, and also the ratio of elevation and rotation.

Easiest way to build it would probably be to separate the lifting and the rotation so that there's a platform which rotates and on top where the lifting part is built on. It could be a scissor-lift driven by a linear actuator with driving axle routed through a turntable or something along those lines.

 

[zoloftking]

I tried that.  the rotating and lifting part seperately are straightforward.  I just can't figure out how same driver can be routed to drive both the turntable and the lifting, esp the lifting part

[Mr Jos]

A rotating platform that gets elevated and has 2 more independent movements possible;

XL Lifting arm with multiple spinning functions. - LEGO Technic, Mindstorms, Model Team and Scale Modeling - Eurobricks Forums

 

A rotating platform that gets elevated and has 1 more independent movement possible;

42128 C Model - Fairground Tilting multiple spinning platforms - LEGO Technic, Mindstorms, Model Team and Scale Modeling - Eurobricks Forums

 

[Jurss]

You wan't to drive both smiltuanosly, from one motor?

[zoloftking]

yes

 

[Maaboo the Witch]

3 minutes ago, Jurss said:

You wan't to drive both smiltuanosly, from one motor?

*Simultaneously

[zoloftking]

your model is brilliant but the tilting part won't work for me batmobile ramp that lift and rotate.   I tried scissor lift and that part is straightforward but linking the driver to the rotating and lifting part simultanesouly is problematic.  many solution involves a central axle but that won't work for a car platform. 

[Mr Jos]

What exactly should it do?

Go up and down constantly?

The platform needs to spin in only 1 direction, or can go down in the other direction?

How big is the piece being lifted, and how heavy?

What speed should it go up, and how many rotations per minute?

Would using 2 motors be ok?

[Davidz90]

How much space is available below the platform? If there is enough, one could use part 73763 (Worm Screw 6L) and attach it to the middle of the platform, pointing down and going through matching brick. This part has a shallower angle than regular worm gear, so pushing platform up (by whatever means, for example scissor lift you mentioned) will automatically rotate it.

[zoloftking]

platform will be the center of a long ramp and they should be 6-8L tall.   Platform (and the car on top) will elevate minimally just enough to clear from the ramp to rotate freely.  I prefer to use just one motor and the movement will be continuously preferably up and down and rotate continuously.      car size is 40433

[zoloftking]

2 hours ago, Davidz90 said:

How much space is available below the platform? If there is enough, one could use part 73763 (Worm Screw 6L) and attach it to the middle of the platform, pointing down and going through matching brick. This part has a shallower angle than regular worm gear, so pushing platform up (by whatever means, for example scissor lift you mentioned) will automatically rotate it.

David,  do you have a picture of similar set up.  I am a bit confused by it.

[Davidz90]

2 hours ago, zoloftking said:

David,  do you have a picture of similar set up.  I am a bit confused by it.

Sorry, I don't have any images. But basically, I mean that the worm gear from Lego City 60372 Police Training Academy set works both ways: normal, e.g. you rotate the worm and matching brick slides along it and reversed: you push the brick and worm rotates. Platform could attached to this worm gear and matching brick would stay on the ground. By pushing platform up/down, we cause it to rotate automatically.

[zoloftking]

On 7/13/2023 at 8:51 AM, Davidz90 said:

How much space is available below the platform? If there is enough, one could use part 73763 (Worm Screw 6L) and attach it to the middle of the platform, pointing down and going through matching brick. This part has a shallower angle than regular worm gear, so pushing platform up (by whatever means, for example scissor lift you mentioned) will automatically rotate it.

David,  for the matching brick, do you mean 73764 Brick, Modified 2 x 2 x 1 2/3 with Hole for Gear Worm Screw 6L?

[Davidz90]

54 minutes ago, zoloftking said:

David,  for the matching brick, do you mean 73764 Brick, Modified 2 x 2 x 1 2/3 with Hole for Gear Worm Screw 6L

yes