DIY and Entry-Level 3D-Scanner Forum

Hi All,

I own 4 PrimeSense 1.09 scanners (using 2.5 lens) which I plan to place evenly on a 2m high tripod stand. I have attached below an example image of the goal setup. My goal is to automate the scanning of a person by getting them to stand on a motorized turntable. My question is, what is a recommended speed (RPM) that I should use for the turntable in order to get the scan possible.

Kind regards,
Berkal

That's probably something you're going to have to experiment with a bit to determine. It probably will vary depending on how large the objects are you're scanning. I'd suggest powering your turntable with a motor whose speed you can control pretty finely, like a DC motor with a rheostat or a stepper motor with a motion controller.

Andrew Werby
www.computersculpture.com

Hi,

Could you recommend a motor than is able to handle a load of say 150kg. The torque needs to high enough to not slow down regardless of weight of the person standing on it (say up to 150kg). Where could I purchase this motor as well as the rheostat?

Kind regards,
Berkal

I wonder, if a person can stand without moving on such a turntable. This method works well for solid objects, but I don't think it is the best option for scanning people.

What about moving the sensors around the person? The person stands in the center and the sensors rotate around the person.

What do you think? Could this approach work?

_________________
Bernhard
www.virtumake.com

I thought about moving the sensors instead but then I found someone using a turntable to scan and the quality looks good. He's using a Kinect scanner so just imagine what the quality will be like with a Pimesense 1.09 with 2.5 lens.
http://thegreatfredini.com/scan-a-rama/

Kind regards,
Berkal

Berkal wrote:

Could you recommend a motor than is able to handle a load of say 150kg. The torque needs to high enough to not slow down regardless of weight of the person standing on it (say up to 150kg). Where could I purchase this motor as well as the rheostat?

[The person doesn't have to be perched on the motor; the motor just moves the turntable. What you need to do is to build a large "lazy Susan" turntable, preferably with thrust bearings, that will support the weight of a person and allow them to be spun around with a minimum of resistance. Then mount a motor so that it powers a rubber wheel that contacts the underside of the turntable at the edge, so that as it spins it imparts motion. This won't take a huge motor; its size would depend on how much resistance your turntable has to spinning when loaded, how big the rubber wheel is, and how fast you try to spin it. Since you don't need much speed, a relatively small motor (1/4 hp?), geared down, would probably work fine.]

Andrew Werby
www.computersculpture.com

Thank you so much for your response Andrew. If you could provide a link to this motor would be greatly appreciated.

Kind regards,
Berkal

I don't think the motor has to be anything special, but here's a link to a variable-speed DC gearmotor: http://www.wondermotor.com/Rotisserie_motor.html They show it spinning a whole hog and a motorcycle, so it should be powerful enough to spin a well-balanced turntable with a person on it. Another alternative would be to spin the turntable by hand; perhaps with a simple crank mechanism. If you can't find thrust bearings big enough (or they're too expensive) you can probably build something with a regular axial bearing in the middle, and support the weight towards the edge with ball-bearing casters, assuming you've got a flat level surface for them to roll on.

Andrew Werby
http://www.computersculpture.com