Witch components do I need?

[Guus]

Hello everyone,

I want to make a system that can scan the surface of a rod. For the system I need the rod to rotate among the length axis. And I want a camera to move among the length of the rod so it can look at it from above. This way i can scan the intire surface of the rod. The positioning of the camera has to have an accuracy less than 0.5 mm. The rotation of the rod will be done by putting it on rollers and by rotating the rollers I want to rotate the rod. The accuracy of the rollers must be less than 5 degree's. So what do i want to know:

What kind of hardware do i need? (servos drivers controllers ???)

Do i need adittional software? (i already have Labview 8.2 and Vision DVM)

Are there things I'm missing?

Some extra information.

The rod has a length of 0.6<x>1.5 meter (so the side movement of the camera must be at least 1.5 meter)

It has a weight of 2<x>5 kg

It has a radius of 1.2 cm

I already have written software to detect the flaws

I also have a firewire camera

For the rotation of the rod and the slide movement of the camera i want feedback to know that they are in position and what that position is.

I've added a .doc with a little sketch of what I mean.

I know this is probably a n00b question but it is quite the investment to buy everything so I don't want to screw up.

Guus

[Guus]

Who knows what I need?

nobody?

Guus

[Buechsenschuetz]

For the rotation of the rod there is probably no off-the-shelf solution. You probably will need a set-up of rubber rollers driven by a stepper motor (with an encoder if possible) to detect rotation angle.

For the linear displacement of the camera you will need a linear stage. There are quite a few manufacturers for such items. I haven't seen them in 1.5m length personally but I am quite sure they exist. Usually a stepper motor can be coupled mechanically to such a stage without major problems (in case the linear stage manufacturer does not offer his own drives). To detect position, you can add an incremental rotation encoder to the motor. In this case you will need a reference position switch since the encoder will need several turns (and pass the index position several times) when moving the stage. You can also use a linear encoder. There are also such items like cord-driven length measurement systems. It depends on your requirements: ruggedness, cost, available space etc.

However, I think this forum is not intended to cover more than just motor drive related problems. Your problem goes much deeper into mechanical design. Probably free-lance engineers with experience in mechanical design and motor drives will provide much more detailed information.