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Any idea for this TurnTable?

Any idea for this TurnTable?

Postby argo » Thu Nov 28, 2013 8:08 pm

Hello,

Just finished my turntable but there is a problem and i mean serious problem.
as you see i connected the gear wheel directly to the step motor. which makes the stroke on the gear wheel and that causes, movement of the object on each few steps.
I know that i have to use a belt to connect the motor and gear wheel to get ride of this problem. but here i can not find any belt. :oops:
any idea?

I really have no idea that i could explain the problem or not. :roll:
Regards,
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Re: Any idea for this TurnTable?

Postby hunkatibor2 » Thu Nov 28, 2013 8:19 pm

Hi argo
I do not understand the problem. Works? Rotates the table? Since the controller?
Tibor
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Re: Any idea for this TurnTable?

Postby MagWeb » Thu Nov 28, 2013 10:22 pm

If I got argo right, this seems to be a problem of the steppers acceleration which is 0 to Max with the first step and Max to 0 with the last. Due to the inertia of the object this may move.

Besides using some reducing transmission as a belt or a gear there are a few things you could try:
- use another stepper which makes more steps per round;
- Optimize the transmission of force between turntable and object. Here I use plasticine or wax as it is used to fix candles to "glue" the object onto the table.
- Or to modify the controllers code to perform "ramps" at start and end of a motion. These ramps make the the table speed up and slow down in a smoother way.
Don´t know which hardware and software you use to controll the stepper...
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Re: Any idea for this TurnTable?

Postby hunkatibor2 » Fri Nov 29, 2013 7:06 am

Hi argo
I have a mouse problem. I use this double-sided foam adhesive. Very firmly anchored in the subject, even vice versa. Mach3 has a ramp that I use.
Tibor
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2 Basler A622F camera 2 Tamron Asfirical AF 28-80mm lense
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Humanti Calibration panel system and Alignmed&Two camera
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Re: Any idea for this TurnTable?

Postby argo » Fri Nov 29, 2013 9:12 am

MagWeb wrote:If I got argo right, this seems to be a problem of the steppers acceleration which is 0 to Max with the first step and Max to 0 with the last. Due to the inertia of the object this may move.

Besides using some reducing transmission as a belt or a gear there are a few things you could try:
- use another stepper which makes more steps per round;
- Optimize the transmission of force between turntable and object. Here I use plasticine or wax as it is used to fix candles to "glue" the object onto the table.
- Or to modify the controllers code to perform "ramps" at start and end of a motion. These ramps make the the table speed up and slow down in a smoother way.
Don´t know which hardware and software you use to controll the stepper...


Hello Gunter,
You got my problem just perfectly.
I use an Arduino uno, a driver and 1.8 stepper motor.
I dont know if you mean speed!! by acceleration or not. no matter what stepper speed i set, there is always a stroke. anyway i could not find any code regarding acceleration of motor.
Regarding the library, the codes for Arduino are very limited.

I think your second suggestion " using was or plasticine" is just perfect.
Thank you so much for the help

hunkatibor2 wrote:Hi argo
I have a mouse problem. I use this double-sided foam adhesive. Very firmly anchored in the subject, even vice versa. Mach3 has a ramp that I use.
Tibor


Hello Tibor,
did you mean "mouse problem = mouse pad" ?
I think i got your point. and those mouse pads also are good but some of objects are so lightweight and anyway they will jump and move. I guess that wax Gunter mentioned is just enough and easy
Thank you

Best Regards,
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Re: Any idea for this TurnTable?

Postby MagWeb » Fri Nov 29, 2013 10:34 am

Argo,

here's another product to fix the object: http://www.amazon.com/Saunders-Removabl ... ds=patafix
(there are also similar product of different brands)
This is the kind of wax I mentioned : http://www.amazon.com/Candle-Adhesive-B ... hesive+wax

@ Speed: the speed of a single stepper's step is constant, but you can modify the speed of the overall performance using variable delays between the single pulses. If you use an easydriver board here is a code snippet that should do what I mean (not tried here). Maybe in your case (only a few steps per round) you should consider microstepping mode:
http://forum.arduino.cc/index.php?topic=22677.0
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Re: Any idea for this TurnTable?

Postby argo » Fri Nov 29, 2013 11:18 am

Gunter,

This is a really good idea to set a delay between each turning on(High) and turning off(Low) the pins.
Thanks for the link. i will modify my codes and will inform you about the results.

Best Regards,
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Re: Any idea for this TurnTable?

Postby argo » Sat Nov 30, 2013 9:15 pm

Hi,

The delay, could not make the motor movement any smoother. it is just useful in some cases that you speed up the motor and need to control the acceleration! (I am not familiar with mechanical or electronic things but i guess in high speed it may occur to lose steps so they set a delay!!?)

here is a place that Walter's knowledge is needed (i missed him and hope he is doing fine and comes back soon)

anyway i solved my issue by using double-sided adhesive :wink:

Regards,
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Re: Any idea for this TurnTable?

Postby oddamann » Mon Dec 16, 2013 9:54 am

Hi

http://learn.adafruit.com/adafruit-moto ... pper-class

I think I know what problems you have - got the same on StepperBee

The Stepper go 1.8 degree each step and that's what couse the vibration.
With Microstepping this will be smoothed.

can you post your code / project - and I will order Arduino Uno - and the shield for stepper
Since I just have done the project with Stepperbee - ( with no option for microstepping)
I would like to get in to Arduino programming...
viewtopic.php?f=9&t=5928
best regard's
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