Continuous rotation servos interfaced with this "memory

Dear Servo experts: I found this interesting kit and
am wondering the following:

**broken link removed**

Will it work with continuous rotation servos???

My idea: Use it for timelapse control.

Turn knob full revolution and pause and then then stop recording.
Play-back in continuous play mode.

In your humble opinions:
Will it cause in play-back mode one rotation of the servo
and stop and then on the second cycle repeat??? No jumping
to different first position???

In short, will this work for continuously rotating servos???

Best regards.

TIMELAPSE

Servo don't have continuous rotation, the potentiometer used for their positional feedback can't rotate more than 270 degrees - and are usually limited to considerably less than that.

You can modify servos to give contiuous rotation (they are commonly used in this way for powering small robots), but it's no longer a servo, just a DC motor and drive train.

Thanks Nigel More....

Dear Nigel: Thanks...I guess my idea won't.
Might as well use a DC motor and an on and off switch!!! :lol:


Another idea....I see lots of stepper motor controllers
made from PICS.....and they usually only give serial port
control. I want a standalone application using a PIC.

Rotate one rev and stop for 5 seconds....but this is burned into a PIC...no connection to computer serial port.

Any ways to do this would be great...links...readymade things not
costing a lot of dollars (some controllers are for 6 steppers and
cost 400 dollars etc.)

Just need a simple control (standalone) for one stepper connected
to a movie camera drive shaft (1:1).

Thanks again,
Steven

Re: Thanks Nigel More....

TIMELAPSE said:

Rotate one rev and stop for 5 seconds....but this is burned into a PIC...no connection to computer serial port.

Click to expand...

It would be very easy to do with a PIC, you just need a few driver transistors and a suitable program (which would be easy to do).

To Nigel...can you write code???

Dear Nigel: I have never written code for a PIC.

I have this idea: Modify this kit.

https://www.electro-tech-online.com/custompdfs/2005/11/ck1402.pdf

That is....get a PIC to generate or emulate 2 pulse trains 90
degrees apart to mimic the encoder in this kit (don't use the
encoder) but feed the pulses from a PIC into the encoder inputs of
the kit. Then have the PIC also stop the pulses so that
the stepper motor will stop too for a period and continue.

Can you write the code for me??? I would like delays (after
one revolution) of 1 up to 30 seconds. If that is too much,
5 input switches to give 1 second delay up to 5 second delay
after one rotation and over and over until I want to stop.

Best regards,
TIMELAPSE.

To Nigel...must run counterclockwise.

Dear Nigel: Hi! One more thing if you are prepared to help!

The step motor must run counterclockwise due to the workings
of my camera.

Best regards,
TIMELAPSE.

Hiya Timelapse,
First of all what type of stepper motor do you have ? The easiest way to check is count the wires coming out, 4 wires means either a reluctance or bipolar stepper, 5 wires or more is a unipolar but 5 and 6 wire motors can also run bipolar. For a bipolar motor you need a H-bridge to drive it whereas a unipolar motor is much simpler to drive. Once you have the motor sorted out I can post up some simple stepper code. Anyway try and get a book called 'easy steppin' br David Benson. That book is an execllent intro into controlling stepper motors via a pic.

Hope this helps

Cheers Bryan

Bryan1 to the rescue???

Dear Bryan 1...thanks for the response as well.

My motor is a Vexta stepper 2 phase 12V 0.42 amp and 6 wire.

I have seen the book you have mentioned but time is off the
essence!

So....if you can write the code that would be great!

I have a PIC....it is a PIC16F84A...does the F mean flash???

I have made a kit before (stepper with serial control) but EMF or something blew up my serial port on my computer! :cry:

So, I hope to find someone here who can write some standalone
code for a PIC that can either drive the stepper directly through
a darlington array or something and have some routines to stop the stepper after 1 rev counterclockwise and wait from 1 to 30 seconds and continue to do the same *or* have a PIC make encoder
signals (90 degrees apart) to feed into the KIT above (see a few posts back about Encoder stepper) and have delays as well.

So PIC wizards...help! :wink:

Best regards,
TIMELAPSE.

Well in the book I mentioned is all the code and how to hook it up. If time is of the essance as you say then get a hold of that book and READ IT!!!
The book has everything you need and as far as the code goes I was only going to send a snippet straight out the book to assist you. Don't expect anybody to be your code guru as everybody has there own hobbies and we're not here to do your work for you. GET IT.
This forum is here to assist people with electronic issues and we're not here to be on beck and call to everybody that can't be bothered to think for themselves.

Bryan 1

Dear Bryan 1 : Whew....I didn't expect such a harsh response!
I am not lazy! I am not!

I thought I was genuflecting and asking nicely.

Anyway, thanks for the reference. I'll have to read the book then! :wink:


Best regards,
TIMELAPSE.

OK Timelapse,
That last post of mine was in my view justified due to your demands in your previous posts. So if your willing to help yourself I'm willing to assist you in getting started.
Firstly have you identified the wires correctly to hookup to a driver board? If so below is a simple program that will rotate a unipolar stepper every 200 milliseconds approx clockwise. The code is from the book and is designed for the 16f84a pic chip ( the 'F' stands for flash)

Once you have that working think out what you need to do next and amend the hardware and code. Do it one step at a time so if it goes wrong you won't spend hours debugging the code. I did the same thing with my cnc project only using a bipolar motor and a different pic and expanded the code to stop when a switch is detected etc. It isn't hard but you do need to know the basic's of pic's and I would suggest to look at the first post in the microcontrollers forum and get some reading done of the huge resource of links there.

Let us know how your getting on once you have the stepper working and have added a few things and we can help you out. So hopefully this will get you started.

Cheers Bryan

Bryan 1 Thanks!

Dear Bryan 1....Thanks much! Thanks.

That's a very good start. I think I have an idea....with the
input to stop...I can use a 555 timer circuit to output a pulse to vary the
stop range.

The wires??? Yes indeed....I have figured out the motor wires...
2 wires are center taps and the rest of the 4 are for driving.

Thanks again.

Best regards,
TIMELAPSE.