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Electronics => Electronics => Topic started by: Hybridvisions on December 16, 2011, 11:07:58 AM

Title: Help needed -system- Axon2 to use as encoders to Motors on a Pan/tilt/roll
Post by: Hybridvisions on December 16, 2011, 11:07:58 AM
Hi folks
I'm  purchasing this rig from servo city and I'm looking to add an encoding & software system so I can record and replay the actions on the Pan/Tilt/Roll  motors.
http://servocity.com/html/pt-2100_pan__tilt_system.html (http://servocity.com/html/pt-2100_pan__tilt_system.html) with the additional roll system .

I'm looking to add additional motors/ servos to act as follow focus & zoom.

The rig will be mounted on a 8-12 ft jib so needs to have a good controller wireless possibly might be a good option but not crucial

My research suggests that the Axon2  would be really suitable for this as an encoder, but its a new area for me.

My parts assumption is :

Servo motor
Speed control motor
AXON II
Controller ... ps2 controller
software to record actions
Batteries

Is this correct?

Could you recommend the motor & parts choices for this system?

We are due to start principal photography on the film we want to use this for late Jan.

Can you have a film credit as tech advisor ... of course... lol


Look forward to hearing from you
S
Title: Re: Help needed -system- Axon2 to use as encoders to Motors on a Pan/tilt/roll
Post by: Soeren on December 16, 2011, 02:54:29 PM
Hi,

The rig will be mounted on a 8-12 ft jib so needs to have a good controller wireless possibly might be a good option but not crucial
Using cable will be both cheaper, less troublesome and give a more stable signal transfer.


My research suggests that the Axon2  would be really suitable for this as an encoder, but its a new area for me.
You cannot use a microcontroller board as an encoder, but you can use it to record the encoder data of course.


My parts assumption is :

Servo motor
Speed control motor
AXON II
Controller ... ps2 controller
software to record actions
Batteries

Is this correct?
Hard to say, as it's not totally clear to me what you're trying to make. Is it a controller or just a "recorder"?
And what is your background (in relation to electronics, mechanics and programming)?


Could you recommend the motor & parts choices for this system?
Are you starting completely from scratch?
What cam will be used (weight/size)?
How stable is the jib?


We are due to start principal photography on the film we want to use this for late Jan.
Then you're in a hurry... No X-mas peace for you  ;D


Can you have a film credit as tech advisor ... of course... lol
You mean on the "Toronto Film Makers Club film"?
All that I ever dreamt of ;)
Title: Re: Help needed -system- Axon2 to use as encoders to Motors on a Pan/tilt/roll
Post by: Hybridvisions on December 16, 2011, 03:21:28 PM
See those dreams do come true, it is christmas after all   :)



Title: Re: Help needed -system- Axon2 to use as encoders to Motors on a Pan/tilt/roll
Post by: Hybridvisions on December 16, 2011, 03:39:05 PM
lets assume I'm a complete, beginner from the electronics side of things.
Mechanics and software I'm OK.
Jib & weights & loads are all sorted.

Its the electronic side I'm not familiar with.


A simple flow diagram etc then id be fine , and having spoked to a few Motion control companies they are all offering various options .
However I have received  conflicting responses so just asking for clarity as to the flow and of course any recommended software, preferably open source.

S
Title: Re: Help needed -system- Axon2 to use as encoders to Motors on a Pan/tilt/roll
Post by: Soeren on December 16, 2011, 04:05:41 PM
Hi,

Its the electronic side I'm not familiar with.
OK, but you have to spill whether you need control or just "recording".


A simple flow diagram etc then id be fine , and having spoked to a few Motion control companies they are all offering various options .
However I have received  conflicting responses so just asking for clarity as to the flow and of course any recommended software, preferably open source.
Now I'm puzzled. Your only weakness is in the electronics and you think you'll be be OK with just a flow chart?

If you want to use a microcontroller board, you have to do the programming yourself. You will probably be able to find something slightly similar that you can modify, but you won't find something that covers your exact purpose.

You know what your plan is and what you need help with. We don't and we really suck at guessing so...
Title: Re: Help needed -system- Axon2 to use as encoders to Motors on a Pan/tilt/roll
Post by: Hybridvisions on December 16, 2011, 04:29:57 PM
oops... I'll try to be clearer

often as a visual learner the best way to start is a flow chart, list or similar so I can understand the order and connections I need to further learn about.

I'll need both control and the recording .

Having seen the Axon used on various servos , motors setups ,it seemed the ideal controller to use with lets say a ps2 controller and a laptop.
Title: Re: Help needed -system- Axon2 to use as encoders to Motors on a Pan/tilt/roll
Post by: Soeren on December 16, 2011, 05:24:31 PM
Hi,

I'll need both control and the recording .

Having seen the Axon used on various servos , motors setups ,it seemed the ideal controller to use with lets say a ps2 controller and a laptop.
Another user recently told me about this software (http://www.brookshiresoftware.com/vsa_overview.htm) and I think it may be just what you need.
Title: Re: Help needed -system- Axon2 to use as encoders to Motors on a Pan/tilt/roll
Post by: Admin on December 17, 2011, 01:11:24 AM
I assume what you want is a play-back recorder. You program it to go through some motions, and it'll repeat it for you smoothly.

You will only need to buy a quadrature encoder for each motor, and a microcontroller (with many interrupt I/O, such as the Axon II). WebbotLib has libraries to make using quad encoders easy.

The system you linked has motor drivers and everything else that you need.


You have two options:
You will have to hack into the controller. It uses those two joysticks to control the two built-in motor drivers. So, you need to remove the joysticks and attach your microcontroller into that location instead, wiring your own stuff into the circuitry. This will require a bit of fiddling. For me, it'll probably take ~30 minutes of effort to reverse engineer it. But if you're an electronics beginner, it might be a huge challenge . . .

So the second option is to just throw away the controller. Buy your own motor driver(s), and just follow the easy wiring instructions in WebbotLib.


We can help you from there with whatever you decide.
Title: Re: Help needed -system- Axon2 to use as encoders to Motors on a Pan/tilt/roll
Post by: Hybridvisions on December 17, 2011, 08:42:02 AM
The system will need to include controller , joystick or PS2 pad with the ability to capture the data , for playback.
On some occasions the playback may not be needed depending on the use

Are there any particular quadrature encoders you would recommend ?

Thanks

Title: Re: Help needed -system- Axon2 to use as encoders to Motors on a Pan/tilt/roll
Post by: Admin on December 18, 2011, 08:14:47 AM
Are there any particular quadrature encoders you would recommend ?
What resolution do you need? ;)

Just go onto mouser.com and digikey.com and browse around. There are quite a lot out there.