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Julc3
12-03-2008, 07:08 PM
Hello,

I want to design a computer controlled gimbal, mounted on a tripod, for a video camera. The gimbal will have 2 axis... one for pan, the other for tilt. I'm thinking to use stepper motors to actuate the gimbal.

My problem is that I have no idea where to start in regards to controlling the stepper motors. I've been reading and reading, then came across this forum. I hope this is the right place to post. I hope you guys can help me.

Here are my requirements:

- I need full control of 2 stepper motors from a laptop computer.

- Each stepper motor requires a minimum of 180 degrees of motion. 360 degrees of motion would be nice.

- The stepper motors and controller have to be powered by a 12V battery. It will be operated outdoors with no access to a power outlet.

- The connection to the computer must be either USB or serial. My laptop does not have a parallel port.

- I will be writing my own software to control the gimbal. If needed I can write the drivers also.

Is this possible on a reasonable budget? I would appreciate any leads to equipment, suppliers, useful reading material. Is there anything else I've overlooked? Basically... Where do I start? :)

Thank you very much, in advance.

Josh

cncwhiz
12-03-2008, 07:36 PM
They make remote tripods that already do what you need but the are not pc controlled? I would think that they use stepper motors to control it so you would only have to go from the motor to the pc. I dont think that usb will work. All the machines that I have seen here are using a parallel port?

TOTALLYRC
12-04-2008, 02:55 AM
Hello,

I want to design a computer controlled gimbal, mounted on a tripod, for a video camera. The gimbal will have 2 axis... one for pan, the other for tilt. I'm thinking to use stepper motors to actuate the gimbal.

My problem is that I have no idea where to start in regards to controlling the stepper motors. I've been reading and reading, then came across this forum. I hope this is the right place to post. I hope you guys can help me.

Here are my requirements:

- I need full control of 2 stepper motors from a laptop computer.

- Each stepper motor requires a minimum of 180 degrees of motion. 360 degrees of motion would be nice.

- The stepper motors and controller have to be powered by a 12V battery. It will be operated outdoors with no access to a power outlet.

- The connection to the computer must be either USB or serial. My laptop does not have a parallel port.

- I will be writing my own software to control the gimbal. If needed I can write the drivers also.

Is this possible on a reasonable budget? I would appreciate any leads to equipment, suppliers, useful reading material. Is there anything else I've overlooked? Basically... Where do I start? :)

Thank you very much, in advance.

Josh
1. What is a reasonable budget????????????????
2. Do you need it to do programable moves or do you want it to just be joggable?
3. Quick and dirty way to do it. Deskcnc and its controller card. Uses a serial interface or it can use an usb adapter. There is an sdk to write your own software.

http://www.xylotex.com/

Xylotex 3 axis kit with small steppers will run on 10-30v.
You could just write some basic G-code to do repeatable moves or use the jog buttons on the keyboard to jog the camera around.

4. You will need to read up on switching the dc input power on and off as it can cause blown circuits.

5. If you didn't need the pc you could just rig up a direction switch and then a pulse wheel to make the steps and do it manually.

6. Of course you could just buy a pc conecctable telescope tracking tripod and be done with it. Such as this. http://www.telescope.com/control/product/~category_id=goto_computerized/~pcategory=telescopes/~product_id=09743

Mike

LUCKY13
12-04-2008, 06:56 AM
Yea I think the motion really needed (programable, just jogging, set it and forget) and the budget will have a lot to say about what you needed to do.



There is also driver cards that have on board memory where you can program a pre programed set of moves and you would not need a computor to run the rig after it was setup.



There is USB & other options, the ones meantioned above, plus some others that really are not a very cheap way to go, but one is a simply way. (CNC Brain, or SmoothStepper).


Basically what is needed, is two motors, drivers for each motor, and a way to control the drivers ( PC or preprogramed with push button). This could have a wide range of needs as far as what it will take to build the system. I think a little more info on your intended use will help alot with "whats needed".

Jess

Julc3
12-04-2008, 05:53 PM
Here's a little more info... Put a GPS receiver on an RC airplane. The GPS receiver is connected to a telemetry system. The telemetry system sends latitute, longitude and altitude information to a receiver connected to the laptop (on the ground). My software will take this real-time information (5 times per second) and does the number crunching necessary to point a video camera towards the RC airplane holding the GPS receiver.

I already have a solution for the GPS, telemetry, and the real-time number crunching. Pointing the video camera back to the airplane is where I'm stuck. If I design the gimbal right, the loads on the motors will be light. The motors don't have to be super fast. I can live with an average speed stepper motor, whatever the average speed is.

As for the budget... I don't mind spending a couple hundred dollars. One thousand might be a little too much (for my wife :)).

Thanks for the links so far. I'm reading about them now.

Josh

doorknob
04-28-2011, 01:26 AM
Just curious - did anything ever come of this idea?