HI,
I'M NEW TO THIS FORUM AND ALSO ARDUINO AND ELECTRONICS IN GENERAL.I HAVE SOME QUESTIONS ABOUT HOW TO CONTROL A PROJECT I'M WORKING ON .BASICLY IT IS AN ARM THAT IS CONNECTED TO A 12V DC GEAR MOTOR AND IT ROTATES ABOUT 170 DEGREES CLOCKWISE STOPS REVERSES DIRECTION AND RETURNS TO HOME POSITION.I ORDERED A UNO AND A ARDUINO MOTOR SHIELD.WHAT I'M WONDERING IS HOW DO I START THE MOTOR AT HOME AND THEN STOP IT AT THE 170 DEG. POSITION REVERSE IT AND THEN STOP IT AT HOME POSITION AND MAKE IT WAIT FOR A BUTTON TO BE PRESSED TO MAKE A NEW CYCLE.WHAT I'M LOOKING FOR IS WHAT TYPE OF SWITCHES AND PART NUMBERS.SO I CAN ORDER THOSE AND HAVE EVERYTHING READY TO START BUILD.
ANY HELP WOULD BE GREATLY APPRECIATED
THANKS
(deleted)
Without more experience of using an Arduino it is not practical to think of someone providing a list of parts that you can assemble into a final project like an off-the-shelf kit.
You have two options ( A ) you can start learning the Arduino system or ( B ) you can pay someone else to design (and possibly build) your project.
If you want to pay someone else to do the work you will need to ask in the Gigs and Collaborations part of the Forum.
If you want to learn the Arduino system there are many example programs that come with the Arduino IDE some of which will probably be closely relevant to your project. However you should study as many examples as you can. There are also several tutorials on the Forum and on other websites. You will also learn a lot just by reading various Threads on the Forum. With Google's help you will probably find discussions about projects that have similarities with yours.
After a bit of self-education you should have a better understanding of how to implement your project - both software and hardware.
...R
You will need to have some position feedback so that the Arduino can tell when the arm has reached the point where it should be stopped. You could use a couple of limit switches operated by the arm to achieve that.
Depending how big the arm is, you might consider using a servo instead of a geared DC motor. Conventional RC servo are available in various sizes and contain a motor, gearbox, position sensor and all the drive electronics; all the Arduino needs to do is tell the servo to go to a particular position, and the servo will go there with no external sensors needed.
Limit switches will be the simplest solution to go to pre-defined angle, but it will be much more elegant and flexible if feedback potentiometer or some other type of encoder is used. With proportional feedback one should be able to fine tune the angle....
Just from curiosity, why not stepper? much easy to spin to whatever angle you like.