I just joined this forum, I have not ever used an Arduino before, I have been looking for an excuse to do a project with one, and I think I finally found one. I do have a background in electronics (2 years Electrical Engineering 30 years ago) and I work in IT. I am not a programmer, but I have done some devops, and in the past programmed in BASIC, Turbo Pascal, Fortran, shell programming (batch scripts), and a few others.
I plan to do this project together with my 11 y.o. son as well, so he can experience it too. He has Lego Mindstorms and has done some things in Scratch.
I know I have allot of tutorials to get through and I look forward to it. The purpose of this post is to get some general guidance that might hopefully help shorten the time from start of initial research to working prototype. Basically if people can point me in the general direction of a kit or modules they think will get me where I want to go, that would be great.
I have a pair of home theater DLP projectors that are used together (called “stacking”) where they both point at the same screen for more brightness. To do this requires extremely precise alignment, and these projectors have only manual controls. Right now it takes two people and allot of time to do this, one person to stand a few inches from the screen, and another to adjust the projector.
So, my idea is to use an Arduino to control a bunch of stepper motors so that this fine tuning could be done by one person easily and quickly.
Here is what I want to control:
- Focus: there is a ring with teeth on it around the lens
- Vertical lens shift: move lens (whole image) up and down, there is a ring with teeth on bottom of projector
- Zoom: a lever on top of the lens
- Yaw: shift the tail of the projector left/right with the fulcrum at the lens
- Focus and zoom would be for each projector (I could get away with just focus if necessary)
- For lens shift and yaw, only one projector needs to do this, to line up with the first projector
- To accomplish yaw, I will probably have to put the whole projector on a platform with a hinge at the front, and a worm gear or similar at the back, the projector weighs 21 lbs. I am thinking of building this out of 80/20 T-slot or something like that.
- I am fairly comfortable with what I will need to physically build the mechanicals, I think where I will need work is figuring out the size of the motors / amount of torque I will need, along with appropriate drivers.
For control, I am thinking this could be done in several ways: (not sure what would be easiest)
With an IR remote
With a physical cable, would need to be about 50’ away from the projector including cable routing
Maybe with a smart phone app of some sort or other controller
For the actual interface, here are some ways I think it could be done
Two potentiometers - one for the speed of the motor, and another for position of the motor
Series of buttons - two for motor speed +/- and two for motor position +/-
A button or buttons to select which thing to control, or have buttons for each control
Although it might be nice, I don’t think I need to keep “position memory”
Precision - I need to get down to movements of about 0.5mm or less, finer the better
I may need to do something to set maximum travel range so I can’t go past the range on the projector
Thank you in advance for any suggestions