Hi everyone,
I have a fairly complex project in mind but I want to start small and slowly add features to my system. The project is to design and build a 4-way screen masking system for a home theater. Right now one of these systems costs about $10k (not counting the screen!) so I figure I can build something for much less and publish the design for other DIYers to use. My general idea is to have a PLC or microcontroller actuate a motor so it will spin a rod (opening/closing a curtain) until a certain point is reached. The curtain/masking mechanicals are already thought out... I just need a control system for the motors. Limit switches would be employed to prevent over-excursion of the curtain. However, the curtain would need to be stopped in various positions, based on the aspect ratio of the program that's being watched. This would consist of a table in a EEPROM (aspect ratio of 16:9 go to position W,X,Y,Z; 4:3 have each curtain go to a different position). User control would be done via RF or IR remote control and would also be capable of storing settings into the EEPROM.
Inputs:
- Remote control, sends a memory lookup location -or- "bump" commands for each motor for fine adjustment
- limit switches on each curtain to prevent over extension
- Motor feedback?
Outputs:
- Control signals to control a motor or commands send to stepper motor
Questions:
- Are there 1/4HP or below stepper motors? I am having trouble finding a motor solution that is relatively inexpensive (<$100 per unit). Are there cheaper options (not necessarily a stepper motor) that will provide the functionality I need? The motor will need to 'hold' its position after a move is completed.
- I had been looking at the 'Click' PLC which seemed fairly attractive from a cost and functionality standpoint. However, I am more comfortable with PIC programming (vs 'ladder' programs) and I think a PIC + EEPROM may be more suitable (in terms of voltages being used & intended applications). Thoughts?
Once I determine my controller and motor solution I'll ask more questions about recommended sensors, etc. My plan is to breadboard a simple circuit with the controller & motor and get that working. Once that's done I'll add additional motors and the remote capability.
I have a fairly complex project in mind but I want to start small and slowly add features to my system. The project is to design and build a 4-way screen masking system for a home theater. Right now one of these systems costs about $10k (not counting the screen!) so I figure I can build something for much less and publish the design for other DIYers to use. My general idea is to have a PLC or microcontroller actuate a motor so it will spin a rod (opening/closing a curtain) until a certain point is reached. The curtain/masking mechanicals are already thought out... I just need a control system for the motors. Limit switches would be employed to prevent over-excursion of the curtain. However, the curtain would need to be stopped in various positions, based on the aspect ratio of the program that's being watched. This would consist of a table in a EEPROM (aspect ratio of 16:9 go to position W,X,Y,Z; 4:3 have each curtain go to a different position). User control would be done via RF or IR remote control and would also be capable of storing settings into the EEPROM.
Inputs:
- Remote control, sends a memory lookup location -or- "bump" commands for each motor for fine adjustment
- limit switches on each curtain to prevent over extension
- Motor feedback?
Outputs:
- Control signals to control a motor or commands send to stepper motor
Questions:
- Are there 1/4HP or below stepper motors? I am having trouble finding a motor solution that is relatively inexpensive (<$100 per unit). Are there cheaper options (not necessarily a stepper motor) that will provide the functionality I need? The motor will need to 'hold' its position after a move is completed.
- I had been looking at the 'Click' PLC which seemed fairly attractive from a cost and functionality standpoint. However, I am more comfortable with PIC programming (vs 'ladder' programs) and I think a PIC + EEPROM may be more suitable (in terms of voltages being used & intended applications). Thoughts?
Once I determine my controller and motor solution I'll ask more questions about recommended sensors, etc. My plan is to breadboard a simple circuit with the controller & motor and get that working. Once that's done I'll add additional motors and the remote capability.