The topic of the thesis is the redesign of the Digital Holographic Microscope’s control unit which is under development at MTA SZTAKI. During the redesign I made a control unit capable of controlling lasers in impulse mode, driving DC and stepper motors and switching valves. I made a program for controlling the unit from a computer and this can be easily implemented into the DHM software.
In the beginning of the development I examined the old control unit, and tried to find out what modules should be changed. I analysed the lasers if they can be driven in pulse mode and the camera of the DHM can be synchronized with them.
In the next step I have chosen a microcontroller and I get acquainted with its development environment. I have broken the task into small pieces and slowly made the code that can control the lasers and the camera.
For controlling the stepper motors coil currents I have chosen a dedicated integrated circuit, and implemented the signal controlling in the previously chosen microcontroller.
I also integrated the DC motors signals in the microcontroller and I kept the power electronics from the old control unit.
Finally I started planning the printed circuit. First I got to know the printed circuit designing software called EAGLE, and then I planned the schematic. In the planning process I was correcting the upcoming problems. This is how a new circuit was made for producing the 24 V. After the schematic was finished I planned the printed circuit board, generated the GERBER files and I send them to the PCB manufacturer.
The new control unit is communicating through USB with the PC and capable of controlling three pulse mode lasers and a camera all of them synchronised, driving two stepper and two DC motors, switching eight valves and reading four digital sensors data.