Vladi Gergov

The control for the three lighting systems LED ( Light Emitting Diodes ), Incandescent, and Fluorescent is achieved with a small embedded computer based on the PC/104 standard. This embedded computer is around three-hundred MHz and comes with an on board digital input/output expansion card designed around the Motorola HC12 micro-controller. Motorola's HC12 micro-controller provides the embedded computer with control over a multitude of digital/analog inputs and outputs. The input/output card is manipulated via a C program running on the GNU/Linux operating system. The C program configures the HC12 with PWM ( pulse width modulation ), frequency, channel, and off-time. Off-time is determined by the user and is entered from a form on the embedded computer's website corresponding to each lighting system. The website in turn calls the C program via PHP ( PHP Hypertext Preprocessor ) script with the given light system variable, channel variable, frequency constant, and off-time variable. The corresponding lighting system then receives the synthesized PWM signal from the HC12 and a corresponding light brightness is produced. Next the PHP script saves the previous screen shot of the lighting conditions and the previous values for the lighting system modified and PWM values modified. After which a new screen shot is taken of the current lighting conditions. The new home page is then dynamically generated to display “before” and “after” lighting conditions and “before” and “after” light system/off-times used. Then the website is ready to get new off-time values for the whole process to begin anew. This “remote control” process is the underlying idea underneath our whole design project. To think that an engineer has the ability to be anywhere there is Internet access and have absolute control over the machine vision system be it for fine tunning the lighting system or just monitoring the current conditions is revolutionary. Therefore this is a very useful application that can save a lot of cost by removing the need for an engineer/technician that needs to come on site if there is a problem and regulate the system periodically. The initial cost of the system will be high but given time the system will pay for itself and begin to save costs.

2004-04-06T23:08:48