Light Tracker Design a system that will use a servo to track

Light Tracker Design a system that will use a servo to track the brightest spot in the room. The system should report to a computer terminal or lcd the direction of the brightest spot in degrees from some calibration point (0 deg).

Solution

Using a circuit 555 you must change the control voltage and putting on resistors and capacitors for a variable duty cycle of input signal in the servo. So, using a LDR you can design to change the control voltage through of a voltage divisor depending of your preference model The equation is: Vo = VCC * R1 / (R1 + Rldr) If you assume 50 Lux like your dead point and using a datasheet for the model c-2795 we take the value for 50lux and its 70kohm. You must assume 68kohm, this is for the value of commertial resistances. So when you design with 555 circuit. The equation of periodo in high of thw signal is señores with T letter. T = -RC Ln( 1 - Vo/VCC ) The value of that periodo change the posición of servo. When the limminosity increases the resistance decrease his value and the output voltage on the voltage divisor increases moving the servo in a positive value ( more of 50 Lux ). In the opossite case the rwsistance rises and the output voltage drops. This is your ñight sensor and with the feedback of servo you can programm the output to LCD. The dead point or 0 degress is the value in case of the R1 is equal to Rldr.