Hi Benjamin, this is my opinion..
Benjamin WROTE:Hi, can i one of the temperature sensor with LDR.
You mean, you want to replace one of the temperature, LM35 (3 pins) with LDR (2 pins)? Yes you can, but you need to modify your circuit and need to add a pull up resistor (about 10kohm).
Benjamin WROTE:can i replace one of the brush fan with servo motor?
Yes, but you need to modify your circuit again. If you refer to PR11 schematic, there only have 2 pins for fan A, now you need to change it to be 3 pins for servo (VCC, GND and servo pulse).
Benjamin WROTE:did I need any servo motor driver for it and which servo motor driver is suitable for it.
There have many ways to control servo, to be easier you can get the
servo controller. However you also can program it directly from PIC, but you need to use interrupt timer program to produce 50Hz at servo pulse.
Request for complete solution for FYP? Why don't request for graduation certificate?