retrolefty:
Arduino is powered through a 9V battery and the motor driver with 12V battery... Bluetooth, LCD , distance sensor are powered from arduino's 5V,
Your main problem is that a small 9 volt battery will never be able to supply enough current for those devices, not enough current capacity. Even with a proper battery with enough current you will still be limited by the arduino 5V current capacity to power that much external stuff. You will need to use an external +5vdc power source with enough current capacity for all that stuff. How much current? Can't say without looking at the datasheets for each of the external devices to see what they require.
Thanks for replying.. Let me tell you again, only distance sensor , Bluetooth and LCD are powered through arduino, nothing else..It's certainly not "too much staff".. Arduino's current consumption,with everything on and working, is a total maximum of 100mA(measured with a multimeter). So my problem is not the battery, it's if i do need capacitors to protect my system..