The GP2Y0A21 Sharp distance sensor is a great way to add obstacle avoidance or motion sensing to your robot or any other project. With a detection range of 4 to 32 (10 cm to 80 cm) and an analog voltage indicating the distance, this sensor is very easy to use.
The TMP36G is an analog temperature sensor which has a measurement range of -40 to +125 Degree C.
The LM35CZ is an analog temperature sensor which has a measurement range of -40 to +110 Degree C.
This semiconductor gas sensor detects the presence of methane (CNG) gas at concentrations from 300 ppm to 10,000 ppm, a range suitable for detecting gas leaks. The sensor s simple analog voltage interface requires only one analog input pin from your microcontroller.