In this chapter, we will look at three sensors that we can use to add obstacle avoidance and/or collision detection to our projects. These sensors are:
- Crash sensor: Used to detect a crash and also used as limit switches for 3D printers
- Infrared obstacle avoidance sensor: Used for obstacle avoidance for robotics
- Ultrasonic range finder: Used for obstacle avoidance for robotics and has many other commercial and military uses
