In the prototyping process, it may be useful to use some simple sensors to allow the prototype to communicate with its surroundings. Typically, these sensors relay the information they connect with some kind of microcontroller, which allows the user to add some causal meaning to the data from the sensors. This article will outline a few common sensors used in prototyping and how they can be used in a project.
A touch sensor is designed to allow a prototype to feel its surroundings. Typically, there have some kind on button that can be pressed that indicates the sensor has met an obstacle. Touch sensors are good for projects where it is necessary to navigate an environment, but are somewhat trivial comparitive to similar sensors that don't require direct contact, like an ultrasonic sensor.