Bumper Switch (2-pack)

• Bumper Switch Sensor: The bumper sensor is a physical switch. It tells the robot whether the bumper on the front of the sensor is being pushed in or not.

• Benefits:The bumper switch can help the robot avoid dangerous collision automatically.

• Switch Info: SPST switch (“Single Pole, Single Throw”) configured for Normally Open behavior.

• Switch Connection: Wired to normally open (OFF)

• Signal Behavior: When the switch is not being pushed in, the sensor maintains a digital HIGH signal on its sensor port. This High signal is coming from the Microcontroller. When an external force (like a collision or being pressed up against a wall) pushes the switch in, it changes its signal to a digital LOW until the switch is released. An unpressed switch is indistinguishable from an open port.

• Range Limits: Forces less than a pound can trigger the bumper switch (5.06 oz typical).

The bumper switch can allow a robot to navigate autonomously by avoiding hard collisions, such as hitting a wall. For example, a robot can be programmed to briefly freeze when the bumper switch is activated, and then reorient itself so that it is no longer driving towards the obstacle. Figure 2 shows where the bumper switch would be placed to be the first part of the robot to make contact with a wall or an obstacle.

Figure 2. (a) Bumper switch placement; (b) Placement close-up

• ROBOTC Sample Code
• easyC Sample Code