- 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.
- 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
- Kit Contents: (2) Bumper Switches
- All VEX Microcontrollers
- 3-Wire Extension Cables
- Type: Momentary
- Black: Ground
- Red: No Connect
- White: Control signal
- Actual Weight (one item, no packaging): 0.042lbs (19.05 grams)