How It Works
Lola Rabbot functions in the Space Jam field by utilizing a few different sensors.
First, there is a beacon detector at approximately 12”, which uses a phototransistor to pick up IR light. Our software processes the incoming signal using an input edge capture to determine the period, from which we can decipher which beacon we are looking at (Red Goal, Blue Goal, Red Reload, Blue Reload).
Second, there are 4 tape sensors mounted in a kite pattern: one at the front, two on either side (separated by more than the width of a piece of electrical tape), and one in the center of the robot. After finding the correct beacon, Lola drives straight to head towards the reload tape line and continues until the center tape sensor sees black. Then, the robot rotates clockwise until the front sensor sees tape. At which point, the robot follows the tape (utilizing the two side sensors).
Third, a limit switch is mounted behind a bumper on the front of the robot. When the switch is hit, we know that Lola has hit something (either a robot or a wall). During reload, this limit switch event cues the reloading process.
The fourth set of sensors involves an IR emitter and receiver pair mounted at 8” and 6” respectively to “handshake” with the reload station. The receiver works similarly to the beacon detector by reading in the signal that is being sent out at a particular height. We then transmit out the correct signal on the emitter (2 times the frequency seen at detection). At which point, a ball is released. In order to know that we have received the ball, there is an beam break circuit located at the back of the ball ramp right before the servo horn to stops the ball from falling downward.
Offense and defense work utilizing the same set of sensors, with the addition of a flywheel that is turned on and off in order to shoot balls into the goal. Before shooting, Lola will turn to face the correct goal using the beacon detector. Once the flywheel is appropriately warmed up, the servo will turn allowing the ball to fall down to the shooting ramp. At the end of offense, the servo will return to its resting position.
To indicate which team Lola is playing for, there is a simple switch that updates the team for the software and also lights up the corresponding color LED. Additionally, there is a white LED that lights up during the game and turns off when the game is over.
See a video of Lola Rabbot in action below!
First, there is a beacon detector at approximately 12”, which uses a phototransistor to pick up IR light. Our software processes the incoming signal using an input edge capture to determine the period, from which we can decipher which beacon we are looking at (Red Goal, Blue Goal, Red Reload, Blue Reload).
Second, there are 4 tape sensors mounted in a kite pattern: one at the front, two on either side (separated by more than the width of a piece of electrical tape), and one in the center of the robot. After finding the correct beacon, Lola drives straight to head towards the reload tape line and continues until the center tape sensor sees black. Then, the robot rotates clockwise until the front sensor sees tape. At which point, the robot follows the tape (utilizing the two side sensors).
Third, a limit switch is mounted behind a bumper on the front of the robot. When the switch is hit, we know that Lola has hit something (either a robot or a wall). During reload, this limit switch event cues the reloading process.
The fourth set of sensors involves an IR emitter and receiver pair mounted at 8” and 6” respectively to “handshake” with the reload station. The receiver works similarly to the beacon detector by reading in the signal that is being sent out at a particular height. We then transmit out the correct signal on the emitter (2 times the frequency seen at detection). At which point, a ball is released. In order to know that we have received the ball, there is an beam break circuit located at the back of the ball ramp right before the servo horn to stops the ball from falling downward.
Offense and defense work utilizing the same set of sensors, with the addition of a flywheel that is turned on and off in order to shoot balls into the goal. Before shooting, Lola will turn to face the correct goal using the beacon detector. Once the flywheel is appropriately warmed up, the servo will turn allowing the ball to fall down to the shooting ramp. At the end of offense, the servo will return to its resting position.
To indicate which team Lola is playing for, there is a simple switch that updates the team for the software and also lights up the corresponding color LED. Additionally, there is a white LED that lights up during the game and turns off when the game is over.
See a video of Lola Rabbot in action below!
