Incorporating Sensors on a Competition Robot
The "Eyes and Ears" of the Robot
VEX IQ Challenges are growing as more and more students are introduced to the the wonders of robotic technology. Each year, an exciting engineering challenge is presented in the form of a game to competition participants. The object of the game is to score as many points as possible in a set period of time. One of the challenging aspects for teams is to create a robotic build to complete tasks in the most efficient way possible, earning the most points. Teams must use and rely on different sensors to achieve this goal. Robotic sensors are used to estimate a robot's condition and environment. Just like human senses, robotic sensors send electronic messages to the brain, which them enables appropriate behavior needed by the robot to solve the task.
Competition robots use many sensors in a competition:
- The Bumper Switch senses if it is currently pressed or released, and it provides that information to the Robot Brain. For example, the Bumper Switch can detect when it comes into contact with a surface such as a perimeter wall, or an object, such as a game piece.
- The Color Sensor can detect the color of an object near the sensor. This is useful if you want the robot to sort differently colored objects, drive up to a specifically colored object, or detect the color of objects as they pass by the sensor.
- The Distance Sensor uses the same principles as sonar devices to measure sound. For example, the robot can use the Distance Sensor to drive toward an object or surface until it is within a specific distance, without touching it. This can be used to make sure that the robot does not knock over game pieces.
- The Gyro Sensor on a robot allows the robot to detect how far it has turned. This is useful to enable the robot to make accurate turns on slippery or uneven surfaces.
- The Touch LED allows your robot to detect when it is touched by a finger, as well as display many different colors. For example team members can see when different sections of an autonomous program are running by programming the Touch LED to display a unique color for each section.
Motivate Discussion
Q: The Gyro Sensor can allow a robot to make more accurate turns, but how else can it be used on a robot? Can it be mounted turned on its side?
A: The Gyro Sensor can be mounted turned on its side to measure the angle that the robot tilts up or down. For example, the Gyro Sensor can measure the angle of a slope that the robot is traveling up. The Gyro Sensor can also be used to accurately raise or lower an arm on a robot a certain number of degrees.
Q: How can the Distance Sensor be used on a robot in a competition setting?
A: Answers may vary, but one possible way is to determine how far away the robot is from walls or other robots. This ensures that the robot will not collide with other robots or a surface that could potentially damage it.
Extend Your Learning
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This Year's Game
As an extension activity, ask the students to view this link to learn more information about this year's VEX IQ Challenge game.
Have students brainstorm and write their ideas in their engineering notebooks about how they could use sensors to program their robot to score points. Encourage students to provide sketches of a potential robot build. Facilitate a discussion with the students by asking:
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Which sensor would you use and why?
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Where do you think is the best location for this sensor? Does the location matter at all?
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Can you use more than one sensor? How could this be a benefit?