The telephone game played with LEGO Mindstorms EV3 robots relies on the Color Sensors and the detection of colors. Sometimes the robots won't work. They could be influenced by a number of factors like the position of the sensor and the lighting in the room. This tutorial is a demonstration on how to account for and resolve this issue.
As an exercise try to implement the calibration of the minimum and maximum values for a single sensor.
In this program we demonstrate how to program a SPIKE robot to follow a line with the aid of a color sensor. In this program, we use the sensor value to calculate a number to feed in the "start moving" command. The numbers in this program depend highly on the size of the wheels of the robot, the distance between the wheels, the color sensor reflected light range, the wheels friction, and the speed at which the robot moves. The numbers in the program must be adjusted for every case, and are in no meaning optimal to use as is, in other projects.
This program was intended for and tested on the Gazon robot
In this program we demonstrate how to program a SPIKE robot to follow a line with the aid of a color sensor. Make sure the line is big enough for the sensor to detect it and react to it. For some thinner lines, the speed of the robot can be lowered, but if that does not help, the program can be easily adapted to work with reflected light intensity.
This program was intended for and tested on the Gazon robot
In this program we demonstrate how to program a SPIKE robot to follow a line with the aid of a color sensor. Make sure the line is big enough for the sensor to detect it and react to it. since we are measuring reflected light rather than the color of the line, we can and have implemented multiple states line following.
This program was intended for and tested on the Gazon robot
The second level of the Robotics with LEGO curriculum for students from fifth to twelfth grades.
Students build multiple robots with thread chains and become familiar with the physical concepts of momentum and center of gravity. The concept of gears, their use and basic constructions involving gears are studied.
The new concept of "condition" is introduced in programming. Robots are becoming smarter as they can make complex decisions on their own. "Spy robots" follow their targets and avoid being noticed. This level introduces the light sensor which the robots use to recognize the colors of the objects they are looking for. Robots can stop on a black line and follow a route marked with a colored line on the floor.
The spy's most complex mission in the end of the level is to turn into a sumo wrestler and defeat any other robot in the ring.
This is the fifth level in the Robotics with LEGO curriculum for students in third or fourth grade.
For the first time robots with steering wheels are built in this level. Those robots use one or two drive motors. The work of the differential and its usage in vehicles is explored. Students learn in-depth the working of the light sensor to create better line-following programs. The first two-wheeled motorcycle-robot is built.
The kinesthetic and memory game works with a program you can download from here. In these instructions you will see the 7 modules from which it is built:
This robot is meant to be very modular and to enable its owner to upgrade it and modify it.
The CubeHunter uses the ultrasonic sensor to detect a ball or cube. Next, the robot catches it and reads the colour of the object using the EV3 colour sensor. The building instructions are suitable for classes with students and if you are working alone at home.
Umjaho - from the language of the Zulu tribe. It means "competition"
This LEGO Mindstorms EV3 robot has three sensors - touch, color and ultrasonic. When the touch sensor is pressed the robot starts moving. The color sensor is used for following lines and the ultrasonic sensor is used to detect any robots in front of the robot.
Geldautomaat, from German, means ATM.
This is the last robot from the 3.0 course book in the LEGO Mindstorms Curriculum. It uses a Touch Sensor to sense if there is a card inside. When touched, a Medium Motor starts spinning and pulls the card inside its chamber, where a Color Sensor reads the data from the card.
NOTE: There is a step, where you have to place the "credit card" inside. It may seem unnecessary and pointless, but otherwise, you will not have proper support for the next steps and the construction will crumble.
This robot was made to count coins. The door slides, making the gyro sensor rotate, and by doing that, allowing the robot to measure the size of the coin that enters the safe. By changing the points where the gyro's beam connects, the sensor's thresholds change.
Building instructions for the LEGO Mindstorms EV3 Catapult. The robot has a motor, a clutch to control it for manual shooting and a touch sensor for automatic loading. The bottom base is removed which means the Catapult could not be turned around. Nevertheless, the baseless robot is small enough to be built in class.
