In this tutorial we introduce the basic algorithm for following a line with one sensor and review the algorithm for quickly followwing a black line with one sensor, implementing both with the Mindstorms EV3 robotics kit.
This video lesson shows a very interesting specific example on how to use the LEGO Mindstorms EV3 Ultrasonic Sensor. The sensor detects if the catapult is loaded or if we have just fired an element. At the end of the lesson I also offer an interesting challenge that you could use in your classroom or at home.
This video lesson is a revised version of Episode #1. Matt Gipson requested it in a comment. Using the EV3-G software we have developed a very simple program for following a line with two LEGO MINDSTORMS color/light sensors.
In a competition environment like the FIRST LEGO League (FLL) or World Robotics Olympiad (WRO) the color sensor is more than useful. It makes positioning on the field quite easy and precise.
Now we have to program the robot. The steps that we will cover are starting the software, writing a program and downloading it to the robot.
Very simple and basic introduction to the color sensor in the LEGO Mindstorms EV3 set. The first program is to stop at a line. Then we can move from stoping at line to counting lines and even more complex tasks.
There is the Move Tank programming block in the software. It allows us to set different power to each motor.
In real life, the same concept is used in cars, for example. The traction control systems apply different power to different wheels, so that the car is more stable on the road during turns or on slippery road.
Robots could do chores for us and they must consider the load of the cargo or the robot could be damaged.
Would you like to resolve all the problems with the light/color sensors that you have? And to make all of them work in a predictable, stable way even when using more than one MINDSTORMS colour sensors.
When using Color sensors it is important to calibrate them depending on the light conditions in your venue. In this way, the calibrated sensor will show values between 0 and 100 independent of the light conditions. But using the default EV3 colour calibration available in the colour sensor block could lead to unpredicted problems that are difficult to track and resolved especially when used with multiple Color sensors. So in this series of tutorial we implement the calibration ourselves discussing the principles of colour sensor calibration.
The Gyro sensor in LEGO Mindstorms EV3 sets is new for the sets and we answer basic questions about its usage. The sensor detect when the whole constructions turns at a particular angle, but there are a number of gotchas in using it.
Let's implement a more advanced program for this robot to learn how to use with motors in opposite directions - and this is to implement the Proportional Line Following algorithm.
The code is already ready. It is attached below the video. Let's see how the program works and what it does and how to use it.
Sometimes when we are working with sensors it is important that the time between two consecutive samples is the same. This will make each sample equally important and independent of how much time it took to take it. In this video tutorial, we would use the EV3-G timer block to make a "WaitForTick" program where the time between each sample of the EV3 Gyro takes exactly 0.02 seconds.
Move the robot using the Move Steering block. We explore what the different values for Steering mean and how to use them. We also explore how the motor is configured to run for a number of rotations or seconds and what is the difference.
Many times we just upload blocks and leave it up to you to use it. In this tutorial, I would like to show you how to use the implemented blocks. How to import them into the EV3-G software. How to see them in the palette. How to drag and drop them to build a working program.