How to align to a wall with Ultrasonic Sensors. Remove complexity (part 4)
We explore some common mistakes when a program is developed and becomes complex. We then try to remove part of this complexity.
- #166
- 16 Nov 2015
We explore some common mistakes when a program is developed and becomes complex. We then try to remove part of this complexity.
This is the oldest and most classic problem in the field of robotics. Shaft in an opening. Basically robotics and in improvement of many of the actuators is about improving the solutions to such problems. Let's see how we ca do this using a mission model from the FIRST LEGO League (FLL) competition.
In the final video we explore how to trigger the release of the attachment with just a rubber band. The release is triggered with a gear wheel that rotates in a specific way. This saves speed, does not require additional LEGO Mindstorms motor and is precise enough for a competition.
If you get to a solution that is too complex you should always try to improve it. This is what we are doing here. Arriving at a solution for aligning to the wall that has become too complex.
Implementing the next logic for aligning to the border when we approach the border from the right.
We have previously aligned to lines with the Color Sensors. In this series we are doing the same program, but with Ultrasonic Sensors that are aligning the robot to a Wall.
Introducing three main concepts - Energy, Inertia Moment and Angular Velocity. We describe what is the moment of Inertia, how do we calculate it and how do we measure it?
This second part continues with importing two previously developed in Episode 53 blocks into our program. With them we can for align to lines. We program the robot to align to the cross line and start following it.
How do you detect a cross-section and move from following the main line to following the crossing line. In this series of video tutorials we are starting with a very simple solution that could work in most of the cases. It is especially useful for the FIRST LEGO League Trash Trek competition where there is such a section.
Last part of the series. The final touch of the program makes sure that it works and is following the line with the LEGO Mindstorms EV3 Color Sensor in a smooth and fast way.
Continuing with the Proportional algorithm for following lines. Smooth and stable this is the first part of the PID.
Third, and last video of this series on how to use ONE attachment to solve the FLL 2014 World Class missions.
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.
Tasks on using the LEGO EV3 Mindstorms Color sensor. Quite fun and useful for different STEM classes or just to get to know the sensor.
The color sensors supports different modes of working. In this video we are working with the Reflected light, which is not actually the detected color. Most robotics sensors actually work with reflected light and you should definitely learn how to use this mode.
The program from part 3 should be refactored and improved to make it easier to understand and support. We extract most of the repeatable behaviours in a loop and this reduces the size of the program three times in terms of the number of blocks used.
We show the principle of solving the next FIRST LEGO League (FLL) Nature's Fury 2013 competition missions. Again, without any programs, but just the principles of using one attachment for most of the missions.
Use the color sensor to count the lines and stop on the third line. We do not use the wait block for this.
How can you accumulate some energy in an LEGO Mindstorms EV3 construction an use this energy at a later moment? How does a Flywheel work, why is it important and what is the purpose? What is energy, inertial moment and angular velocity. These are just some of the questions we would answer in this series on Physics and LEGO Mindstorms.
Counting lines and stopping on the third is the subject of this video. It is important to know how to do this in order to conduct more than one experiment in STEM classes (if we consider that each line is an experiment)
One attachment to rule them all...We have seen it and it works -> solving most of the competition models with only one attachment. In this video tutorial without programming we would walk you through the principles and methods of using a single attachment for most of the FIRST LEGO League competition models. One can learn alot from using as few parts as possible to solve as many missions as possible.
In the first LEGO tutorial we started following a wall with the Ultrasonic Sensor. In this tutorial we would improve the program, remove the zig zag movement and make it very smooth.
This tutorial is about how to follow a wall with an ultrasonic sensor. The example is with a border from a FIRST LEGO League (FLL) competition, but could also easily be applied to other competitions and problems.
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.
Tasks for school STEM classes or home exersie. Try to solve them to submit your solutions below.
Previously we caught the Truck with two rubber bands. The next step was to lift it. For lifting we used the Medium LEGO Mindstorms EV3 motors. In this video we are extending the attachment so that we could catch also the Ambulance. In forth video we would explore how to release both vehicles after transporting them.