This is the first video tutorial from our course on LEGO MINDSTORMS Robot Inventor programming. In this tutorial we will start with how do we move without sensors. We will demonstrate a simple program. Our hope with this tutorial is that you will see why moving without sensors is a bad approach.
- 03 Oct 2022
- LEGO MINDSTORMS Robot Inventor
- FIRST LEGO League, World Robot Olympiad, Robot Base Chassis, Scratch, LEGO MINDSTORMS App Word Blocks
Moving without sensors is bad
The problem here is the fact that moving without sensors is not reliable. The robot will make mistakes. There will be bumps and slips and different behaviors of the robot and many many other things. This means that it is very unreliable to move without sensors. The tutorial will demonstrate this. See how difficult it is to reach the same place every time.
As the first tutorial from this course, we will start with how do we move with a LEGO Mindstorms Robot, Inventor robot on the field without the use of any sensors. This is our small robot base. It has two motors, driving motors and two for attachments. Our goal is to demonstrate how do we move. Here it is. We start from the base. Move forward, rotate, move forward. And as you saw, we arrived at a specific place on the field. And can we repeat this? How reliable and consistent is the robot without the use of any sensors? Just move forward, turn, move forward. What you can see is that it kind of gets to the same place, but not exactly. And my point here is what I hope we can demonstrate from this tutorial is that moving without the use of the sensors, it's possible, and you can do it for missions that are near the base, but generally it's not very reliable. Let's see the program now for this robot. This here is the program for LEGO Mindstorms Robot Inventor. And it's scratch again. It's pretty similar to LEGO Education. SPIKE prime. Prime Word blocks. It's a different app. You have to download it in a different way and you have different extensions from the programs. I don't know why this is, to be completely fair here, not completely sure why we are doing it, but we have a different application for robot inventor than the one that we have for Education Spike Prime, although the two robots are basically the same. So on the right we have the robot recording, and on the left we have the program. When the program starts, we want to set movement motors to A and B. So the two driving motors are A and B. And we move forward for 30 CM. We turn left, we move forward for 50. We stop and we exit the program. This is the program and this is the recording. Move forward,
then turn left, then move forward again.
This interesting thing here is the set movement motors to A and B. And this is the block with which we set, which are the driving motors, which are the motors that should be controlled when we call the move block. So, as you see in the move block, we don't specify the motors. We must specify the motors. Before that, we say these are the movement motors. And from then on, every time we execute the move lock, we will direct the power to motors A and B. We will control the motors A and B. That's it. That's for our first program with the LEGO Mindstorms Robot Inventor. And we'll continue exploring the consistency and reliability of this robot. And with this tutorial, I hope what you can see is that it's not very consistent and reliable to just try to use the movement of the motor to position the robot on the field. But it's a viable thing for something that's near the base. See you in the next tutorial.
Courses and lessons with this Tutorial
This Tutorial is used in the following courses and lessons