Let's explain the problem of just waiting for the Gyro sensor to detect an angle and think of why the robotics systems work like that.
- #156
- 01 Jan 2017
- 3:43
Previous video tutorials:
English
Previously we tried to turn to 90 degrees the robot was turning to 97 degrees and we tried to return back the robot, but the program was not working and the question is why. Why wasn't the robot returning back a few degrees.
To answer this question we should again look at the program. What happens in the program? Why is it very logical but non intuitive. First, the robot turns forward with the motor and it turns right until we reach a value detected by the gyro sensor of greater than or equal to 90 degrees and then we stop. As we stop, we saw that the value returned by the sensor was about 97 degrees. This was displayed here in the block. Then we tried to turn back the motor, very slightly until we are at exactly 90 degrees and then stop. This was not working correctly. The real problem here is the following. While this motor turns, we wait for the sensor to detect a value exactly 90 degrees and it detects it, it stops and it runs again until we are at exactly 90 degrees. These 2 blocks here are running in a few milliseconds because the micro controller of the brick is quite fast and from this block to this block we have some milliseconds and that's why the moment that this block detects the value of 90 degrees is actually the moment that this block detects the value of 90 degrees and they are separated with a few milliseconds difference. That's why we don't get the chance to return back with the robot and the whole program ends. In order to solve this we must add one more wait block. We wait here for about a second for the whole program to stop, to wait
and then we return back with the motor. Let's run the program, first on the software. We turn, 93 and then we return to exactly 90.
Let's see this on the camera.
You'll now see the robot turn and then return.
You see this small turning back after the robot has stopped. Again, I'll run the program.
Now we are almost perfectly aligned to about 90 degrees. So it might be 89 or 91 and that's something that we'll explore in the next video.
Курсове и занятия включващи този Урок
Този Урок е използван в следните курсове и занятия.
Moving Straight with LEGO Mindstorms EV3 robots
One of the most controversial topics when it comes to LEGO Mindstorms robots is how to make them move in a straight line. This is a problem that has caused a lot of confusion among teachers, parents, rookie teams and students. The robot makes about 2-3 centimetres error for every meter, which is about an inch for every 3-4 feets. In this course, I would like to discuss the different ways in which you can improve the behaviour of the robot and how you could make it move in a straight line with the help of the LEGO Mindstorms EV3 Gyro Sensor.
- 24
- 102:09
- 3
Gyro Sensor Introduction
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.
- 5
- 0
- 3
- 3d_rotation 0
EV3 Basic Course. Introduction to robot programming, construction and sensor use
This course is designed for students, mentors and teachers that are completely new to LEGO Mindstorms EV3 robots and would like to start using them to learn, in classes or at competitions. It is quite different from previously built resources at FLLCasts because it makes no assumption on any previous knowledge and tries to introduce everything step-by-step.
- 38
- 193:26
- 30
Gyro Sensor
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.
- 5
- 0
- 3
- 3d_rotation 0
Instructors Remote Training
If you are working with students and you want to introduce Robotics to your class or you want to mentor a FLL team, but you are insecure about your technical knowledge in the Robotics field, then this is the right place for you. Having in mind teachers' busy schedule, we have design two different schedules and added an option to design one just for you. FLLCasts's Mindstorms EV3 Robotics Online Training is the perfect match for any teacher.
After the completion of each task the participant has to upload his solution for verification.
- 136
- 280:11
- 156
Gyro Sensor
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.
- 4
- 0
- 4
- 3d_rotation 0
Instructors Remote Training
If you are working with students and you want to introduce Robotics to your class or you want to mentor a FLL team, but you are insecure about your technical knowledge in the Robotics field, then this is the right place for you. Having in mind teachers' busy schedule, we have design two different schedules and added an option to design one just for you. FLLCasts's Mindstorms EV3 Robotics Online Training is the perfect match for any teacher.
After the completion of each task the participant has to upload his solution for verification.
- 136
- 280:11
- 156
Gyro Sensor Theory
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.
- 4
- 0
- 0
- 3d_rotation 0