Repeat the program for reaching the end of the rock and waiting for several seconds, although it might need some adjustments. After that the robot should make a 90-degree turn by first turning its tail fin, then going several rotations forward and then straightening its tail fin. Next, the robot continues forward until it reaches the wall, i.e. the feeding spot. It then waits for half a second to feed after which it returns. The important part here is that students should calculate the total number of pre-set rotations by adding the number of rotations to the first feeding spot and the number of rotations for the 90-degree turn. So, if the robot has to go forward for 3 rotations until it reaches the feeding spot and then turn for 4 rotations, the "magic number" is 7. In order to return to the first feeding spot, the robot should move backwards until the rotation sensor gets back to the value we calculated. In our example 7 rotations, as shown in the picture below.

To access the full video please subscribe to FLLCasts.com
- #1123
- 14 Jan 2019
Courses and lessons with this Tutorial
This Tutorial is used in the following courses and lessons

Level D1. "Animals". Robotics with LEGO
This is the seventh level of the Robotics with LEGO curriculum for students in third or fourth grade.
In this level students focus on the rotational sensor that is part of every motor in the robotics set.
Robot constructions imitate animals and their behavior. Students create programs that check whether the robot's claws or pecks have successfully caught an object. That sensor in the motors allows the robots to go back in their lairs even after the use of unlimited movement.
- 23
- 0:00
- 102

Lesson 2 - Fish
Introduction
In this lesson we are going to build a fish robot.
Have you ever been fishing? Have you seen live fish? Where?
Just like the fish on the picture, today’s robot lives in a coral reef. As many other fish live safely in the coral reef, just like ours, there is not much food left there. Therefore, our task today will be to help the fish robot search the region around its home and find some food.
- 3
- 4
- 3
- 3d_rotation 1

Robotics with LEGO - Level 2.5 - Maritime Journey
The fourth level of the Robotics with LEGO curriculum for students from fifth to twelfth grades.
In this level students focus on the rotational sensor that is part of every motor in the robotics set. Students also learn to use the fourth sensor in the robotics set - the gyro sensor.
First few robot constructions imitate sea-animals and their behavior. Students create programs that check whether the robot's claws or pecks have successfully caught an object. That sensor in the motors allows the robots to go back in their lairs even after the use of unlimited movement. The rest of the robots are modeled after boats, yachts, and ships. With the help of the gyro sensor, students can set a course for their robots to a given angle and can detect deviations from the course. In open seas, there may be sea-monsters and the robots are being programmed to detect a sudden change in acceleration with the help of the said sensor.
- 42
- 3:52
- 133