EV3 Programming: Motor Blocks Continued

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Because motor blocks play such a large role in EV3 programming, we thought of some additional points to inform you about motor blocks. If you have not read our first article about motor blocks, you can find it here.

More About the “On For Seconds” Option

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The “on for seconds” option can be useful. For example, say your robot wants to ram into something and you don’t know exactly how far away it is. You can try to overrun your motors, but if the wheels can’t turn, the program can’t continue. This is because the motor block in the program cannot reach the number of rotations or degrees you specified. You can prevent this from happening by using the “on for seconds” option. If the wheels stop being able to move, the program will continue once the time is over. This strategy for the “on for seconds” block can be used for medium motors as well.

However, the “on for seconds” option is not perfect and cannot be used for everything. If you were to use the “on for seconds” option for everything, your robot would not be consistent. The EV3 and its programming software are not perfect and depending on the charge of your EV3 brick the movement of its motors will be slightly different. Do not fear! This change is small and this option will still work when ramming into things, it is just not ideal to use this option for all of your programming.

More About Turns

When doing smooth turns, your robot cannot move both wheels the same amount of rotations or degrees. For all motor blocks with unequal powers, the block uses the motor with the greatest absolute power to measure the specified amount of rotations or degrees.

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To test this, you can create a test program that will smooth turn until a stand-alone wait block measures a certain amount of rotations or degrees with a single motor. The first test, make the wait block measure the rotations or degrees of inner wheel of the turn. For the second test, use the outer wheel.

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For the third test, use a regular tank steering block. Have it match the powers and distance moved as the first two tests. Now, compare the first two tests with the third one. Which one was the same?

We hope you learned a lot! Thank you for reading our article!