When we are assisting in a class, and have more than one Robot available, we often use a “SUMO” Challenge. Students seem to love these contests, which also gives them an opportunity to let their imagination run wild when building their SUMO robot.
See three SUMO bouts between Student enthusiast’s EV3 SUMO Robots.
Potential Problem When Using Four Large EV3 Motors
You will notice that in the third SUMO contest in the video above, two of the teams combined and produced a SUMO robot that used four large EV3 motors. In the program below, the reason for the first “Move Tank” command having speed settings of +50, and the second “Move Tank” command having settings of -50, is that the second set of two motors (C and D) were mounted backwards, and had to use minus speed settings so that all four motors were sending the SUMO robot in the same direction.
In their initial program, the students used two “Move Tank” commands inside the loop, as shown below. THIS DID NOT WORK!
Solution When Using Four Large EV3 Motors
The students found two programs that did work; see below:
This one used one “Move Tank” command for motors plugged into slots A and B, and two “Large Motor” commands for motors plugged in to slots C and D.
This program used four “Large Motor” commands.
The students then went on to modify the second of these programs to cope with the black lines around the SUMO ring, and then entered their Robot in the SUMO contest. You can see their result in the video above.
SUMO Ring Arenas.
For SUMO contests, we usually use any of our free down-loadable A1-printable arenas that have black surrounds, e.g SUMOV4, Alien-Arena-A1-V3, AlienA3V4 or Floor-Cleaner-Arena-V4. An A1-sized piece of paper or cardboard, with black paint or black electrician’s tape around the edges would serve just as well. Since all our arenas were being used elsewhere at the time, in the video above we used a commercially available MTA Robotics Training Mat purchasable from MTA.