We usually think of the ROBO-ONE robot competitions as being RC controlled robots, but there are several ROBO-ONE Special events where the robots are required to operate totally autonomously. The most interesting, at least to us, is the Ball competition. At first it looks simple enough. Pickup a ball from a post, turn around, take a few steps, and then throw it at a large bullseye target.
But, like most ROBO-ONE challenges, the Ball is much, much harder than it seems. The top robot builders put a lot of time and effort into designing special grippers to pick up the ball, and did their best to conquer the challenge. Still, very few of them succeeded, as you can see in the video below.
The Ball event regulations require that the robots gripper start off a minimum distance from the ball. Just getting the robot arm to move into position consistently, and to pick up the ball reliably is a major challenge. All of the robots managed to pick up the ball at least once, but some of them couldn't repeat the process consistently. As a result, they lost a lot of precious time.
Assuming that the robot actually manages to pick up the ball, then it has to turn around - usually a 180 degree turn, though some robots executed a 270 turn. Then they would typically take a few steps to position themselves in throwing position in front of the target.
Some of the builders seemed to depend on their robots ability to make repeatable turns and moves. As a result, a few of them ended facing either towards the audience or towards the judges on the side. However, some of them were equipped with magnetic compass sensors or cameras. One robot - Pento - was clearly equipped with a magnetic compass sensor that allowed it to line up dead square with the target before tossing the ball. If you watch Pento's attempt in the video below you can see the small alignment adjustments it makes to get into position.
After the event we talked to several of the builders about this. It turns out that the building where the event is staged in Kawasaki has some weird magnetic characteristics. Pento's builder, for whatever reason, has been able to figure out how to work around the problem, but it's still a big puzzle to many of the other competitors.
Finally, once the robot is in position, it brings back its arm and lets the ball fly. Often the 'fly' is literal. Several of the balls flew completely over the top of the target. Of course a few of them just seemed to drop out of the robots hand and dribble their way across the floor. There was even one very amusing case, also captured in the video, where the robots toss tried to take out the referee.
When all was said and done, Yokozuna Great Shiranui captured the top prize with a total of six points, King Kizer came in second with two points, and three other robots tied for third place with one point each.
While the Ball event doesn't generate as much tension and excitement as the Eagle or Dash events, still it's a lot of fun to watch and a great technical and development challenge, especially since the robots have to operate autonomously.