Godwin Robotics was graced with the opportunity to build a robot representative of the ideals of FIRST: the Ambassador Robot (AmBot).
The AmBot was to be a robot of suitcase size that FIRST officials could tote to elementary and middle schools for demonstrations. At these demonstrations, children could learn about the importance and enjoyment of robotics.
Although small, the AmBot presented a number of obstacles that needed to be overcome in a short amount of time. We decided to have the robot shoot small, Nerf balls to display some of the tasks that a robot could perform. Our first notion was to shoot the ball with a small motor mounted on a PVC tube. Unfortunately, we did not have motors fast enough to propel the ball. Our next idea was to use air pressure. We hooked the shop air up to a PVC tube at the closed end and stuffed a ball down the tube. To our contentment, the ball fired!
Although the mechanism worked, Mr. Hurlburt wanted a hopper system to hold many balls that could be fired one after another. After many failed designs, the air shooter idea was dropped. Just when all hope seemed to be lost, a catapult idea was brought to attention. We attached a long piece of angled aluminum to a door hinge and used surgical tubing to produce tension. We then mounted a piston in front of the hinge-tubing apparatus to push the aluminum piece down and to release it. We quickly discovered that since the motion of the piston could be controlled, surgical tubing was not necessary. This design shot the ball a good distance.
During the process of building the hopper to load balls into the shooter, it was discovered that timing the actuation of the servo (which would release the balls into the catapult) was difficult and that the shooter only worked well with shop air pressure, not compressor air from the robot itself. With this dilemma and with build season right around the corner, we enlisted the help of mentor Mr. Rick to help build the shooter. His design went back to our first one: the one with the motor mounted on the PVC. This time, a much faster motor was used. He ingeniously used a hopper built into the shooter with a piston to push the balls into the wheel mounted on the motor. We took off the catapult mechanism and attached the Rick Shooter, which worked wonders. The AmBot is currently being fit with lexan to make it safer for the demonstrations. We at Godwin Robotics cannot wait to present our finished product to the FIRST community.
AMBOT PICTURES