This week, the team completed their second Preseason Design Challenge. The objective was to design a shooter that can shoot a 12 inch ball at a 7 foot high hanging target.
Group 1- Piston Punch:
The "Piston Punch" mechanism is based around the ability to hit a target that is suspended 7ft in the air with a hard ball that has a diameter of 12 inches. To achieve this our shooter uses pneumatics. It uses one central piston with a large flat circle mounted between two arms that propel the ball forward once the piston is powered. The shooter is able to adjust its aim by changing its throwing angle. This angle is adjusted through the use of two gearboxes connected by a chain. When one of them runs, it causes the chain move the other gearbox. On the ends of the arms is a 11.5in by 11.5in piece of lexan with a 6.5in hole in the center of it, dubbed the "basket". In addition to this, it has 4 nine inch tall arms made of 1in by 1in pieces aluminum tubing that function to hold the ball in place wile the shot is lined up.
Group 2- Crossbow Shooter:
This design has a crossbow-like system used to shoot the ball. There is a square frame that serves to guide the ball's directions and a carriage to hole the ball. Bow strings are connected from the front of the frame to the carriage to launch the ball. In order to create tension in the bowstrings, an Evo Shifting gearbox is used to pull back the carriage and create the tension necessary to launch he ball. Once it's ready to launch, using pneumatics the gearbox shifts into neutral and lets the carriage go free. There are a few cons with the design. The cost would be in the $400 range and there is a decent amount of aluminum tubing needed to make it. Along with tubing we would need the crossbow wires that connect to the carriage. It also requires multiple brackets and gussets to assemble. Electronically, there would be a need for a motor controller and encoder to know how far the carriage has been pulled back.
Group 3- Catapult Launcher:
This design utilizes two pneumatic pistons to power a set of arms that launches a ball 7 feet into the air and toward a target. Pneumatic pistons are tube-like parts that have a slider inside and is extended and retracted using compressed air. The use of pistons allows each launch to be identical, increasing consistency and accuracy. The pressure from the pistons is able to create enough force to rotate the arm 90 degrees on its axle. When the arm reaches its maximum height, it will launch the ball with enough force to hit the target.