February 5, 2016
Week 4: Mechanical Construction
Mechanical Monarchy, the FIRST Robotics team from Washington, Illinois, sees versatility as the key to success in this year’s FIRST Robotics Competition. Members, with the guidance of their invaluable mentors, have spent hours collaborating on, designing and constructing the ideal mechanisms to accomplish their goals for this season’s robot.
After thorough review of the numerous different challenges that came with this year’s medieval-themed game, and after hours of collaboration and strategic planning, Mechanical Monarchy chose to place special emphasis on a robot that could score points by (1) shooting in both the low and high goals, and (2) breaching the majority of defenses. Achieving these tasks would require a set of versatile mechanisms.
Crossing the defenses includes various terrains, but the team realized that if they focused on the mechanisms necessary for just three of the defenses – the Cheval de Frise, the Portcullis and the low bar – they would result in a foundation that could cross most others. The Cheval de Frise consists of four independently tilting platforms, requiring an agile drivetrain. The Portcullis is a tall, arched gateway with a door that opens when lifted by the robot, requiring lifting capacity. The low bar’s distinctive shape, with an opening just 16 inches high, would require a unique body shape. Because of its demanding dimensions, the design team had to determine the trade-offs for choosing to cross this defense. Although limiting, it forced the team to innovate creative solutions to package all mechanisms into a small overall design.
While crossing the defenses is critical for success in the game, when it comes to scoring points, throwing boulders is where it’s at. With each boulder scored in the high goal, a team can earn five points, while the low goal scores only two points. Constructing a mechanism that shoots in the low goal is much less demanding as the high goal requires both additional accuracy and consistency. But the Mechanical Monarchs are undeterred! The team has encountered several challenges while trying to create a catapult prototype that satisfies these shooting requirements. As one example, a prototype catapult that propelled the boulders using surgical tubing did not perform consistently due to the permanent stretching of the tubing that occurs over time. Several other factors had to be considered in this catapult, such as how the boulder would be held, where the pivot points would be placed and the amount of force needed to shoot the boulder.
The team’s strategy of successful shooting is also dependent on having a quick, simple and reliable mechanism for picking up boulders and moving them into the shooter. Because Mechanical Monarchs are only in their second year of competition, the students conducted research on how teams have successfully manipulated ball-like objects in previous seasons. The team researched previous ball-related games and sought out the top performing robots of those seasons. Their research led them to adapt an intake solution used previously by another local team.
In addition to the incredible problem-solving skills required to tackle each new challenge, the students are learning the hard skills of machining, welding and using CNC (Computer Numerically Controlled) equipment. The FIRST Robotics build season is an adventure in hard and soft skills, such as critical thinking and teamwork. With the help of their mentors, the student members of Mechanical Monarchy have also learned that versatility is exactly what is required of Caterpillar engineers who are developing our machines to satisfy the needs of a wide variety of customers.
About Mechanical Monarchy
The Washington Community High School Mechanical Monarchy Robotics Team is competing in their second season of FIRST Robotics. The team has doubled in size and added a JV team since last year. There are 30 students on the varsity team and 17 freshman on the JV team from the Washington area, as well as a homeschooled student. Mechanical Monarchy is mentored by eight Caterpillar engineers, three staff members and five adult mentors from other area firms. Following the build season, they plan to compete locally at the Caterpillar-sponsored Central Illinois Regional hosted at Bradley University on March 16-19, as well as the Iowa Regional in Cedar Falls, Iowa, on March 23-26. Like all of their peers around the globe, the ultimate goal of team is to earn the right to compete at FIRST Robotics World Championship on April 27-30.