Rembrandt
Rembrandt was our first robot for the FIRST Robotics Competition. Just as we named our team after the famous Dutch painter Rembrandt van Rijn, we named our robot as a tribute to him, "Rembrandt". Rembrandt was built during the 2013 building season for the game “Ultimate Ascent”. With our robot "Rembrandt" we went to the North Carolina Regional in Raleigh and to the FIRST Championship 2013 in St. Louis. During the 2013 FIRST Robotics Competition season we won the Rookie All Star Award at the North Carolina Regional.
Our strategy with Rembrandt was, to build a robot that can pick up frisbees from the feeder station and from the ground, shoot the frisbees in the high goal with an angular movable shooter and at the end of the game to climb into the pyramid to level 1. For defence we added a net on top of the robot to block frisbees from other robots.
The Frame
Rembrandt is mainly designed and build of aluminium system profiles and there were a lot of custom made parts on the robot.
Compared with our other robots, Rembrandt was a tank. Rembrandt was very heavy, it even was too heavy when we were at the North Carolina Regional. Therefor we drilled and cut some holes in Rembrandt to get it within the robot specs.
For the drivetrain we chose a 4-wheel tank drive, with every wheel powered by a separated gearbox with a CIM-motor. In the middle of the drivetrain we build a modular electro box. By removing the bumper on the side and disconnecting the connectors, you could slide out the electro box.
Shooting Mechanism
On top of the drivetrain we build a vertically movable shooter. After some testing we decided to lock the vertical movement of the shooter, because our vertical movement wasn't accurate and strong enough to hold a position. Instead we used a fixed position at the pyramid. This made our shooting a lot more accurate. For the shooting of the frisbees, we use 2 pneumatic wheels and a pneumatic cylinder. Each of the wheels is driven separately from each other. The first wheel had more torque to give the frisbee speed and the second wheel spins with a higher speed to accelerate the frisbee even more. These 2 combined give the frisbee the perfect spin to fly straight in to the high goal. The pneumatic cylinder is used to transport the frisbee from the magazine into the spinning wheels. On our shooter we built a slide which we use to load Rembrandt full of frisbees at the feeder station.
Pick-up Mechanism
At the back of Rembrandt, we made a vacuum arm to pick up the frisbees from the ground and place them into the magazine. Unfortunately, the vacuum arm wasn't efficient enough. It took more time to fill up the magazine with the vacuum arm then go to the feeder station, load the frisbees and drive back. So, in the end we didn't use the vacuum arm.
climbing System
On the sides of Rembrandt, we have pneumatic cylinders with a hook. With these cylinders we can climb to the first level of the pyramid. We first designed Rembrandt to climb with spindles and an electrical motor. But this would take too much time and with pneumatic it works more than 10 times faster. On top of the hooks we mounted our net for blocking frisbees from other robots by driving in front of their robot.
Upgrades
After the FIRST Robotics Competition season we modified Rembrandt. We removed the vacuum arm, the climbing cylinders and the net. We replaced the polycarbonate slide for the feeder station with an aluminium version. Where the climbing cylinders and net were, we build a big partner sign with all our great sponsors and partners.