Rocker Bogie Robot Kit

The 2021-2022 FTC Season Freight Frenzy had an uneven playing surface. The Barrier created a challenge to go around or go over. 

There are lots of ways to approach this problem. Some teams investigated the Rocker-bogie suspension system (https://en.wikipedia.org/wiki/Rocker-bogie). There are two keys to this design. The first is that it steadies the vehicle body relative to the motion of the wheels and terrain.  The second is  that it allows travel over obstacles that are up to twice the diameter of the wheels.

Teams did discover that creating a Rocker-bogie suspension is more difficult than it appears. I recommend starting with the Bogie Runt Rover kit (https://www.amazon.com/Actobotics-637162-Bogie-Runt-Rover/dp/B00UZMJ2BQ). 

The kit is just the robot chassis. It can be controlled by any number of robot controllers, like an Arduino or Raspberry Pi. In 2021, in response to COVID-19, FIRST and WPI developed software libraries used with the Romi chassis and Raspberry Pi controller (https://docs.wpilib.org/en/stable/docs/romi-robot/index.html). This may be a good place to start with building out a Rocker-bogie robot.

After gaining experience with the rocker-bogie suspension, he team will be better able to decide if it is the best option for their competition robot design. 

The Bogie Run Rover kit can also serve as a demonstration robot to take to Outreach Events. Many people have seen this design in videos of the Mars rovers, but have not seen one up close.

Remember that there are many good solutions to any given problem, like traveling over the Barrier in Freight Frenzy. During the Engineering Design Process teams need to identify as many possible solutions as they can and then compare each of these potential solutions to find the one that is best for the team's strategy and based on the team's skills and resources.

Comments

Post a Comment

Popular posts from this blog

FRC 4414, High Tide, Pit Writeup

 Check out this Pit Writeup on Chief Delphi: https://www.chiefdelphi.com/t/team-4414-hightide-pit-writeup/411862.  This provides a great example of how to design and improve a pit. I've been interested in road cases for use with pits since I volunteered at my first event and saw that this is how FIRST transports the field from venue to venue. The High Tide team has worked with a road case company and developed a great pit. The pit is your home when you're at an event. There are enough other things going on during an event, so you want your pit to be familiar. I recommend setting up the pit every meeting at your home workspace. You may have more equipment or additional work tables at your home base, but you should keep your tools and parts in your pit during regular meetings. This way everyone knows were to find things when you load in your robot and are setup for an event.
Read more

Museum Robot Exhibit

I was recently at the Indianapolis Children's Museum (https://www.childrensmuseum.org). It is like no other museum. You have to check it out. The good news is you don't need children to enter. I grew up in Indiana and have fond memories of going to the top floor to the Science Exploration exhibit. Unfortunately all the cool physical science experiments which were there when I was a kid have been replaced with an Agriscience exhibit. I'm not taking away from the importance of Agriscience, and it makes sense that a museum in Indiana needs to highlight this critical area. I just wish it could live in harmony with the old science hands on area that I remember. Ah-ha! Why did Dean Kamen choose robots when he wanted to inspire kids to pursue careers in science and technology? The reason was because robots cover everything. There are mechanical parts, electrical parts, pneumatic parts, and software. There are small robots for young kids and big robots for kids and adult mentors. W...
Read more

Driver-centric or Field-centric

The terms "Field-centric" and "Driver-centric" are used interchangeably in FIRST robotics. I think we need to differentiate them. I also think we need to use them properly. This drive system is common in both FTC and FRC since both have teams building holonomic drive systems. In FTC, Mecanum wheels are popular since defensive play is limited by the rules. In FRC, there are some teams with Mecanum wheels, but there are more teams building Swerve drive systems. Both terms are used to refer to a control system where when the Driver moves the control input to the right, the robot moves to the right from the Driver's point of view. Since the Driver is in a fixed position on the field, the robot moves to the right side of the field.  This control system is in contrast with a Robot-centric control system, which is where most teams start because it is easiest to understand. When you move the joystick forward, the robot goes forward, no matter which direction it is facin...
Read more