This is going to be my first year doing Vex robotics, and I’m honestly clueless.
I’ve made a simple clawbot before, but that’s pretty much the extent of my knowledge of Vex. I know how to code and whatnot, but the problem is with building. I want to make a dumpbot, but I don’t know how to start off. I don’t want to copy someone’s design, but at this point, I don’t have any ideas on how to start. It’s just me on the team right now, so I don’t have anyone who is able to guide me.
Are there resources that are available for me to learn about building? And what are some beginner mistakes that a lot of people make?
If you’re building a dump bot, https://vexforum.com/t/singapore-vex-robotics-championship-2016/35577/1 this thread (the singapore vex championship thread) should give you some inspiration. Try to reverse engineer some of the things you see in the videos, as things may not be as simple as they look. Once you’ve reverse engineered some of the stuff you’ll have a better understanding as to how you’ll want your dump bot to be designed.
General things I always keep in mind
-target each design towards a specific strategy
-Choose your strategies based off of reward vs. difficulty. Reward is based off of net points while difficulty is based off of needed repetitions
-Motors only supply about 2 inch pounds of effective torque without tripping cortex’s or ptc’s safely (without gearing/internal gearing for speed or turbo). This limit will change based off of how long the robot is running, so pushing your designs are dependent on run time
-1/8 inch axles can only handle about 118 to 100 inch pounds of twist and/or about 10 inch pounds of bend before they start to permanently deform. Because of such, reinforce them or let them slip as needed. To find out, perform a torque calculation (torque=Force*distance to center of gravity)
-Strive to make robots as compact as possible. This will naturally lead to rigidity, which is super critical
-Rigidity of a robot isn’t just to survive matches. Rigidity is critical in keeping all variables of game piece manipulation constant. Because of this, reinforced tuning is critical in designs (can you adjust the height of a scoop, the width of a drivetrain, the pressure of a roller, the size of the claw, etc.)
-Take code in small steps. start with what you know, then prove whether or not you know it. If you don’t know it, then review what you do know and go from there. Breaking up the problem helps a lot
-At the bare minimum, always have a drive forward autonomous
-Leave lots of comments and make naming clear for everyone
-Make multiple copies of the code
-When improving code, comment out old code just in case the new one messes things up
-Tie up your wires neatly. Greatly increases the reliability of your robot due to less entanglement risk
-Plan ahead on where you want to place your cortex so it’s easy to check wiring for code. But also make sure it’s protected
-Use the wire clips or zip tie the cables together
-Try to modularize motors. If they’re easy to take off or easy to tighten, then it’ll make competition so much less stressful
If you want, you can message me, and I can help you throughout your season. I always enjoy helping out the beginners
We have some new guys in our team too, and they started by making a clawbot also. The first thing they did while building is making a drivetrain, then programming it. After the drivetrain, work on the accumulator (intake/conveyors), then program it. Next, try to find a way to shoot the stars, or find a way to dump them.
My team’s approach to building is to start off by prototyping different types of bases and arm systems, then we will proceed to build the base then arm finally the mechanism.
Building in 3 seperate sections will allow you to better visualise the amount of space you have to work with when building the arm or mechanism i hope i helped, if you have any enquiry on vex engineering please feel free to reach out to me, though i may not be always around on the forum
Just to add onto what everyone else has already said, I’d start by building a reliable drivetrain, that way, if need be, you can always compete in earlier competitions as a push bot and still be partially effective. Then, over the season, you can build onto your, ‘standardized’ base and switch out attachments while always having the drive to fall back onto in case something doesn’t work.
We maintain 8 clawbot kits. Every new team member must build a clawbot before they are allowed to work on a competition bot, they work in pairs to do this. We use the clawbots during open houses and other demos throughout the year as well as practice matches. They are great for practice matches, to get used to having multiple robots on the field. They are great for outreach; we let almost anyone drive our clawbots around at demos. At the end of the season, the clawbots are dismantled and put back in small husky tool boxes for the next crop of newbies.
Do your homework. As said above decide on a basic design and make sure you have a reliable drive train. Watch lots of youtube videos and determine what style is best for you each season and work hard in the beginning to make sure your drive train is as close to 100% as possible. A reliable push-bot is way better than a stationary bot with a reliable upper body.
Build a prototype base to practice with while you build your competition bot. There is no substitute for driving experience. Our drivers practiced for weeks at the end of the school year with our prototype bases long before we had game elements for Starstruck. They already have a solid understanding on what wee need to do for auton programming and how the final bots will move on the field.
If you need proof, just look at the beautiful driving of 1104 bots at worlds this year. They were the best driven bots and the reason they had 3 in the final. Also big shout outs to 400X, 2587Z, and 118. Their drivetrains have been set early in the season year after year and the reason they have been perennial contenders at the highest levels
It is ok to take inspiration and assets from different bots without completely cloning it. Some common beginner mistakes are like going straight to the build with no design and beating yourself down because you think your bot sucks. Sure your bot might suck but, It’s like your first or second bot. Just think, most other people you know probably have no clue as to how you build a robot.