Hi, I have seen that there are multiple threads on lifts and launchers but the major problem that hasn’t been addressed is how you will get the ball to your launcher. Personally, I see that using your launching motors to double as intake motors will be ineffiencent. Since this year everyone will be fighting for the balls and in theory you have less time to score because of last 30 seconds for lifting you will need a fast intake system that will work well with a quick to aim and shoot launcher. The only idea I can think of that will work would be to put intake rollers on the front, left, and right sides to minimize the time needed to get the balls. Anybody have any ideas?
So in some of the threads, people have referred to videos of robots from the FIRST robotics competition during the 2012 year. The game they played was rebound rumble and it was heavily based off of basketball. You could look into some of the robots and there designs for intake ideas. My personal favorite is a double sided intake where the ball can be grabbed from the front or the back or the robot. Not all 4 sides because it can get disorienting. The idea is to pick and load the balls rather quickly so they can be shot at the goals in a fast amount of time. Its a good idea for the intake method to be fairly tight against the ball to ensure a constant contact the whole way thru the robot. I also recommend an intake that is compatible with the human loader. But for more ideas, refer to looking up past robots.
There also was an FTC game played in 2009 named Hot Shot. There’s a lot of similarities that could assist in your ideas.
I was thinking tank treads with flaps on them. If you spaced the flaps correctly, each pair of flaps would hold one ball. You would have one tread on each side, this would allow you to intake it and roll the treads to insert the ball into your launching mechanism. Some argue that they might be too slow, but you can definitely gear your set up to be fast. Also, to help better intake the balls, you could put a side roller on the same axle as the bottom sprocket as to help better intake the balls themselves.
I had an idea for an intake (I would appreciate any advice those would be willing to give). What if you used a single intake wheel on the bottom of the back of your robot to pull the balls into a tube shaped structure in your robot. At the bottom of that tube shaped structure could be a tank tread with flaps which pushes the balls up at a 45 degree angle where they would be launched when they reached the top by wheels that spin incredibly fast. This is what I came up with without ever having seen the balls or built a prototype, so I’d appreciate any constructive tips.
Put the flywheels as close to the floor as possible. Then you wouldn’t need a long tread - just one roller that rolls the balls up to the flywheel booster. Flywheels have many advantages like simplicity, continuous (non-cycling) operation, high rate of fire, etc… Their only disadvantage is that slight imperfection in roller or ball surfaces or rotation speed hiccup could send the balls off center. So… definitely implement your tube idea similar to the cannon’s barrel - it will ensure the ball will leave it in the predictable direction.
Ok. Thanks for the advice
What our school is prototyping right now is long side rollers to intake the balls then have regular side rollers that are geared really high at the back to launch the balls
After actually prototyping a flywheel, our team has seen that any intake/flywheel loading mechanism needs to regulate the rate at which the balls are shot. The moment a ball is launched, the flywheel slows down considerably. If the next ball is launched immediately after, it will go a significantly shorter distance. So, to maintain consistency, either a slower intake or a loading regulating system is required.
That is a very good point. What is the weight of the ball you are launching? How many motors and flywheels do you use?
When our team brainstormed the launcher we settled on the four motor design. First motor will drive two intake threads. Second will send the balls one at a time up into the launch tube, giving it some preboost. And, finally, two booster motors will accelerate the balls with two flywheels to the full speed.
You can see our test with a Clean Sweep ball here.
We have imagined a similar set-up. One thing you should be wary of is your ball having too much speed when it hits the final flywheels. In our tests when we rolled the ball at the wheels too fast, the momentum caused the ball to actually climb up the flywheels before it got shot, messing up the launch. I suppose an easy solution to this would be to have a tube around the ball to keep it from climbing.