What would be better a single or double flywheel? I had a vertical double flywheel and did not work out to well. I want to be able to shoot in the high goal and do not know what would work better. Suggestions?
a properly built dual flywheel can be quite deadly, and single flywheel launchers are too inaccurate
I think you have the opposite there… Many good teams are using single fly wheels and if you build it with the right compression and the least amount of friction you can have, it will be very good
@ThunderRobotics single flywheels have more tendency to fire to the left or right, whereas a dual flywheel(both sides mechanically linked) does not have this problem
I have seen both properly built single flywheels and properly built dual flywheels do well. However, when a single flywheel does well it typically does better than a dual flywheel. Also, I see very few well built dual flywheels in comparison to well built single flywheels, and while I am not positive on why this is, it could mean that a well built dual flywheel is harder to build than a well built single flywheel.
I’ve only seen two single flywheel launchers, it seems nearly every team in Florida is using dual flywheel launchers, also the two teams in top 30(trinity dragons and skull n bones) have dual flywheel.
Yea we have 3 single fly wheels at our school… 2 base shooters and 1 field bot. The 2 base shooters have very good accuracy and the field bot is so close to the net when it shoots it doesn’t miss
Single flywheels have a higher theoretical fire rate. With most single flywheels, the launcher uses a 28:1 or 25:1 (or even 24:1) ratio and at least 4 motors. With a double flywheel, each side only has half the motors. Therefore, to match the fire rate, the double flywheel must have a gear ratio of 14:1 or lower. Since most double flywheels actually have gear ratios closer to 18:1 at minimum, single flywheels can theoretically fire more balls per second.
Then there is the issue of accuracy. Both designs can have killer accuracy if designed correctly, but neither “usually” has great accuracy. The easiest way to increase accuracy for both designs is to improve the compression rate. Try this: take 3 very squishy balls and 3 very dense balls and fire them. If the squishy balls go farther, decrease the compression rate. If the dense balls go farther, increase the compression rate. At some point, the compression rate will be balanced such that all balls travel the same distance. Once this is accomplished, both single and double flywheels can theoretically launch basically all 24 preloads into the high goal, or at least at exactly the same target.
For these reasons, I prefer single flywheels. However, a number of teams such as the Cyber Brains have achieved very impressive fire rates with double flywheels, so I can’t say that single flywheels are definitively “better.”
Good luck!
We have learned that either flywheel will work with enough tuning. We have double flywheels because they don’t require hardly any motors to achieve the fire rate and accuracy that we want. In the end, it’s all up to how well built the launcher is, programming, and user skill (loading and driving).
If both are built properly, both will work similarly. Logic says that single uses more energy per shot (spins ball and creates a sharper arc because of the Magnus effect) but it is minimal in most cases and energy loss is normally more due to improper construction.
I would say chose the one that better compliments your desired design as a hole. We chose a dual mainly because it fit well in our design.
I don’t think your logic is correct here. 2 Smaller systems can have the same energy as 1 more powerful system. You still have 4 motors of power. 18:1 is probably too low to easily achieve a full court shot.
We originally had a double flywheel, it worked great, and was accurate, but recently we switched to a single flywheel, and it is working a lot better than the double flywheel without any tuning.
Can someone post photos or video of the difference between single and double flywheel. We are a new team and can’t get our double flywheel to shoot far enough. We are also having problems with stability of the gears. [attachment:56a597cdb732b]
Wow, nice system. I think making the gear ration higher is the best you can do for range. Maybe add another 2 motors?
There are lots of different robots
The stability issue is because the gears are cantilevered (supported only on one side). I would also suggest adding two motors and checking for friction.
Like the intakes on toss up robots? Maybe adding another c-channel and bearins would help?
Less like the intakes and more like the lifts, but support the gears both on top and below.
So far this season our team has been using single flywheels, and they seem to be working great. However, they have quite a lower fire rate than the punchers unless you implement a velocity controller for the wheel(s), such as a PI/PID controller. Also, for the one wheel, make sure you have the right compression of the ball because it will influence the velocity, accuracy, and spin of the ball.
Hope it helped 
Our team 1115D has been using dual flywheels and and a test off 100 balls made 95 of them in the high goal from firing at the low goal. If you do not have backspin we have found it is never accurate. Also use a slow motion camera to see if you are wasting energy.
I use a 5in Single flywheel. We get the occasional issue with weird density balls (like more weighted on one side) but otherwise are near perfect accurate. We got compression right and have a TBH controller with autofiring ability. Backspin is the key when aiming for the back of the net, otherwise they bounce wildly. The oddballs we find tend to fire to one side or another by about 10 degrees and they come out of the “barrel” (basically two plates which follow the ball for some of the flywheel contact ) with some side and back spin.
From what i have seen in my area, Double flywheels are possible, but are very inaccurate unless both sides are chained together. and even then. unless they are at a high angle with low power, they lose most of the balls due to mechanical issues between the two wheels. Most of the single wheels in my area are very accurate, minus speed recovery due to a lack of programming expertise.