Hello!
My team’s struggling a bit with making a shooter, so I wanted to ask, what configuration are you using?
I.e. how much compression, length of hood, motors and gearboxes, etc.
Thanks!
Tamir Cohen.
Have you read any of the open build threads, Ri3d content, and the other shooter threads? I am sure there is enough information in those to answer your questions.
If they don’t, what parts of the shooter are you having troubles with?
And for what you asked. Most people are going between 1.5 - 2 in compression, a hood that’s around half a circle (sometimes less), falcons/neos, gearboxes are usually custom or just 1:1.
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We’re using 2” of compression on a 1/16 aluminum hood powered by 2 NEO550s on a 1:1 VersaDM gearbox. It takes around 9 seconds to get to full power.
Are you sure it’s 9 seconds? Seems awfully long. Our dual 775pro geared 2:1 gives about 300ms maximum to spool up.
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We’re using 4" 60a compliant wheels at the moment, on a 1:1 ratio of 2 falcons. We have some steel discs from McMaster, but steel gears work as well (but they’re expensive dont use them if you don’t have them). We’re running the pretty normal 2" compression. Hood length is going to depend on your release angle and where you feed from (generally either bottom or front). Depending on your setup, I’d check out either this calculator or this one.
I’d also check out RI3D teams, and other team’s build blogs for their testing.
But at the end of the day, you’ll get the most accurate information from your own testing.
We are using a 2 piece adjustable hood with 2 inches of compression, it is powered by 2 neos and adjustment is controlled by a 775. Making a one piece non adjustable shooter isn’t too difficult it just limits where you can score from on the field.
We’re only looking at shooting from directly under the goal, so 1" compression with a Neo at 65% and 15 degree exit angle is about right - although that is subject to further testing. But I suspect you want to shoot from further out, in which case you should be prototyping both two wheel and one wheel shooters. Based on our prototypes, a twin-Neo at 1:1 will hit the target from behind the wheel of fortune, assuming you can aim accurately. As far as I understand, you will need to double the RPM to get the same range with a single-wheel design.
The real issue was working out the strategy, as then we just had to design a shooter to match. Getting the range was not a major concern.
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Yes, it takes around 3 seconds to get to 6000rpm and around 5-6 seconds to get to 10000rpm
Shreykv,
Are you using PID to get to your desired RPM? I think it could be much shorter. Also, at 1:1 how are you achieving 10,000 RPM with Neos?
I don’t think we have, that’ll be something we have to look at. We’re using the 2 NEO550 for our shooter.
Oh - sorry - I was thinking Neos. Do the 550s recover well after a shot?
Ye, when you run your motors at 100%, you’re not in the optimal power band and recovery takes forever. You may want to consider alternative motors or gearings to achieve a faster spin up.
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You might have your programming team use the Spark Max Client PID configurator and try tuning your RPM ramp-up. Use the guide posted above as to how to approach tuning. You should get much faster results.
It usually takes 1> to recover, pretty fast.
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Hello @anon12642235. We are also using dual 775’s and having trouble. Can you take a look at this link, and possibly compare your flywheel, shooter diameter, and wiring conditions?
How much voltage drop are you guys getting?
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