Intake RPM

[Knufire]

I'd echo making sure that you have enough power on it.

469 in 2012-2013, and most of 5188s intakes were a 2" roller on a 550 or 775 motor at roughly a 5:1 reduction. The power of a 775Pro makes it great for this application.

[aphelps231]

We used a BAG motor on a 9:1 Versa Planetary and switched to a 10:1 for champs. This gave us a wheel speed of about 13fps on our 2" wheels.

I would not run this setup again. The BAG motor tended to stall out when intaking the ball from the side (we ran 2" mecanums on the outer rollers), and the intake was a little slow. A 775pro would have been much more beneficial, as well as faster (speed was the big issue since stalling was fixed by tuning compression).

A handy tip for anyone looking to increase the performance of their mecanum intake: set the intake to have about .75 to 1" of compression, and allow it to be pushed up by the ball when intaking. We achieved this by using an in line pressure regulator to limit the extension side pressure of our pistons on the intake. Although it could be done with code adjusting your Kp value in PID (while intaking == true && the intake position is in a certain range with the lower bound being full extension and upper bound being 0" of compression) if you're using a motor with an encoder to move your intake.

[Cash4587]

I've attached the intake calcs for my teams robot this year. Our robot was geared for 14.5 fps so our intake was geared according. We spent weeks upon weeks testing on what intake was the fastest and best and came out with 6, 4" mecanum wheels (3 on each side) and 2, 4" stealth wheels in the middle. Our intake was very very quick. We took inspiration from 118 and worked with them a bit to understand how theirs worked.

As stated earlier in the thread, 2x your robot's ground speed is a good start for your intake speed. We then also threw power at it. We used 2 versaplanetary each with a 775pro to power our intake. We put about 1.75" of compression on the ball to grab it but when the ball came into the robot it would compress down from about 10" to 4" to get into our catapult. We had no issues with jamming or anything all season.

Here is some video of it in action.

https://www.youtube.com/watch?v=Y13rcqgDcBU

[ns3517]

Originally Posted by bkahl

Maybe not 2x, but gearing a linear speed of an intake faster than the drive allows you to intake while the robot is moving in any direction. Just gearing faster than the drivetrain is a better rule of thumb.


NS3517,
I don't think you're asking the right question.

The RPM of any intake is not a good measurement, because the same RPM on different rollers provide for different performance.

The most important factor of the intake is the Linear Speed, as Adam described in the quoted post. The linear speed of an intake is independent of the roller diameter, and is a better way to measure intakes across other robots.

As for motors, the 775pro is bomb.

You're right my bad

[BJT]

Our intake, which was also our shooter, ran a 775pro on a 5:1 versaplanetary at full power on both top and bottom rollers. To shoot high goals from the batter they were at something like 80%. rollers were 2inch blue andymark wheels. It was FAST. the ball just disappeared from where it was into the intake. made the whole assembly jump a little when it sucked one in

[AustinSchuh]

Originally Posted by RoboChair

775 pro all the things

front intake was 1800 rpm about 11 FPS surface speed

Bah, that's slow. We ran closer to 25 FPS, and that was the right answer this year. I've been going for 1.5x-2x the robot speed. (I don't keep track of RPM since it doesn't matter). We actually started running 775 Pro's this year over-geared, and then just running them at 70% PWM to reduce the power draw.

It is always a balance between sinking a bunch of power into the roller on stall or normal operation, and waiting on the intake. You don't want your intake to starve the rest of your robot of power.

[IKE]

Has anyone tried doing smooth belt drive like a Vacuum cleaner beater bar?

[gerthworm]

single bag motor, geared with our wheels to provide a 20 ft/sec travel speed along the polycord intake. Definitely slower under load, not sure by how much though.

[AdamHeard]

Originally Posted by AustinSchuh

Bah, that's slow. We ran closer to 25 FPS, and that was the right answer this year. I've been going for 1.5x-2x the robot speed. (I don't keep track of RPM since it doesn't matter). We actually started running 775 Pro's this year over-geared, and then just running them at 70% PWM to reduce the power draw.

It is always a balance between sinking a bunch of power into the roller on stall or normal operation, and waiting on the intake. You don't want your intake to starve the rest of your robot of power.

This guy knows intakes.

Listen.

[JesseK]

We did a BAG motor through a VP 7:1 then to 4" wheels. The gearbox setup was a lot like 1678's 2014 bot - chain-in-tube, and very easy to swap gearing around since the VP gearbox was so exposed. It also allowed us to completely change the intake geometry without worrying about what gearbox to use.

It was pretty speedy (red robot on the bottom at the start of the match). Never stalled the intake or threw the chain. Used 4 Mecanum wheels on the intake axle closest to the bumpers.

[Tom Bottiglieri]

Originally Posted by AustinSchuh

Bah, that's slow. We ran closer to 25 FPS, and that was the right answer this year. I've been going for 1.5x-2x the robot speed. (I don't keep track of RPM since it doesn't matter). We actually started running 775 Pro's this year over-geared, and then just running them at 70% PWM to reduce the power draw.

It is always a balance between sinking a bunch of power into the roller on stall or normal operation, and waiting on the intake. You don't want your intake to starve the rest of your robot of power.

Our intake had an over-geared 775 Pro as well, and we found any stall condition would pop breakers really fast (compared to older motors). We ended up running our intake under current control mode on the Talon SRX to artificially cap the current draw. This caused the roller to run at 100% voltage/speed while unloaded, which was fine for our application. This also had the nice property of working like a software clutch.

It would be cool if the Talon had a current cap mode that still allowed variable voltage control.

[IKE]

Originally Posted by Tom Bottiglieri

Our intake had an over-geared 775 Pro as well, and we found any stall condition would pop breakers really fast (compared to older motors). We ended up running our intake under current control mode on the Talon SRX to artificially cap the current draw. This caused the roller to run at 100% voltage/speed while unloaded, which was fine for our application. This also had the nice property of working like a software clutch.

It would be cool if the Talon had a current cap mode that still allowed variable voltage control.

I was curious how the folks running superfast intakes and 6 cim drives were keeping their main breakers intact. IE, stalling an intake often can occur around the same time as stalling drives when trying to "dig a ball out of the corner".

[Gogoyogert]

We used a mini-CIM with a 4:1 Versa Planetary on it. A mini-CIM is 6200 RPM, so our intake is at 1550 RPM. We didn't try anything else but our intake seems to work very well.