Interesting/Cool Scaling Mechanism Designs

[JABot67]

This year has been an interesting year for scaling mechanisms as teams try to meet some very difficult design constraints. With many teams deciding to go under the low bar, the packaging problem that comes with a scaling mechanism can get very challenging. I wanted to create a thread to talk about all of the awesome "out of the box" ways that teams have solved this problem.

Obviously what comes to mind is 118's grappling hook - as far as I know we've never seen anything like that before.

But for my contribution I want to spotlight SWAG 4060:

https://www.facebook.com/swag4060/vi...02735356484448

Their scaling mechanism is a long inflatable tube with a hook at the end! It doesn't even look like they can scale until the last 20 seconds, when a giant tube unfurls out of their robot and attaches to the rung. Their hanger got them all the way to the finals at Auburn, but sadly they didn't get enough points to get to PNW Champs.

What awesome scaling mechanisms have you seen?

[Boltman]

As a low bot...ours was super compact, pretty climb and very fast when it worked and went all the way to top once too far.
Simple scissor with slots in top part instead of holes so top could center and pop off to winch up.

We used a winch connected to "collapsible coat hanger" part of the scissor and 2 Cims.
Had a wood box centering it.

https://www.youtube.com/watch?v=fF5at9wG0Ug

Successful QF scale in SD week 1 at end of clip.
We were alliance 8 they were alliance 1

One of our original designs was something either inflatable as in OP or with a spring like a snake, we spent lots of time initially looking a different options. Glad inflatable worked that is cool. Love its simplicity.

[Jared Russell]

Originally Posted by JABot67

https://www.facebook.com/swag4060/vi...02735356484448

[pwnageNick]

How does 4060 ensure that as the balloon thing collapses when lifting up, that it stays within the 15" extension zone?

It doesn't look like it sticks too far out in the video but also seems like it could potentially end farther out.

I'm sure they thought this through so I'm just curious as to how they're solving that issue. I would think some strong attached to the middle with a spring or something could guide it to collapse back into the robot.

[Roboshant]

https://www.youtube.com/watch?v=SDcDmt2Or70

Link to a match where both us (226) and 217 scaled. We have a multi-stage lift made using rev-rail, and is connected to a series of constant load springs. The bottom of the mechanism is attached to a winch. At the end of the match the driver reverses the winch, allowing for the mechanism to go up, and then brings it down to scale. We used 2 cims for the scaler, and a back drive gearbox with a servo. I'm not sure about 217's scaler, but I think it uses similar tactics with a lock to firmly grip the rung.

[GeeTwo]

Originally Posted by JABot67

But for my contribution I want to spotlight SWAG 4060:

https://www.facebook.com/swag4060/vi...02735356484448

Their scaling mechanism is a long inflatable tube with a hook at the end!

We had an idea like that but decided that it would have failed inspection under R77 and as clarified by Q688.

Originally Posted by R77

The only pneumatic system items permitted on 2016 FIRST Robotics Competition ROBOTS include the items listed below.

• A. Items available in the KOP (except as noted in R77-K),
• B. Pneumatic pressure vent plug valves functionally equivalent to those provided in the KOP,
• C. Solenoid valves with a maximum 1/8 in. NPT, BSPP, or BSPT port diameter,
• D. Solenoid valves that are rated for a maximum working pressure that is less than 120 psi rating mandated above are permitted, however if employed, an additional pressure relief valve must be added to the low pressure side of the main regulator. The additional relief valve must be set to a lower pressure than the maximum working pressure rating for the solenoid valve,
• E. Additional pneumatic tubing, with a maximum 0.160 in. inside diameter, functionally equivalent to that provided in the KOP,
• F. Pressure transducers, pressure gauges, passive flow control valves (specifically “needle valve”), manifolds, and connecting fittings,
• G. Check valves, provided that the requirements of R89 are still met.
• H. Shutoff valves which relieve downstream pressure to atmosphere when closed (may also be known as 3-way or 3-way exhausting valves).
• I. Pressure regulators with a maximum outlet pressure of no more than 60 psi,
• J. Pneumatic cylinders, pneumatic linear actuators, and rotary actuators,
• K. Pneumatic storage tanks (with the exception of White Clippard tanks P/N: AVT-PP-41), and
• L. Compressors compliant with R79.

Originally Posted by Q688

• Q.Are inflatable pool tubes allowed when using a solenoid to pressurize in the match?
• A."Inflatable pool tubes" are not included as pneumatic items that are allowed on FRC ROBOTS in R77.

Originally Posted by pwnageNick

How does 4060 ensure that as the balloon thing collapses when lifting up, that it stays within the 15" extension zone?

I don't know how 4060 did this, but we were considering a coiled wire or tube inside the inflatable that kept things from getting too far out of hand. Our first iteration would have been with a piece of lightweight dryer vent tube.

[Dave McLaughlin]

I was told while spectating 4060 at Auburn on Saturday that they fill the tube using a fan, separating it from the pneumatic system. I believe they 3D printed many of the components.

[GeeTwo]

Originally Posted by Dave McLaughlin

I was told while spectating 4060 at Auburn on Saturday that they fill the tube using a fan, separating it from the pneumatic system. I believe they 3D printed many of the components.

It looks like that homebrew compressor was pushing a whole lot more than 1.1 cfm. If you're doing work with air, it's a pneumatic device. (Noted exception for closed cycle air springs.)

[JABot67]

Originally Posted by GeeTwo

If you're doing work with air, it's a pneumatic device.

If this is true, then all fans and fan-blown vacuum devices on FRC robots are illegal.

It is unclear to me what constitutes a pneumatic device. Obviously nothing custom can be connected to the "canonical" pneumatic system on the robot, which is heavily regulated.

EDIT: Vacuums are legal per R77. Other things maybe not.

R79 Compressed air on the ROBOT must be provided by one and only one compressor. Compressor
specifications must not exceed nominal 1.10 cfm flow rate @ 12VDC.

Hard to argue that an inflatable tube hanger does not create compressed air.

[bennettj800]

so how does a 3d printed fan fill a cheapo innertube to extend...?
could this be the work of a secondary compressor? (it may very well be the same work of the one original with a solenoid allowing for a tank to empty into it... or something... :/

also, i dont know that its the most consistent way to hook onto the bar, seeing as it wobbles here and there when they do it...

(again, please let me know if i have the wrong thought train here...)

(like, please... pretty please)

[Cory]

Originally Posted by GeeTwo

It looks like that homebrew compressor was pushing a whole lot more than 1.1 cfm. If you're doing work with air, it's a pneumatic device. (Noted exception for closed cycle air springs.)

I love the confidence with which you make your clearly wrong statement.

[Navid Shafa]

Originally Posted by Cory

I love the confidence with which you make your clearly wrong statement.

I guess we may never know the answer to the age old question:

How much SWAG is too much SWAG?

[orangemoore]

Originally Posted by GeeTwo

It looks like that homebrew compressor was pushing a whole lot more than 1.1 cfm. If you're doing work with air, it's a pneumatic device. (Noted exception for closed cycle air springs.)

Custom Airblowers created from legal motors and fan parts are not constrained by the Pneumatic rules.

If you don't believe me please point to the rule(s) that prove what you are saying.

[bennettj800]

Rule R79:
"Compressed air on the ROBOT must be provided by one and only one compressor. Compressor specifications must not exceed nominal 1.10 cfm flow rate @ 12VDC."

this has already been pointed out...

also, a custom fan blowing a tube up (like a balloon) would be, in any circumstance, a compressor, thereby violating this rule. ergo, the custom fan has got to go if it is actuating something like it is.

[martin417]

Originally Posted by bennettj800

Rule R79:
"Compressed air on the ROBOT must be provided by one and only one compressor. Compressor specifications must not exceed nominal 1.10 cfm flow rate @ 12VDC."

this has already been pointed out...

also, a custom fan blowing a tube up (like a balloon) would be, in any circumstance, a compressor, thereby violating this rule. ergo, the custom fan has got to go if it is actuating something like it is.

For the purpose of FRC, a compressor is a positive displacement device.

Fans are legal per R29:

Hard drive motors or fans that are: included in any Kickoff Kit, distributed via FIRST Choice, part of a legal motor controller (including manufacturer provided accessories), or part of a legal COTS computing device

A fan is a fan, not a compressor. The rule does NOT say "a fan is legal unless you blow it into a tube", so don't try to create rules that don't exist,