Mechanical

Converting Festo’s flow rate spec to Cv

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Festo gives the flow rate through their solenoid valves in terms of “standard nominal flow rate”. What does this mean? How does it compare with other valves on the market?

Here’s a spreadsheet that converts the specified flow rate (which is actually a mass flow rate even though it’s in units of volume/time) into a flow coefficient or Cv. This lets you directly compare the size of the valve to other vendors’ stuff.

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Mechanical

Replacing COTS gear stages with chain or belt

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Did you know you can use HTD pulleys instead of gears in the VexProSingle Reduction Clamping Gearbox, or in the 3rd stage of a Ball Shifter?

Here’s a spreadsheet of belt/pulley and chain/sprocket combinations that may be swapped into some common COTS 20DP gear spacings: 84, 90, and 112 teeth.

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Instructional videos

Triple Helix tech tips

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Triple Helix Tech Tips are an idea we’ve been mulling for a while. This is where we share our tips and tricks, which we hope will be useful especially for rookie teams. We’ve been around a while, and have learned some lessons, sometimes the hard way. Hopefully these will save you a little pain, a little time, and a little cash.

Video series

Instructional videos

2363 builds a drivetrain

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When we recruit new students, one of our favorite lines is, “Nobody who joins the team knows how to build a robot. We’ll teach you.” As an established team, we go to competitions and see younger teams, some of whom don’t have engineering mentors, struggling to learn lessons we have learned the hard way. We see our role in growing FRC as helping those struggling teams become better more quickly, so they remain inspired, and don’t fold.

Last fall our students came up with the idea of producing a series of instructional videos. These would teach our incoming rookies the skills they would need to be productive robot builders. We see this video series, and the ones which will follow, as a tool which can help educate inexperienced students on our own team as well as other teams across FRC.

Video series

Chief Delphi post

Mechanical

Fundamental resource archive

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Compiled by mentor Nate Laverdure in fall 2016, this document lists the top resources that have been helpful in his growth as an engineer and a mentor.  They are representative of his interests and opinions, and therefore lean towards mechanical systems and fabrication techniques.

Taken together, they constitute his idea of an archive of fundamental resources (papers, presentations, videos, websites, etc) which are essential to being “good at robots” in modern FRC. The idea isn’t quite right– in truth, every team has the capability for designing and fielding excellent winning robots regardless of how well-developed their library of knowledge is. However, compiling these resources gives new FRC designers a significant leg up by rapidly exposing them from lessons learned from hundreds of people, some of them with over two decades of experience in this competitive robotics program.

The biggest thing to learn from these resources is simple: that nothing in FRC is so complex or far advanced that it can’t be understood by anyone willing to put in the time to understand it.

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