pic: REV Robotics building system

[Greg Needel]

loading photo ...

[mman1506]

Is the linear motion system supported by ball bearings or bushings?

[Greg Needel]

Originally Posted by mman1506

Is the linear motion system supported by ball bearings or bushings?

The linear motion system uses v-groove ball bearings.

[orangemoore]

Do you have any idea when "very soon" is?

This looks cool.

[mman1506]

Originally Posted by Greg Needel

The linear motion system uses v-groove ball bearings.

Awesome! (image seems to be broken BTW)

[cgmv123]

This looks suspiciously similar to a certain Industrial Erector Set.

[tim-tim]

Originally Posted by cgmv123

This looks suspiciously similar to a certain Industrial Erector Set.

...but way more suited for the FIRST community.

Greg, any way to get strengths/specs? I am really looking forward to the products REV Robotics are releasing.

[Mike Marandola]

I love the fact that you can use standard hardware with this. I might be missing something obvious, but what are the grooves in the corners meant for.

[Richard Wallace]

Originally Posted by Mike Marandola

I love the fact that you can use standard hardware with this. I might be missing something obvious, but what are the grooves in the corners meant for.

Looks like you could tap them.

[mman1506]

Originally Posted by Mike Marandola

I love the fact that you can use standard hardware with this. I might be missing something obvious, but what are the grooves in the corners meant for.

According to their FB

All 5 holes on the end of each profile are designed to be tapped the same thread pitch as the hardware used in the slot. 10-32 for the 1" and M3 for the 15mm profile.

One of the reasons for the extra end tap holes is so your cross members wont have the ability rotate when you use the extrusion as a spanner between 2 plates.

[Mike Marandola]

Originally Posted by mman1506

According to their FB

That makes sense. I was just confuse by the openings. I guess it just makes it easier to manufacture.

[Greg Needel]

Originally Posted by cgmv123

This looks suspiciously similar to a certain Industrial Erector Set.

I have used 80/20, Bosch, ITEM, Microrax, and probably a few others over the years and I have loved them and hated them at the same time. They made building and prototyping really easy, but all of them follow the Razer + Blades business model of selling the profile for a reasonable price, but all of the hardware and accessories are expensive. Since you are already in their system you are stuck. This problem is one of the 2 major driving factors in the design of our system.

1) standard hardware decreases the cost of every attachment point from $.40 per nut (.20 if you are lucky) down to .02 by using standard hardware. This gives you the build experience that is so awesome at a much more cost effective price for schools and teams.

2) Linear motion is normally hard or expensive. Over the past 13 seasons I have been involved in FIRST there have been many amazing products which have changed the game (things like the shifting transmission, systems of gearboxes, sprockets, and wheels that just work together). The one thing that has remained hard for teams is linear motion. There are low cost options like drawer slides and more pricey solutions like ground rods and linear bearings but up to this point nothing that was designed with building a robotics elevator in mind. The V groove bearings and integrated features in the 1 inch profile allow for super easy integration anywhere in your mechanism.

Originally Posted by Mike Marandola

I love the fact that you can use standard hardware with this. I might be missing something obvious, but what are the grooves in the corners meant for.

Oh I forgot to mention this on Facebook, but you can also use a NYLOCK nut in our channel for added security.

As for the corners there are a few reasons (some more obvious than others).

When you design a part to be aluminum extruded it is in your best interest to keep a constant wall thickness through your part, this helps with the flow of the aluminum (similar things come into play when designing plastic parts also). Secondly the amount of closed profiles in your extrusion makes the dies more expensive and harder to get consistent results. Specifically speaking to the 15 mm profile it would have been almost impossible to do a closed hole in the corner.

As mentioned above all 5 of the holes can be tapped with allows for some interesting applications, one of which is mounting a hub to the end and driving it with a motor to turn our extrusions into a shaft that could be used for a pickup. Along that same lines the slot in the corner is specifically sized to accept a 1/6" piece of flat stock (lexan or other), I am sure you can probably think of a few times this would be useful

[BJC]

Originally Posted by Greg Needel

snip/

2) Linear motion is normally hard or expensive. Over the past 13 seasons I have been involved in FIRST there have been many amazing products which have changed the game (things like the shifting transmission, systems of gearboxes, sprockets, and wheels that just work together). The one thing that has remained hard for teams is linear motion. There are low cost options like drawer slides and more pricey solutions like ground rods and linear bearings but up to this point nothing that was designed with building a robotics elevator in mind. The V groove bearings and integrated features in the 1 inch profile allow for super easy integration anywhere in your mechanism.

/snip

It seems to me that the x shape and the very thin material that allow for the nut pockets on all four sides make this extrusion very susceptible to twisting loads. I noticed above you advocated using this for an elevator. Currently, many teams prefer 2x1 rectangular tubing for an FRC-type elevator because (among other reasons) its resistance to twisting is highly desirable to prevent binding. While it is probably serviceable in shorter/low loading situations, in a game such as 2011 Logomotion where elevators where the full 60" tall I don't think this extrusion would function very well in place of 2x1.

I do think that this is a really cool addition to teams' resources though. With the sliding nuts on each side it could especially have FRC applications in rapid prototyping.

Cheers, Bryan

[sanddrag]

Generally, with this type of profile available from other manufacturers, the purpose of the T-nut is to drop it in anywhere on the profile, and then it rotates into place before tightening. This allows for easy additions of brackets to the middle section of the beam, even if the end sections already have brackets and hardware installed.

How would this be accomplished with normal hexagonal nuts? Would you pre-load the profile with any and all hex nuts you ever intend on using, and let them float free until you do? Or would you need to disassemble bracketry on one end to add something more to the middle?

[JB987]

Originally Posted by sanddrag

Generally, with this type of profile available from other manufacturers, the purpose of the T-nut is to drop it in anywhere on the profile, and then it rotates into place before tightening. This allows for easy additions of brackets to the middle section of the beam, even if the end sections already have brackets and hardware installed.

How would this be accomplished with normal hexagonal nuts? Would you pre-load the profile with any and all hex nuts you ever intend on using, and let them float free until you do? Or would you need to disassemble bracketry on one end to add something more to the middle?

Or perhaps an actual drop in t-nut would also work on this extrusion?