Robot Parts and Materials - Answer Thread

[Administrator]

Answers to your questions about Robot Parts and Materials.

[Sheldon]

Are the following items (from Home Depot and Lowe's) considered legal Commercial Off The Shelf (COTS) assemblies as defined by R02.a.1 (Game Manual Part 1, Rev 4, Page 18, Linear Slides)?

Lowe's Item #: 89226
http://www.lowes.com/pd_89226-89973-...ide&facetInfo=

Home Depot Store SKU # 404370
http://www.homedepot.com/h_d1/N-5yc1...1#.UFw5zpiuKo4

Lowe's Item #: 89226
http://www.lowes.com/ProductDisplay?...llow&cId=PDIO1

A: Yes, all three are legal COTS per Rule <R02.a.1>

[Sheldon]

We propose to design some plastic parts and have them 3D printed. We actually want to print them ourselves, but our design of the parts has come together before we have a working 3D printer - like a RepRap or Makerbot or hybrid. We intend to have finish our build of a 3D printer before we have any competitions, but we would really like clarification on the whole built part issue. So if we were to print our own part, we think we would be well within the rules, but what if we design a part and have it printed by someone else? Please clarify.

A: 3D printed parts are not considered to be pre-fabricated or pre-formed COTS and are legal per rule <R02.b.1>

[Sheldon]

Are "ball bearing drawer slides", available at Home Depot and Lowes, considered to be "linear slides"?

A: Yes, "Ball Bearing Drawer Slides" are legal COTS assemblies per Rule <R02.a.1>

[Sheldon]

Section <R02> b. 1. establishes that extruded aluminum is not considered a prefabricated part and thus falls into the raw material category. <R02> d. allows the use of raw materials provided that they are readily available from standard distributors such as Grianger or McMaster-Carr. My conclusion from this is that T-slot extruded aluminum extrusions such as those supplied by 80/20 and which are available from Grainger and McMaster-Carr, are allowable materials. Is this a correct conclusion? If it is, what are the limits on associated components which work with such materials such as fasteners?

A: Yes, aluminum extrusions from 80-20, Macron, Parker, McMaster-Carr, etc. are legal per rule <R02.b.1>. The fasteners associated with this extrusion, such as T-nuts and T-bolts are also legal per rule <R02.d.3> .

>>>>>Updated<<<<<<< The GDC has determined that prefabricated components such as corner brackets, joining plates, linear slides, etc. that are compatible with the extrusion are legal per rule <R02.a.1>.

[Sheldon]

Is 3D printing allowed this year (using eg 1/8" ABS as a base material)?

A: Yes, 3D printing is allowed.

[Sheldon]

Could a team design a method to pick up another robot with the use of a universal attachment that could be put on their alliance partner's robot prior to a match? Would that be legal?

A: There is no rule prohibiting the use of a Universal Attachment. However this attachment must be fabricated from allowable materials and the robot with attachment must comply with all applicable robot rules.

[Sheldon]

it would sure be nice to allow some sort of pulleys and cog belts. I presume that they are excluded given <R02> "Prefabricated and/or Preformed COTS plastics or metal are not permitted..." but this rule could REALLY limit what we use for pulleys...eg, sewing machine bobbins - illegal, thread spools - illegal...right? so the only pulleys we can use are ones we make?

A: Pulleys and cogs, including bobbins & thread spools, are considered COTS parts and are not legal per rules <R01> and <R02>.

[Sheldon]

Is PVC piping and couplers, of any size, considered as raw material or a preformed parts?

A: Yes, PVC pipe and fittings are considered a raw material and are allowed per rule <R02.b)

[Sheldon]

In reviewing <R02> d. It lists raw material, fasteners, standard bearings and bushings. Would typical helical/coil springs be allowed or are those considered an assembly?

A: Springs are considered a preformed COTS and are not allowed per rule <R02.b)