Tube Versus Channel

[cadandcookies]

As a relatively new member to the FRC community (this is my second year in the competition) I have been very closely looking at other teams' robots, as seeing how different teams design is rather interesting to me. While doing this, both online and at regional competitions, I have noticed several things about frames, which have gotten me thinking about robot design in the future, as my team is likely to design some sort of showbot over the summer for outreach, as well as participating in future FRC seasons.

The main thing that I have been wondering about is structural materials. Namely, I've noticed several distinct types:

a) Channel

b) Tube

c) 80/20 or other extrusions

Noticing these differences lead me to wonder:

Why do teams choose these different materials?

I have several theories on the benefits of each.

For channel, it may be for convenience, as, if I remember correctly, 1" channel is the typical kitbot construction. Additionally, this isn't an all together structurally unsound material. This also may be perceived as cutting weight. It also only requires one hole to be drilled through the material to bolt something to it.

For tube, some possible reasons may be that it is more structurally robust than channel. Also, there is more area to mount onto, which may be a benefit.

For 80/20, possible reasons may be the ease of prototyping with this material, as well as the excellent structural integrity it affords.

I am interested as to why different teams choose these building materials, as well as what benefits and disadvantages are seen in them. If any other team members could offer some advice to this humble sophomore, I would be much appreciative.

If anyone has already posted a thread to this effect (I didn't see one when I searched, but I may have missed it), I would also be perfectly grateful with a link to that thread.

Also, this is specifically for metal robots. I am aware that some teams make wooden or plastic robots, but as these are rather uncommon, I would appreciate it if any discussion focused on materials for metal robots.