Hydraulics?

Originally Posted by s_forbes

Fortunately we don't build such complicated systems for the FRC... although if a team showed up with something like that they would become an instant favorite of mine!

I think it's interesting that teams are allowed to compete with some dangerous and failure-prone electromechanical mechanisms year after year, but for some reason the thought of a hydraulically actuated device is thrown right out the window for safety reasons. I understand the oil-on-field issue, but if we're using something that's field-safe like water, is there actually a serious risk? (reference some 2008 catapult robots when making your comparison. )

I love how we are limited to certain parts and mechanisms due to "safety", yet half of the games wield robots who can majorly harm people and objects. Two examples are from 2008 and 2010. Some robots in 2008 could shoot the track ball so high and far at such high speeds, if one shot out of the field it would damage something, or severely injure someone if they get hit. Same with 2010. Some robots in there could fire soccer balls off so hard that it could be serious injury to anyone, and could be life or death if it hit someone in the head (Maybe a little exaggeration.....).

[davepowers]

Originally Posted by SuperNerd256

I love how we are limited to certain parts and mechanisms due to "safety", yet half of the wield robots who can majorly harm people and objects. Two examples are from 2008 and 2010. Some robots in 2008 could shoot the track ball so high and far at such high speeds, if one shot out of the field it would damage something, or severely injure someone if they get hit. Same with 2010. Some robots in there could fire soccer balls off so hard that it could be serious injury to anyone, and could be life or death if it hit someone in the head (Maybe a little exaggeration.....).

So you're refering to something like this happening? Poor Dean, why'd it have to happen to him? .

-Dave

[Tristan Lall]

Originally Posted by SuperNerd256

I love how we are limited to certain parts and mechanisms due to "safety", yet half of the games wield robots who can majorly harm people and objects. Two examples are from 2008 and 2010. Some robots in 2008 could shoot the track ball so high and far at such high speeds, if one shot out of the field it would damage something, or severely injure someone if they get hit. Same with 2010. Some robots in there could fire soccer balls off so hard that it could be serious injury to anyone, and could be life or death if it hit someone in the head (Maybe a little exaggeration.....).

There's a bit of interesting backstory behind the safety-related restrictions over the years. Basically, FIRST has had different concepts of what is adequately safe from year to year. As safety enforcement is generally implemented by interpretation of the catch-all safety rule (typically <R01> or <S01>), there is great discretion given to officials. While there are efforts among the referees and inspectors to standardize their rulings within a year, and FIRST gives this thought between years, the outcomes of this process aren't always adequately communicated to the teams.

In 2006, in particular, FIRST pushed hard for safety, both in terms of ball speed (they tested it against a limit) and in terms of mechanism design. They instructed the inspectors to require significant shielding of rotating machinery on shooting mechanisms. This standard was a bit more restrictive than teams had been used to, and there were a few teams, 188 included, that got tripped up by it. There may have been a Q&A response about it, but perhaps the most prominent documentation of such a standard was the (official but non-binding) inspection checklist, which read "Safety and Wedges: No sharp protrusions or edges, no entanglement risks, no wedge-shaped robot bases that may potentially affect other robots, shooter mechanisms (if used) must be shielded (3/4” dowel test)". This was also discussed at length among inspectors, and the directive was to draw upon industrial practices for guarding of machinery.

So, returning to your original point, this was an attempt to avoid the possibility of serious injury (pinch points in shooters), and yet it was unhappily received by the teams, who were too disappointed at the onerous interpretation to care that FIRST was trying something new to promote more safety across the board. I don't hold this up as an example of great policy—after all, there are very few opportunities for a person to make contact with a robot (protrusions excepted) during a match—but I do think that FIRST probably deserves credit for trying to be safety-conscious when it comes to mechanism design.

And incidentally, let me reiterate that the hydraulic ban is not mainly a safety concern—it's a cleanup concern. It's the pneumatics rules that are primarily safety-driven—and they're conservative to a fault.