Robot Arm C

[jander14indoor]

Not sure I want to know which one it was, there were a number of well performing robots at Wright State's invitational, some with really clever ideas in the process of being worked out.
I can say good luck at regionals as I'm not running Robot at any of those this year, Wright Stuff and Helicopters till states.

Jeff Anderson
Livonia, MI

[windu34]

Jeff I was hoping you could provide some unofficial insight into how supervisors determine whether or not a penny is "in" a circle or not - especially the ones that are very borderline. Do you have a specific system or method?

[maxxxxx]

I am just wondering what would a competitive score at the state level be?

I'm guessing medals in competitive states will be a score of 400+, with most 1st places somewhere around 550-600.

I somehow added up the maximum score at States to be 618, but it's actually 782. I would now expect medals to be 500-550+ and 1st place to be 700+ in most states.

[Bazinga+]

Jeff I was hoping you could provide some unofficial insight into how supervisors determine whether or not a penny is "in" a circle or not - especially the ones that are very borderline. Do you have a specific system or method?

I would also like some clarification on this. As you know the maximum number of pennies that can fit in the innermost circle is 12, but that is a very tight fit (pennies a fraction of a mm within). How would an event supervisor determine whether a penny is within a certain circle if it comes down the the fraction of a mm, something the human eye can't really differentiate.

[Chameleon02]

The rules say that the arm may not extend higher than 100cm in ready to run position. So is it allowed for arms to be taller than 100cm if fully extended in the middle of the run, or are they not allowed to extend past 100cm vertically at any part of the run? Our arm has one joint, and if folded, it can be about 70cm tall. So before the run, it can fit the 25x25x100 imaginary box. But if we stretch it vertically, it well exceeds 100cm. We have a competition this week, and I dont know if I have time for an FAQ.

[bernard]

The rules say that the arm may not extend higher than 100cm in ready to run position. So is it allowed for arms to be taller than 100cm if fully extended in the middle of the run, or are they not allowed to extend past 100cm vertically at any part of the run? Our arm has one joint, and if folded, it can be about 70cm tall. So before the run, it can fit the 25x25x100 imaginary box. But if we stretch it vertically, it well exceeds 100cm. We have a competition this week, and I dont know if I have time for an FAQ.

Ready-to-run refers to the configuration of your device the instant before each run. As long as your device fits in the 25 cm x 25 cm x 100 cm imaginary box at that instant, it satisfies the rule. The wording does not require it to fit in such an imaginary box throughout the duration of each run.

[jander14indoor]

Jeff I was hoping you could provide some unofficial insight into how supervisors determine whether or not a penny is "in" a circle or not - especially the ones that are very borderline. Do you have a specific system or method?

UNOFFICIAL insight only! And "sight" is a key issue here.

Rule 7.a states: "Any pennies in multiple zones and/or touching the line separating two zones as determined by the ES..."

This will depend on the eyesight and judgement of the ES. This is not a tolerance or distance issue. If it is visually touching the line, it gets the lesser score. No measurement, no tolerance.

Now, before you get too worried, the human eye CAN see fractions of a millimeter without problem. For example, even with my old eyes, with my glasses I have no problem seeing the layers on objects from my 3-d printer even when printing layers as small as 100 microns. Yes, I now need my reading glasses, but I can see them, and that is on a monocolor surface. Yes lighting plays a part, but I can see them. On something like touching or not, I can probably see even smaller because of contrast. You are looking for a thin line of the base color between the penny and the contrasting black line. If you can see it you should get the score for being in the ring, if not, you are touching and you get the lesser score.

As a reference, one source I looked up said a good eye can resolve details as small as 26 Microns, practical is closer to 40 microns. Without magnification.

I did some additional figuring, the smallest circle that fits 12 pennies is 7.915 cm. So there is 0.85mm of 'extra' space. The visual error is on the order of .04 mm or 1/20th of the available space. So the visual error here doesn't eat much of the admittedly SMALL tolerance for coin placement.

<SNIP>So is it allowed for arms to be taller than 100cm if fully extended in the middle of the run, or are they not allowed to extend past 100cm vertically at any part of the run? <SNIP>

Already answered, but here is another way to think of it. The rule is 25X25X100 with no distinction between those measurements. If you couldn't violate the 100 cm dimension during the run, wouldn't that logic apply to the 25 cm dimensions? And in that case how could you ever score anything?
Said another way, if the robot can extend beyond the 25X25 cm dimension, why can't it extend beyond the 100 cm dimension?

Jeff Anderson
Livonia, MI

[laidlawe18]

This is a little nitpicky, but are the lines between rings completely within the lowering scoring of the two zones? In other words, is the diameter of the white (or whatever base color) circle in the middle going to 8 cm, or 8 minus the thickness of the line cm. If the line is even half a millimeter thick, this could be a huge difference in tolerances.

[bernard]

This is a little nitpicky, but are the lines between rings completely within the lowering scoring of the two zones? In other words, is the diameter of the white (or whatever base color) circle in the middle going to 8 cm, or 8 minus the thickness of the line cm. If the line is even half a millimeter thick, this could be a huge difference in tolerances.

Ask the supervisor how lines are counted. At regionals, we used a hand drawn archery target with very thick lines. Before each run, I made sure teams understood that I was counting pennies on the line as the higher scoring ring but pennies past the line as the lower scoring ring. For state, I will use a target with no lines.

[AlbatrossTree]

In Ohio there seems to be a few scores breaking 400 (based on invitational scoring). Has anyone been scoring that high?