Robot Arm C

[starpug]

But time wouldn't be stopped if the magnet started in the robot's gripper as opposed to on the Arm Square, right?

There is a FAQ about this now: http://soinc.org/node/955

The bottom line is if anything comes detached from the robot, time stops, regardless of whether it was originally attached or picked up.

Oh, alright. So this would overrule any state clarification about the issue?

The clarification on soinc is official, what chalker just said is not.

[chalker]

Oh, alright. So this would overrule any state clarification about the issue?

The clarification on soinc is official, what chalker just said is not.

Quite true... as always, this is not the place for official clarifications. That said, I can assure you that what I said is the spirit of the FAQ I quoted. If in doubt, go ahead and submit a question on soinc.org.

Regarding state clarfications, different states handle it different ways. Some say they overrule national clarifications, in other states they don't.

[starpug]

Since we're all chiming in on this...

Our team does not have a lot of money, however we have decided to spend a sizable chunk of money on this event (over $200). In order to really understand why we did this you need to understand one thing, I don't know anything about this stuff, my partners knows less, and my coach knows nothing about it either. In fact, no one that I know of in my school has anything beyond a basic knowledge of this stuff. I have had to teach myself as I go along, with the help of some of the wonderful people on here. I took me a while to even buy things because I had no clue what components would even fit together. I believe the bulk of our cost came in the form of motors. Why did we buy a 128 oz-in stepper motor the size of my fist? Because when I ran my torque calculations, the number I came up with was quite large, larger than the torque or our big stepper motor in fact. I didn't really have the time to design an arm that would require less torque because I knew I had to get the components as soon as possible because I knew it was going to take me a while to even get them all together. I can't program, I can't solder, and I have very little clue about putting circuits together. I'm lucky that the technical documentation for my motor drivers tell me how to wire everything together because otherwise I would be in even more trouble. I'm sure you could build a robot for dirt cheap. Not having any expertise in electronics multiplies the time it takes to build the device many times. Since there is literally no one who can assist me with the electronic component of this event, I have to take the easier (and therefore more expensive) route or be in danger of not having the device ready in time for states. As it is I'm already not sure that the arm will be read in time. I think it's incorrect to assume that everyone either has the expertise or has the time to gain it. I guess I could have tried to go with something that was much easier to pull off such as pushing the items, but that still would have required lots of time and effort in order to pull off. Perhaps more importantly, it's not as easy as simply "well, I don't know what I'm doing so I'm going to take the easy route that will get me points but probably not medal." I am a competitive person, if possible I would much rather spend 200 dollars for a chance to medal and know that I did my best than 50 for points and the thought that I copped out. Also, don't forget that there is a chance that those points I lost by going the cheaper route could very well drop my team in the final results, or even keep us from going to nationals.

One last thing about this event makes it difficult. It is different from a gravity vehicle or a towers or a sounds of music in that not only if you break something is it probably going to be expensive, but you will probably have to reorder that part to be shipped to you and there is a certain level of danger in it. Allow me to tell a brief anecdote. Today we put wheels onto our gravity vehicle so we could test it. The wheels were CDs and knowing that 2.5kg going down a ramp and hitting the floor at a rather sharp angle (we haven't flattened it out just yet) my partner and I figured that the CDs would probably break when the car came off the ramp. We attempted to test the car anyway, and we were exactly right. The back two wheels literally exploded and the front wheels cracked and unglued themselves from their washers.

I would never do something with my robot arm knowing it would fail. I don't want to have to wait a week for the new components to arrive and I don't want anything to explode. Yes with expertise you learn how things work and the odds of disaster are lessened, but I'm far far from an expert. Therefore I have to take my time and I have to double and triple check my wiring and I have to send pictures of wiring to people who I've met online to reassure me that I haven't done anything horrendously wrong.

So what did I just say? I honestly don't know. I just hope I said what I was trying to say.

[jander14indoor]

Let me give one state policy. Here in MI, if a FAQ or Clarification is posted on the national site 30 days before the STATE tournament, we consider it binding on the STATE event supervisor. Posted in those 30 days advisory. After the tournament, not relevant. We sometimes issue MI state only clarifications if no national ruling, or local circumstances prevent/dictate something. Example, MI state law has more stringent safety requirements for work in the labs at a university. They dictate, not the SO rules.

The following is a quote from the NSO clarification page (emphasis mine):
Rules Clarifications
Official Rules Clarifications are made to clarify or correct the rules printed in the manuals. FAQs are replies to commonly asked questions. These Official Rules Clarifications and FAQs apply to all states and all tournaments and originate at the national level (please check your state web sites for special updates pertaining to your regional or state events).

In general, the states and regions are allowed by NSO to deviate from NSO rules if needed by circumstances like our lab rules, but they must be posted and available to the students.

Note, this is not a statement about MI region policies on clarifications. Those vary.

Jeff Anderson
Livonia, MI

[rnphoenix42]

I just thought I'd throw in my two cents on the whole cost issue:
I'm wouldn't say that I'm an EXPERT in robotics, but I have been part of FIRST for about 7 years now, so I know the basics about robotics and electronics, and I can solder fairly well. Our robot was mainly built from parts from Lynxmotion, but this was only because we were running short on time and all the lynxmotion parts sort of "fit" together (like a kit, but not really) and I didn't know where else i could get aluminum tubing (but I could have just as easily used PVC if I really wanted to). Our biggest cost went into buying decent servos (our most expensive servo, in the shoulder, was around $30) which could be able to pick up the D batteries. If the D batteries were not part of the competition, we could have easily made do with much lower torque servos. I programmed the whole thing with an arduino, which really isn't much more expensive than any radio receiver, and our controls were tethered so we didn't have to worry about buying a receiver. Altogether, our whole robot came up around $200. Yesterday, at our regional, I saw several robots made out of LynxMotion parts as well (at least the grippers and servo brackets) and a few also made from VEX, and of course there were also a few OWI robots there (I really do not like the OWI kits).

What I'm trying to get at however, is that we essentially built a robot "from scratch" like many other people before have been talking about. The thing is, even if you build a robot from scratch, if you want it to be competitive and be able to do well at state or nationals, you're still going to have to fork out the cash for strong motors that are also fast. Also, unless you are very good with putting together structures (which I admittedly am not), getting a kit is the best way to go for many teams. A few students on our team built another robot which was made from VEX, and I would have built my whole structure out of VEX as well if they hadn't used up all the parts before i got to them The hardest part for me was figuring out a way to make a structure completely from scratch, and by that i mean just finding scrap parts etc and putting it together, while at the same time keeping the robot sturdy and secure. I feel like, along with the lack of expertise issue many teams have, this is another reason why they often fall back on the kits, because its just much more convenient for them. Now, i'm not saying that you can't build a $50 robot and do well at the competition with cheap motors, a scrap-metal frame, and a really good design, I'm just saying that it would be a lot harder to put together and make solid than someone who built their whole thing out of VEX parts or any other kit for that matter.

[illusionist]

Different topic, shouldn't there only be one bonus jug on the competition area? The regionals in this video had two- http://www.youtube.com/watch?v=neHuC63n ... re=related . (I think he wins most creative use of 3:00)

[jander14indoor]

woot, no opinion this time, just a quote from the rules:
para 5.f "One unmodified half-gallon jug with the cap removed (the “Bonus Box”) is placed at one of the two North corners of the Competition Area by the Event Supervisor..."

Wait, maybe there is an opinion involved. What is the definition of "one" afterall...

[illusionist]

This clarification states- "If items are placed in the goal box by use of a tool,such as a magnet,and that tool is left in the goal box, can you still receive full points for those items?
If the magnet is detached from the arm before the scoreable item is in the goal box, the item will not receive points because time is stopped when the magnet is detached from the arm."

This scenario is easy to understand if the arm drops the magnet from one or two inches above the goal box. Suppose the arm with magnet still attached places the nails inside a goal box, so that they touch the base of the goal box, then releases the magnet while still inside the goal box. The items aren't supported fully by the goal box until the instant that the magnet is released. Timing will still stop once the magnet is released. Unofficially, would these objects receive full points? I would assume no, but just want further opinion.

[JBoyd-NY]

OK, I'm confused. Hopefully, someone can offer me an explanation that clarifies things for me.

There is a FAQ that states that if any part of the robot becomes detached from the rest of the robot, time will be called. I believe that this FAQ is based on rule 6.c.vii, which states that time will stop when "The Arm(s) become detached from the optional Base". I'm making that assumption because 6.c lists 7 reasons for calling Time, and the only one that refers to parts of the arm becoming detached is 6.c.vii.

Here's the hypothetical scenario that has me confused:

I build a robot arm that does not use an optional base. At the start of the competition, I use a permanent magnet that is held by the claw at the end of the arm to pick up 4 nails. I raise the arm after securing the 4th nail and move the claw so it is over the North goal box. I then open the claw, releasing the magnet and the 4 nails into the North goal box. The event supervisor calls Time and informs me that I receive no points for the nails, and the only points I get are the 12 points for all three Goal Boxes remaining upright. I ask the event supervisor which rule he is enforcing when he calls Time and he states that he is enforcing 6.c.vii. When I point out that I have no Base, that the Base is optional and is therefore not required, and that 6.c.vii cannot apply to my robot arm since my arm cannot possibly become detached from a part of the device that does not exist, and that 6.c.vii applies only to robot arms with optional Bases, he then tells me he is going by the FAQ that says time stops when any part of the arm becomes detached from the rest of the arm.

I was under the impression that FAQs answered questions about the rules, but they could not, in fact, become additional rules. It appears to me that this particular FAQ is an additional rule, added to those included in the official Rules Manual, since it implies that robot arms that do not have optional Bases cannot detach parts when there is no rule in the rule book that speaks about parts of the arm becoming detached except for 6.c.vii, and that rule only applies to robots with optional Bases, much like rule 3f only applies to arms that are controlled via radio frequency. If 6.c.vii was meant to apply to arms with and without optional Bases, then why mention the Base at all? Why not simply state that time will be called when "any part of the robot arm(s) become detached from the rest of the robot arm"?

[eta150]

OK, I'm confused. Hopefully, someone can offer me an explanation that clarifies things for me.

There is a FAQ that states that if any part of the robot becomes detached from the rest of the robot, time will be called. I believe that this FAQ is based on rule 6.c.vii, which states that time will stop when "The Arm(s) become detached from the optional Base". I'm making that assumption because 6.c lists 7 reasons for calling Time, and the only one that refers to parts of the arm becoming detached is 6.c.vii.

Here's the hypothetical scenario that has me confused:

I build a robot arm that does not use an optional base. At the start of the competition, I use a permanent magnet that is held by the claw at the end of the arm to pick up 4 nails. I raise the arm after securing the 4th nail and move the claw so it is over the North goal box. I then open the claw, releasing the magnet and the 4 nails into the North goal box. The event supervisor calls Time and informs me that I receive no points for the nails, and the only points I get are the 12 points for all three Goal Boxes remaining upright. I ask the event supervisor which rule he is enforcing when he calls Time and he states that he is enforcing 6.c.vii. When I point out that I have no Base, that the Base is optional and is therefore not required, and that 6.c.vii cannot apply to my robot arm since my arm cannot possibly become detached from a part of the device that does not exist, and that 6.c.vii applies only to robot arms with optional Bases, he then tells me he is going by the FAQ that says time stops when any part of the arm becomes detached from the rest of the arm.

I was under the impression that FAQs answered questions about the rules, but they could not, in fact, become additional rules. It appears to me that this particular FAQ is an additional rule, added to those included in the official Rules Manual, since it implies that robot arms that do not have optional Bases cannot detach parts when there is no rule in the rule book that speaks about parts of the arm becoming detached except for 6.c.vii, and that rule only applies to robots with optional Bases, much like rule 3f only applies to arms that are controlled via radio frequency. If 6.c.vii was meant to apply to arms with and without optional Bases, then why mention the Base at all? Why not simply state that time will be called when "any part of the robot arm(s) become detached from the rest of the robot arm"?

FAQs can't be used as rules clarifications, but they can be used for informational purposes ahead of time.

Also, on the official soinc website, the FAQ mentions nothing about the base.

03/02/2012 - 15:36 Are there any penalties if any part of your device falls off into the competition area or becomes detached from the device during competition.

There are no penalties but timing stops when any part of the arm falls off or becomes detached from the arm.