Moving a mass for ten seconds

[cypressfalls Robert]

Pitsco
Polulu Robotics & Electronics - Tamiya Motors and Gearboxes
Servo City - Tamiya Gearboxes
Tower Hobies - Tamiya Planetary Gearbox Set

which one of those is speed reduction? I only see speed increasing gearboxes.

[longliveemomusic]

Hmm, is everyone here attempting the string and motor method of moving the mass?

I'm using a rly long piece of threaded metal rod and a slow motor to move a block of wood along the threads of the rod.
This method is okay right?

[Flavorflav]

Pitsco
Polulu Robotics & Electronics - Tamiya Motors and Gearboxes
Servo City - Tamiya Gearboxes
Tower Hobies - Tamiya Planetary Gearbox Set

which one of those is speed reduction? I only see speed increasing gearboxes.

Look again.

Hmm, is everyone here attempting the string and motor method of moving the mass?

I'm using a rly long piece of threaded metal rod and a slow motor to move a block of wood along the threads of the rod.
This method is okay right?

Absolutely. People use string because it is easier to set up, but your method is more reliable (no tangles).

[fleet130]

which one of those is speed reduction? I only see speed increasing gearboxes.

I think you must be looking at the ratios backwards, they are all speed reducing.

[Gooblah]

Can this task be combined with the golf ball movement?

This is my first year doing this event in Division C (I did it in Division B, but that's a whole different ballgame). I was thinking having a motor/string method pull the golf ball slowly up 30 cm.

To be honest, it seems like a lot of these tasks can be combined in order to simplify the machine's design and construction....

[Balsa Man]

Can this task be combined with the golf ball movement?

To be honest, it seems like a lot of these tasks can be combined in order to simplify the machine's design and construction....

Nope- re-read the rules- no parallel paths, i.e., two tasks happening together. Each task is defined, then "...leading to the next..." Each one has to follow, and be initiated by the previous.

[Gooblah]

Can this task be combined with the golf ball movement?

To be honest, it seems like a lot of these tasks can be combined in order to simplify the machine's design and construction....

Nope- re-read the rules- no parallel paths, i.e., two tasks happening together. Each task is defined, then "...leading to the next..." Each one has to follow, and be initiated by the previous.

Still a bit confused...I don't have the rules in front of me ATM but I do have the .pps uploaded onto the soinc website...

What I meant was that the mass that is moved for 10-40 seconds could be the golf ball, since the golf ball's vertical movement does not need to trigger the 'next step', while the mass movement does.

The way I understood parallel paths was that two physically separate tasks couldn't happen at the same time; since these two tasks aren't physically separate, I didn't initially consider them parallel. Ugh, this means I'll need to redo my design...

[Dark Sabre]

We are kind operating on hearsay on this, since the question never made it to any of the official SOINC pages, but Paradox21 sent in the question:

Are you allowed to have one task complete 2 or more of the tasks listed to get points? For example, could you combine task c, turn a shaft for 40 seconds, with task g, raise a golfball at least 30cm, into one task that raises a golfball at least 30cm in 40 seconds and still get the points for both?

And they apparently said

It is not allowed because parallel tasks are not allowed.

(excerpt from here.)


So they seem to have taken the stand that the tasks are being completed in parallel, even though they are in a single action. Historically, the other interpretation has been followed, but I guess this year is different.

[Gooblah]

We are kind operating on hearsay on this, since the question never made it to any of the official SOINC pages, but Paradox21 sent in the question:

Are you allowed to have one task complete 2 or more of the tasks listed to get points? For example, could you combine task c, turn a shaft for 40 seconds, with task g, raise a golfball at least 30cm, into one task that raises a golfball at least 30cm in 40 seconds and still get the points for both?

And they apparently said

It is not allowed because parallel tasks are not allowed.

(excerpt from here.)


So they seem to have taken the stand that the tasks are being completed in parallel, even though they are in a single action. Historically, the other interpretation has been followed, but I guess this year is different.

Oh good lord...

Alright. My team is in kind of jam because our event spread was pretty bad this year, in the sense that certain events such as Mission Possible and Env. Chemistry have one or two people doing them out of the 40 people who are on the team. And for Mission Possible, none of the people technically signed up to do it have made any progress whatsoever, and the odds of them getting on the regionals team are kind of...low...so the Captains (incl. me) have been forced to pick up the slack and take on events that we normally don't do.

As a result, I spent about 30 mins poring over the limited resources about Mission Possible I had on me at the time (we're on break, so no access to event sheets for now) and came up with a plan that would minimize building time by combining as many tasks as possible. I think a few are still valid (for example, the mass carried for 10-40 seconds would block light to the photocell), but many are now rendered useless.

Well, time to get back to the drawing board!

[Balsa Man]

I think the key here is Rule 3c: "...designed and constructed to execute, consecutively, a sequence of tasks...
and roman iv. under that, "parallel task sequences are not allowed."

What DS is referring to, historically, I believe, is "parallel paths"- a subtle but important difference.

The interpretation from the FAQ is totally consistent because of this year's Rule 3c.

Clearer?

[aubrey048]

I used a lego motor w/ a shaft and a gear connected to an old bike tube that we shaved to make it flat. We used a slow motor, weak battery, and heavy mass (rubber fish ) to make it work.
We got it to turn for about 38 sec.

Sources: Me, MP gold medalist as of Saturday!

[11madmic]

we are using a threaded rod with a wing nut that when is reaches a certain point hits a pressure switch. it is powered by a motor with a belt on it it is easier to calibrate to 4o seconds.

[gh]

OK, so here's my take on the "string as mass" question: it's not any easier to use the string as the mass than if you put something heavier and the end, given that your "mass" still triggers the next step.

However, if your next step is triggered by say, pulling on something with a string, and you simply reel on slack string on a spool for 10 to 40 seconds until the string tugs on the next task's trigger, then I would consider that to not be a task completion.

Also, is anyone using a rotating moving mass instead of a translationally moving mass?

[mission52]

Is there any penalty for moving a mass longer than 40 seconds (say for example, 65 seconds) to reach the target time for the entire device?

[penclspinner]

Is there any penalty for moving a mass longer than 40 seconds (say for example, 65 seconds) to reach the target time for the entire device?

No penalty, the 40 seconds is just the max amount of time that will be counted toward the task points. You can keep your mass running for 60 seconds but you will only get 30 points from the moving mass task.