[FTC]: Lift systems/Time?
 

It seems since this past weekend (after the new high scores) a lot of teams have said they are completely redesigning there robots, but I was wondering if teams redesign there robots and still keep the ball collection or any part of the robot, will they have have enough time to build it in such a way for the lift to work with the rest of the robot? I think teams will have enough time between now and Worlds (like the teams that have Invitations) but I don't know about having it ready by some State competitions, because there has been a lot of qualifiers and state competitions already, and most of them are with in the next month or so. Thanks and please tell me your thoughts.

Re: [FTC]: Lift systems/Time?
 

As a team that will NOT be redesigning their robot, we would like to warn teams about the amount of work that goes into creating a lift system. For us at least it took a LONG time to get the lift right. If you are redesigning power to you but I would NOT redesign if I had to make the decision right now.

Re: [FTC]: Lift systems/Time?
 

I completely agree with you, our lift took a very long time to make, we spent a lot of time on off practices to get it right because one practice a week is nothing close to enough. Not only do you need to build a lift, you need to flip a crate, put a ball in it, lift it, have something that holds it, then lift. Its a long process to get everything working together but I think it can be done if you spend enough time on it. I think most high lifting teams will want a partner that can flip crates, put balls in them and then bring them to the team with the lift, but that's just what I think will happen.

Re: [FTC]: Lift systems/Time?
 

I think now is a good time to bring up some other things about the lifts.

Do you think FIRST meant for this game to be based around lifting? It makes all other scoring methods mostly useless.

Second, what are your strategies for defending against lifting? How easy do you think it is to move crates around on the ground and make it difficult for teams to get? It seems to me simply nudging a crate can make a team take an extra 15 seconds. There are a few other great ways to prevent teams from holding a crate up at the end of the game that I haven't heard talk of, too.

But yeah, what are people's thoughts regarding this stuff?

Re: [FTC]: Lift systems/Time?
 

I've come up with a linear lift system that would be really easy to build and implement, however working out the kinks in a lift system is really what takes most of the time. I think the teams with scissor lifts did a great job and have proven scissors to be great mechanisms for this game (even though I don't like them really)

However for sake of argument I'm going to throw this in there. I am a strong believer that if a team were to implement it correctly a Linear system would A be faster to lift B be higher and C much much more efficient (all relies on design of course)

What does everyone think?

- Andrew

Re: [FTC]: Lift systems/Time?
 

What do you mean by a linear lift system? Can you be a little more specific?

Re: [FTC]: Lift systems/Time?
 

We are using a linear lift system!

In other words H3X, rather than using two sissors to lift up crates, it uses 1 telescoping rod.

Re: [FTC]: Lift systems/Time?
 

Not a scissor lift.

http://team254.com/wp-content/upload...254-2011-1.jpg

Best example. :D

- Andrew

Re: [FTC]: Lift systems/Time?
 

Re: [FTC]: Lift systems/Time?
 

Nothing more than truth in that post!

Just to poke the fire a bit more I figured out a way to get 19 feet with a linear lift, can anyone figure out how? ;)

- Andrew

Re: [FTC]: Lift systems/Time?
 

Our experience has been most of the 2nd year and older teams have implemented a lift system. There are a few rookie teams building them but most have their hands full learning all they need to know about FTC.

The lifts come in various flavors: Nested slides, roller and track, 4-bar linkage, single arm lifts, and scissor. The scissor lifts are the most common.

We've observed that most lifting robots are one trick ponies. Half of the are in barely working order and the rest are very slow, requiring a great deal of time to set and lift.

Re: [FTC]: Lift systems/Time?
 

For the most part that is true, this year our gear ratio is 1:1 because last year we did 2:1 and it was to slow and plus we pushed the middle of the field all the way to the other side in auto mode twice at Worlds. So at lest we aren't slow this year.

Re: [FTC]: Lift systems/Time?
 

@Aperture: Actually, yes. Just not sure how to store the helium. :)

Re: [FTC]: Lift systems/Time?
 

hehehe Helium storage wouldn't pass inspection silly...

Actually pnuematics would be pretty cool...

- Andrew

Re: [FTC]: Lift systems/Time?
 

I think you can use lego pneumatic's

Re: [FTC]: Lift systems/Time?
 

From our experience reading and doing research the past few years, the lego pneumatics are nowhere near powerful enough to do anything like this.

Re: [FTC]: Lift systems/Time?
 

Yeah... But... Those are kind of lame.

Re: [FTC]: Lift systems/Time?
 

Better then nothing. And you could use a ton of them and pump them up with a bike pump before every match.

Re: [FTC]: Lift systems/Time?
 

Hi teams.

For the record... G-FORCE only uses one motor for it's lift, and we've demonstrated a two-crate 86" lift in 4 seconds.

For anyone starting a new lift design, I recommend NOT trying for a hail-mary 10-section lift idea. The forces required to start the lift are magnified by each section you add, and rubber bands will only help if you want to launch the balls into the air. If you want to be successful, start with a few segments (eg: 4) and get that working, and then add some weights to see how much more it can lift. Then if you have power to spare, add segments.

As for defensive strategies... sure, you need them some times, but two purely defensive robots on an alliance will never score any points. I'd focus on teamwork strategies to help your partner score more.... maybe helping to collect crates with balls so they can lift them. Focus on at least one scoring method.

I was laso amazed to see how many rookie teams had not even tried to roll the bowling ball. You don't have to get it up into the goal to score 20, just roll it over to the ramp in end-game and sit there.

Re: [FTC]: Lift systems/Time?
 

Our previous robot design was completely powered by rubberbands and "held back" by a motor which would release it when necessary. We were able to reach the 8th level with 1 basket but chose to change our design because we were unable to bring our scissor lift back down with the power of the motor.

Re: [FTC]: Lift systems/Time?
 

I stand corrected... Using the motor to brake the lift's motion is a good way to deal with rubber bands, but it did move the power problem to the other end of the motion.

Of course it's OK to use human power to bring the lift down again, but you probably discovered that it's quite a bit of force to apply.

What does your "new" design do?

Re: [FTC]: Lift systems/Time?
 

It took QUITE a bit of force (one almost-adult, male team member using all the force he had to push down while running the motor backwards to spool up the rope)

I am not currently at the liberty to talk too much about our most recent design but it uses an ACME threaded rod for movement along with the aid of rubber bands. It does go both up and down, which is a step up, and is very quick to lift. :)

Re: [FTC]: Lift systems/Time?
 

Cool. Learning how to build a linear actuator is a great project.

Re: [FTC]: Lift systems/Time?
 

Even though we successfully created a stacking robot, we have decided to completely redesign our bot and strategy as stacking was just not getting enough points (even though we are using it at our regional competition next week at PACE University).

We have successfully created a linear lift. Currently, it goes up around 156", but we still have room to expand more!

Re: [FTC]: Lift systems/Time?
 

That will be fun to see.

Re: [FTC]: Lift systems/Time?
 

Well, in my mind there can't be any question that this is EXACTLY what first wanted...

Lets face it... if you stack the maximum of 6 crates you can only get 36" high. What does the rules manual show for point scoring?

a. 0 < H ≤ 10.5” (26.67cm) scores 0 points
b. 10.5” (26.67cm) < H ≤ 16.5” (41.9cm) scores 10 points
c. 16.5” (41.9cm) < H ≤ 22.5” (57.2cm) scores 20 points
d. 22.5” (57.2cm) < H ≤ 28.5” (72.4cm) scores 30 points
e. 28.5” (72.4cm) < H ≤ 34.5” (87.6cm) scores 40 points
f. 34.5” (87.6cm) < H ≤ 40.5” (102.9cm) scores 50 points
g. 40.5” (102.9cm) < H ≤ 46.5” (118.1cm) scores 60 points
h. An additional 10 points for every 6.0” (15.24cm) increment above 46.5” (118.1cm)

How else could you get above 46" without lifting....
If they didn't want us to lift they would have capped at some arbitrary level.

Re: [FTC]: Lift systems/Time?
 

I'm waiting to see a team stack ontop of one of those lifting robots.
Team 1102 has a linear actuator system on their robot. it can successfully stack and lift said stack without a problem. It's not a scissor lift but given a tall enough stack I think lifting 6 crates up 36 inches should get enough points.

Re: [FTC]: Lift systems/Time?
 

My team (4299 Battery Powered Picklejar Heads) has gone for a quite unique strategy: everything BUT crates. We score magnet balls, the bowling ball, and have a cool autonomous program. This way, we can avoid the consistency problems we've seen with the all or nothing crate lifting strategy.

Plus, since balls (and magnet balls) go everywhere on the field, we can go picking up and sorting through balls while protecting our alliance or playing defense.

Re: [FTC]: Lift systems/Time?
 

I personally think in the end Global Force is going to end up doing that as well. The lifting of crates with our current manipulator is a bit...."sad".
We can more than likely make it thought the SC Championship with what we have..but I'm not hoping for much more than that. Though I must say our magnet finding is pretty boss. It's my favorite part.

Re: [FTC]: Lift systems/Time?
 

Do you have a really fast way of picking up balls or something?

Yeah I would consider it very fast.