# of Totes WORTH Stacking?

[kachea716]

How necessary is it to build tall stacks of totes? Yes, a 6 stack of totes with a filled container is nice (42 points?), but versus for example, doing two 3 stacks w/ a filled container (48 points?).... is it worth it? What is your team thinking?

[AllenGregoryIV]

Last night in our blog we posted reasoning for the exact elevation we are trying to lift and stack.

http://blog.spectrum3847.org/2015/01...4-bar-cad.html

Summary, lift should be able to elevate an object 4.5ft. Allows you to stack a tote on top of 3 totes on the step and allows you to put a container on top of 4 totes if you are grabbing it by the lip.

[Zebra_Fact_Man]

Stacking 2 stacks of 3 may actually be quicker than 1 stack of 6, but there are only 7 totes available to each alliance (4 are shared), and if an alliance can average 1 stack of 6/robot/minute (which seems very reasonable for playoff alliances) you're going to run out of recycle containers awfully quick if you go only 3 high.

Maximize each container's value; go the distance.

[kachea716]

Originally Posted by Zebra_Fact_Man

Stacking 2 stacks of 3 may actually be quicker than 1 stack of 6, but there are only 7 totes available to each alliance (4 are shared), and if an alliance can average 1 stack of 6/robot/minute (which seems very reasonable for playoff alliances) you're going to run out of recycle containers awfully quick if you go only 3 high.

Maximize each container's value; go the distance.

But, if you have a mechanism that can take all four recycling containers to your side.. you potentially can get 168 points jut from complete 3 stacks w/ filled containers

[kachea716]

Originally Posted by AllenGregoryIV

Summary, lift should be able to elevate an object 4.5ft. Allows you to stack a tote on top of 3 totes on the step and allows you to put a container on top of 4 totes if you are grabbing it by the lip.

It makes sense that you can get another tote on a 3 stack but you wouldn't be able to lift a container on top of a 4 stack of totes which is about 4feet tall, and if the lift only elevates the (about) two foot container 4.5ft. (grabbing it by the lip and not the bottom) it couldn't be stacked.

[AllenGregoryIV]

Originally Posted by kachea716

It makes sense that you can get another tote on a 3 stack but you wouldn't be able to lift a container on top of a 4 stack of totes which is about 4feet tall, and if the lift only elevates the (about) two foot container 4.5ft. (grabbing it by the lip and not the bottom) it couldn't be stacked.

You don't have to use the same attachment point to lift the totes and containers and the top of your lift won't only reach 4.5ft from the floor. I said be able to elevate an object 4.5ft. That means your lift or arm has 4.5ft of displacement. How you pick up the totes and containers and where they are attached to that lift or arm is up to you. We'll have a video up shortly of our prototype arm, it can do all things I said.

[jengl]

I think this question depends a lot on what kind of robot you plan on building. Do you plan on making a short, fast robot, or a bulky, large robot? Speed would make multiple stacks feasible, and as soon as multiple stacks become a possibility, it is my opinion that trying to balance 6 totes isn't worth the time it takes to stack them.

[Ginger Power]

Originally Posted by kachea716

How necessary is it to build tall stacks of totes? Yes, a 6 stack of totes with a filled container is nice (42 points?), but versus for example, doing two 3 stacks w/ a filled container (24 points?).... is it worth it? What is your team thinking?

It depends on a lot of variables. Most important is how good you and your alliance partners are. When The GreenHorns and 'Snow Problem played a few matches together we found that 4 totes seemed to be the most efficient to stack for our particular robots. We both have what I would call lower-middle tier robots you would find at a competiton. That is to say, it's doubtful that we would make it to the Playoffs at a large event. If the functionality of the three robots is pretty low I would make stacks of 3. If it's pretty high I would make stacks of 5. Stacks of 6 with a recycling bin just gets dangerous IMHO.

[kachea716]

Originally Posted by Ginger Power

If it's pretty high I would make stacks of 5. Stacks of 6 with a recycling bin just gets dangerous IMHO.

I agree... in this game it's important not to play against yourself = make obstacles for your self.

[cjl2625]

I'm thinking 5 or 6, but not sure which.
I personally think the main problem with stacking 6 is that if you want to hold six totes plus a container on your robot, any appendages that high get dangerously close to the 78" height limit.

[MrJohnston]

It's going to be five or six at the highest levels.. Most likely, all bins will be scored on tall stacks in these matches. So, it would seem the tallest stacks are best... However, as robots cannot be taller than 6'6" and a bin on top of six totes will almost entirely be above the maximum robot height: A stack of 6 totes is just over 6' and needed to be lifted at least 2" to place them in a scoring zone. This leaves a whopping 4" of recycling bin below the robot height limit.

This introduces a challenging engineering problem. Do you find a way to grab the bottom few inches of a bin? Or, do you rely on a very smooth riding robot and a skillful enough driver to not "bump" anything? I have not yet fully solved this "difficulty." However, it could very well be that for nearly every (every?) robot it is so much more efficient to maximize stacks at 5 totes and a bin...

Of course, you then have to ask the value of taking a moment to stick pool noodles into the recycling bins...

[cadandcookies]

Originally Posted by MrJohnston

It's going to be five or six at the highest levels.. Most likely, all bins will be scored on tall stacks in these matches. So, it would seem the tallest stacks are best... However, as robots cannot be taller than 6'6" and a bin on top of six totes will almost entirely be above the maximum robot height: A stack of 6 totes is just over 6' and needed to be lifted at least 2" to place them in a scoring zone. This leaves a whopping 4" of recycling bin below the robot height limit.

This introduces a challenging engineering problem. Do you find a way to grab the bottom few inches of a bin? Or, do you rely on a very smooth riding robot and a skillful enough driver to not "bump" anything? I have not yet fully solved this "difficulty." However, it could very well be that for nearly every (every?) robot it is so much more efficient to maximize stacks at 5 totes and a bin...

Of course, you then have to ask the value of taking a moment to stick pool noodles into the recycling bins...

You can also stack a tote with a bin on top of it on top of 5 totes. Or two totes and a bin on top of four.

[asid61]

Einstein will be all six stackers or two six stackers and a noodler with peripherals. Or six stackers with noodler abilities. However, looking at a point chart. four totes gets you almost as much as five anyway if you can noodle it.

To stack, simply lift an existing stack and slide a tote underneath it. Most forked lifters should be able to do this to get very high stacks up to six plus bins without issues.

[kachea716]

Originally Posted by asid61

To stack, simply lift an existing stack and slide a tote underneath it. Most forked lifters should be able to do this to get very high stacks up to six plus bins without issues.

Stabilizing the container would become a problem with this? Raising the large stacks and keeping it balanced could be a problem. It's all about control.

[cadandcookies]

Originally Posted by kachea716

Stabilizing the container would become a problem with this? Raising the large stacks and keeping it balanced could be a problem. It's all about control.

This year is full of problems like this. Stacking totes "nicely" is far more difficult than just stacking them.