Team 1114 - Simbot SideSwipe

[NWChen]

Originally Posted by Karthik

Here's the video of our initial intake prototype. You'll notice the rudimentary nature of the setup; it's built with cupboard doors, old intake wheels, hand drills, and two old four caster carts.

https://youtu.be/jH4n1X1Oz7c

Very cool. Were there other approaches to intaking before this prototype? Any chance of more videos being uploaded?

[Bryce2471]

Originally Posted by NWChen

Very cool. Were there other approaches to intaking before this prototype? Any chance of more videos being uploaded?

I am also interested to hear the answer to these questions.

[Karthik]

Originally Posted by NWChen

Very cool. Were there other approaches to intaking before this prototype? Any chance of more videos being uploaded?

No, this was the first approach that any real effort was put into. There were many subsequent prototypes with different wheel spacing, wheel sizes, wheel types, tension in the surgical tubing, etc.

[JesseK]

Originally Posted by Karthik

No, this was the first approach that any real effort was put into. There were many subsequent prototypes with different wheel spacing, wheel sizes, wheel types, tension in the surgical tubing, etc.

The big lesson that carries from this year to the next is that there must be an active intake, and if the game piece doesn't conform to it then the intake must conform to the game piece. Having that design paradigm on day 1 would have set us up a bit better this year. I'm really impressed you guys had such a successful prototype on Day 3.

[Bryce2471]

Originally Posted by Karthik

No, this was the first approach that any real effort was put into. There were many subsequent prototypes with different wheel spacing, wheel sizes, wheel types, tension in the surgical tubing, etc.

If you don't mine me asking, how did you come to the conclusion that this would be the best intake to test, when you hadn't even made any previous prototypes? What was the thought process that lead to this unconventional intake geometry being your first attempt? Did you lay out the performance goals for the intake before hand? If so, what were they?

I am sorry if these questions come off to pushy. I'm just really interested in how you came to such an effective prototype so early.

Thanks again for all the information and resources that have been posted already.

[akoscielski3]

Originally Posted by Bryce2471

If you don't mine me asking, how did you come to the conclusion that this would be the best intake to test, when you hadn't even made any previous prototypes? What was the thought process that lead to this unconventional intake geometry being your first attempt? Did you lay out the performance goals for the intake before hand? If so, what were they?

I am sorry if these questions come off to pushy. I'm just really interested in how you came to such an effective prototype so early.

Thanks again for all the information and resources that have been posted already.

The thing was, this intake wasn't unconventional to a lot of us. We were expecting a lot more teams with this exact same style of intake in the season. I was surprised to see a lot less teams(or none) come up with this design (until later in the season).

The goals for the intake were:
- Fast at puling in a tote
- reorientate almost any tote, no matter what position it is in (besides up side down totes)
- Hold the tote inside our robot long enough for the indexer to pick up the tote
- Intake Cans, and upright cans

To accomplish these goals we thought that the intakes must somehow be able to pull the totes in towards us to orientate them, the wheels alone will probably not do this (We proved this later by removing the front wheels on this prototype). To pull the tote in you would need to have some sort of elastic pulling force to rotate it. THis is why we thought of the pivoting wheels on the outside. Also to make the totes go into the same position inside of our robot every time we would need to have another set of wheels that are "Fixed" (they actually can move a bit). So after coming up with the idea on the weekend, the students ran with it on Monday and came up with the prototype you can see above.

It worked pretty well at first, but we kept playing with spacing, wheels, elastic force and many other variables that we would think could affect them. After finding out the optimal things we began to CAD them, and they are now what you can see on the robot.

A few days later after the prototype we noticed that it might be possible to upright the Cans with out intake too. To accomplish this we tried adding something to make the can pivot around. Originally this was a just a 2x4 piece of wood someone would step on. We played around to find out if this was possible, and what the approximate distance from the inner wheels, this pivot would need to be. After building the robot the "Boot" as we called it, did not exactly perform as we hoped. During week one of competition (we were not competing) one of the members sketched up a rounded "boot" that would make a better pivot point, and guide the can upright. There is a picture of this in the Engineering Notebook on our website. Also to do this our intake would have to be spaced an extra 2 inches apart, which is why they have Cylinders on them to rotate inward and outward. These cylinders is why the inner "Fixed" wheels are not exactly fixed, they can be pushed outward a bit, but will move the tote back into the center of our robot when we intake it

Also you NEVER need to apologize for asking questions. Asking questions is how you learn. I would not be working on robots for a job, working on completing my Mechanical Engineering Degree and Diploma, and be a mentor on Simbotics if I never asked questions. At one point I was an eager and excited high school student who wondered all of these things too.

Ask questions, ask a lot of questions.

I hope all of this helps, and I wish you and your team a good luck in this upcoming season

[Gregor]

Originally Posted by akoscielski3

At one point I was an eager and excited high school student who wondered all of these things too.

Can confirm.

[JesseK]

That latch! Wow! How hard was it to balance the push-up force from below versus the cylinder's resistance, only to need to use the retraction stroke to then lift the entire stack in order to set it down? Was this accomplished via specific prototyping, calculations, a bit of both?

I also see an axle linking the front/rear latches on either side. Were there any issues with the left/right sets not firing at the same time, and if so what eventually solved it?

What are the 2 pieces hanging off the bottom of the claw for?

The long skinny horizontal cylinders that run front-back didn't seem to import correctly. Are they for pushing the tote stack out of the bot?

There are some really great nuggets of wisdom in the details of this CAD - from the nifty sheet metal carriage all the way down to the idler sprocket assembly design. I dunno how I would approach a rear-leaning tower without sheet metal though. It's a really neat design.

[Mike Marandola]

Originally Posted by JesseK

What are the 2 pieces hanging off the bottom of the claw for?

They for capturing the top of the stack. This picture shows it well:

Originally Posted by akoscielski3

Ask questions, ask a lot of questions.

I was given one of your worn out BB wheels at IRI and it's broached for 3/4" with a hex sleeve put in it. Why is that? Was it not originally 1/2" hex, did the plastic start rounding, or something else?

[thinker&planner]

Originally Posted by Mike Marandola

I was given one of your worn out BB wheels at IRI and it's broached for 3/4" with a hex sleeve put in it. Why is that? Was it not originally 1/2" hex, did the plastic start rounding, or something else?

I know that you can buy those wheels with a 3/4" hex broach off the shelf. I suspect that they were easier to obtain at that point in the season (they always seem to be out of stock for me).

[Mike Marandola]

Originally Posted by thinker&planner

I know that you can buy those wheels with a 3/4" hex broach off the shelf. I suspect that they were easier to obtain at that point in the season (they always seem to be out of stock for me).

Ah ok. The only reason I didn't think that would be the case is because there are voids inside the bore.

[NWChen]

Originally Posted by Mike Marandola

Ah ok. The only reason I didn't think that would be the case is because there are voids inside the bore.

In my experience BaneBots ships their 3/4" hex broach wheels with voids inside the bore - back when they were available, BaneBots indicated that voids within the core of the wheel are normal.

[Mike Marandola]

Originally Posted by NWChen

In my experience BaneBots ships their 3/4" hex broach wheels with voids inside the bore - back when they were available, BaneBots indicated that voids within the core of the wheel are normal.

That's good to know. Thank you

[cxcad]

Do you guys have any analysis that was done on your parts that you can share with us? I'm particularly interested in how you guys ensured that your robot was designed to play a full season of matches and practices for your practice bot. How do you train students up to that level of design (if you're doing analysis with the students)? That's pretty high level for most of FRC. I would assume it's the mentors doing it (ok by me), because most students don't have that type of knowledge just yet.

[Karthik]

Originally Posted by NWChen

Any chance of more videos being uploaded?

As requested, here are some more prototypes:

Indexer prototype made of VEX EDR components; Day 4
Drill powered, wood indexer prototype; Day 8
Kiwi drive prototype; Day 8