How Would You Change Your Robot
 

Now that Arial Assist is over, and people are preparing for offseason, what would you change about your robot's initial design, strategy, and etc.? What are some of the best strategies you have seen and how could they be improved upon?

Re: How Would You Change Your Robot
 

I wish our robot didn't have to open the intake in order to shoot, that was our one weakness when trying to shoot.

Re: How Would You Change Your Robot
 

make a robot capable of doing a 3 ball autonomous...or even a 2 ball...

Re: How Would You Change Your Robot
 

Still sticking to the same strategy, I think we should have pivoted our intake from the bottom (as opposed to the 90 deg setup we have now). We had a lot of problems dealing with a dead zone and having the intake pivot from the bottom would have fixed that issue. Also, I think we should have looked into a wheeled shooter more than we did. It was obviously very successful (254) and should have been given more consideration by our team.

Re: How Would You Change Your Robot
 

I would make our drive base wider. Although the 2013 Drive in a Day was convenient, 23.25" wide really hurt our intake options, (we were pretty much restricted to an el toro intake) and how we could hold the ball in (we had to use poles which really ended up hurting us in the end). The reason we went with the length that restricted the width was to get a better shot on our pneumatic shooter. I would honestly downgrade our drive train to 4 CIMs in order to prevent two things:
1) Teams that would see our drivetrain and say "You guys are playing defense" (although this may have been the reason we got to MSC)
2) The battery draw. There were a few matches where we would stutter about the field because we drew the battery charge to below 10 volts.

But hey, hindsight is 20/20 :rolleyes:

Re: How Would You Change Your Robot
 

I could go on and on and on. I'll probably make a few posts on this topic, as the answer differs depending on the constraints (keeping the same robot design, starting from scratch, etc). I will say any designer that doesn't hate their robot by the end of the year is either really, really good at their job or... not so good at it. There is always something to improve.

If I had to start from scratch again, I would focus on the following attributes above all else:

• Floor Pickup that Kiss Passes
• HP Loadable
• Lob Shot (One Zone Truss / Front of Low Goal Score)

That's it. I would have no capacity for varying shot strength to shoot from range. The effort to reward ratio isn't worth it when those shots only matter in niche situations. The only exception might be a more linear shot for trussing to a human player. There are reasons to do more than this, but this is the best and simplest focus for 2791.

Numerous ways exist to accomplish this set of tasks - even from within the "arm/claw robot" paradigm we built in this year. I think the "best" way for us to have done this would have been to have built a 254-style backspin shooter with a fixed trajectory. Instead of two intakes and an articulating shooter back, I'd want one intake (in back?) and a pop-out lexan "chute" on the other side for simpler human loading. The way the Poofs did it performs better and meets their objectives better, but this approach drastically simplifies things which is better for our team.

The "claw" intake I believe can be made better than the best "bar" intake, but it turns out at the top level, intake performance was secondary to other factors leading to a quick cycle time. So as long as the performance dip wasn't massive (and it wasn't) a bar intake is the way to go to facilitate kiss passing.

More later, if anyone's interested and I still have homework to avoid.

Re: How Would You Change Your Robot
 

We made the right choices for the most part. These areas could have been better:

-Faster winch motors/motor
-Faster intake (BAG motor on a VersaPlanetary would be better)
-Different frame (AM14U took too long to swap wheels)
-Different third stage ratio on VexPro ball shifter (we were really slow)

Re: How Would You Change Your Robot
 

Ability to quickly change out wheels quickly.

Ability to shoot with intake up.

Checkmate shooter (in front of low goal) for regionals, on the fly "line" shooter for championships. We had neither of those shooters.

More formulated strategy for regionals (i.e. drop ball in front of low goal, have parter push in, which we ran twice successfully at championships).

Mecanum wheels on intake.

6 cim drivetrain.

Re: How Would You Change Your Robot
 

Very little compared to the last two years:
-Two speed 6 CIM drive transmissions instead of 6 CIM single speed 15fps. We couldn't push without tripping the main breaker and even tripped it in aggressive driving. A low gear means we could push without stalling motors.

-More consistent, easy-to-replace catapult spring. We used stretched and tied surgical tubing which required frequent maintenance to maintain acceptable, let alone optimal trajectories. With a better material, we could have consistently had an extremely wide sweet spot.

Re: How Would You Change Your Robot
 

I think we should have focused on shooting rather than catching. Catching turned out not to be a major part of the game at the higher level, and we did not have the ability to shoot. But, as people have said, hindsight is 20/20.

For the offseason we are planning on making some changes though:

• Add more motors to our drivetrain (one extra miniCIM to each wheel)
• Possibly make our sweeper faster
• Add LEDs :D

Re: How Would You Change Your Robot
 

Or in our team's case, a one ball...

Re: How Would You Change Your Robot
 

Keeping the same "claw on arm" design:

• Make starting config position of claw able to shoot in high goal from in front of low goal
• Move as much of the claw geometry inside the frame perimeter as possible
• Move punch's "fully cocked" location about 3 inches behind ball to allow it to accelerate
• Properly sized arm gearbox with 35 chain for final reduction

All of these are fairly obvious changes - strengthens the rotational joint, makes shooter more powerful without changing the design at all, gets claw out of harm's way, gives us the only important high goal shot in the game. Maybe there is some way for a few of these (the first one) to be implemented for IRI, if we get in.

Re: How Would You Change Your Robot
 

Scrap it and use the cheesey poof's design

Re: How Would You Change Your Robot
 

I would have added some way to forcefully eject the ball from our catching mechanism (e.g. not gravity-powered), preferably upward and into the high goal.

Re: How Would You Change Your Robot
 

Having a dedicated inbound/defense bot was reasonably competitive but not a lot of fun especially when paired with a weaker alliance.


PID for pickup actuation. It worked well in practice but it wasn't robust enough for competition.


Using a jvn style instead of a "drop down" intake.

A woven carbon fiber tube for a goalie bar instead of a pulltruded one that split along its grain.

Re: How Would You Change Your Robot
 

1. Be able to effectively score the low goal. We could push the ball in when it was on the ground, but once the ball was in our bot it was difficult to expel it by means other than the shooter.
2. Faster, more robust pretension adjuster with greater range. I think our bot could probably human to human truss if we could crank the spring pretension up some more.
3. 2 ball hot auton. We have a pretty consistent one ball hot auton, and our bot can do a 2 ball in theory, but we haven't had time to implement it.
4. Be able to shoot the high goal from the low goal. Since we have on the fly pretension adjustment, and can adjust our release angle between matches we can probably do this if we find the right settings. This would have been useful for matches where we were playing finisher instead of trusser.
5. Goalie bar. We didn't think this would be worth it initially, but once teams started using webcam control for goalie bots in auton it was obvious that it could have been a great addition to our bot, and we probably had the weight for it.

Re: How Would You Change Your Robot
 

For reference, our robot was a low goal robot, had a one ball hot auto, and could catch every so often (slightly more by skill than by luck), given a good soft lob.

1. Get more replacement wheels. Our auto missed a couple of times because our wheels wore down and went less far during auto than we intended.

2. A goalie pole. I didn't see a single goalie pole at MARCMP, and it would have gone a long way towards bringing us further.

3. More reachable CRIO. Our robot always had some problems with dying every so often early in events. It would be nice to design for not dying.

Re: How Would You Change Your Robot
 

Launch the ball with something with more surface area than our erratic catapult.

Re: How Would You Change Your Robot
 

Would have done single speed drivetrain of about 18 FPS

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Change the intake roller gearing so that is is slower. They provide just barely enough force to pick up the balls as is.

Re: How Would You Change Your Robot
 

This isn't a change, but I wish myself and my team would've prototyped one or two wheeled shooters. That thought hadn't even crossed our minds as an effective way to shoot. But it evidently was, as 254 showed us all.

Re: How Would You Change Your Robot
 

SKYSTALKER but better

Enough said.

Re: How Would You Change Your Robot
 

-Faster catapult reset
-not having a variable hard stop
-able to shoot with intake in frame perimeter
-modified our side plate design because doing anything by the wheels or chain was a pain in the butt because we had c channel plates

Hex shaft for our thrower arm instead of standard rod. Would have solved so many of our problems that caused us to fail miserably at Peachtree

Re: How Would You Change Your Robot
 

Perhaps a shot into the high goal when positioned up against the low goal. Several strategy options open up given that ability. We saw the shot angle out of Barrage able to consistently put a ball into the high goal not only positioned up against the low goal, but up against another robot against the low goal as well.

Moreover, at Archimedes, I know a lot of us were very impressed when the eighth seed alliance used a strategy we had considered to take them to semis and almost to finals, where one robot would sit at the low goal the entire match and receive inbound passes from a human-player, shooting the ball into the high goal and putting up consistently high (300+ clean points) marks.

Imagine a long sweet-spot shot combined with a reverse-shot from the low goal so long range scores are possible, but if we get engaged in a pushing match, we can back out and pivot straight to the low goal, and score it for the full 40 points instead of settling for 31, plus we wouldn't have to turn to shove the collector into the low goal for the dump. Only problem is we have a tall back flap that gets in the way but we could always reinstall our shorter one.

Its nice to dream... eh? I bet we could add another mechanism with the 5 pounds for IRI... Then again, it would probably have to be made of neoprene or balsa wood to fit within weight constraints :p

And what else? The sky is the limit. Maybe a dual collector for three ball autonomous? Maybe add a gyro for super cool auto modes? Put the camera back on the robot? Notice those improvements all have to do with the autonomous period. I'm a programmer, what else would I want?

Probably the simplest improvement would be to add one of those driver precision flashlights, because they look sleek and seem useful for alignment. Even then, indicator LEDs that change based on our catapult state machine would be nice. We had those nearly operational earlier in the season!

Re: How Would You Change Your Robot
 

- Made the changes that we did before our third district. (low goal dump/over the top kiss pass)
- Skip mecanum drive on a non-rectangular chassis. Getting pushed around the field isn't so fun.
- Got the camera/hot goal working earlier

Re: How Would You Change Your Robot
 

We did. We regretted. You shouldn't.

Re: How Would You Change Your Robot
 

Singles speed was just fine. 18fps, probably not. I think in a lot of cases it's more important to design for acceleration and time to distance than it is max speed.

For us: actually build two full robots. We swapped the manipulator arm every regional and it hurt our practice time and introduced more troubleshooting that was necessary. Would have been better to do it all the way (like we intended starting off).

Re: How Would You Change Your Robot
 

Can't say there's too much I'd want to change on our robot; I'm really happy with how we performed at CMP.
Maybe a short shot from the 1 pt box would be good.

But if there's one thing I'd request, it would be a magic gyro that doesn't screw up. We've lost matches due to gyro problems, and then our field-centric swerve drive doesn't behave.

Re: How Would You Change Your Robot
 

Can confirm, hex shafts are the way to go.

Re: How Would You Change Your Robot
 

Assuming we're going with the same basic design:

• Decouple the pickup and shooter mechanisms. Our shooter springs were inside the arms that had our pickup rollers on the end, and this caused much weirdness when we wanted to pickup with the shooter cocked. If we had to redo it, I'd have gone with a more standard linear punch than our slingshot design.
• Remove the open/close of the shooter/pickup claw. This didn't get us much except the ability to catch, which we never used once, and a LOT of headaches with our lead screw and sensor. We could probably figure out how to make it able to shoot and pickup with changing the openness of the claw.

In other words, I'd try and make our robot a lot more like the H.O.T. Team's bot - they certainly seemed to be one of the most effective implementations of the two-sided pivoting claw/arm/pickup/shooter design this year (which very few teams seemed to do!). Ultimately our biggest problems were trying to do too much and making our systems too integrated to the point that if one function failed, many others would as well.

Re: How Would You Change Your Robot
 

Our sweet spot was carefully designed to be from against the low goal, to 36" (+ a bit) back from the low goal. Also our shot was designed to leave the front of the bot 60" in the air. Few things made me happier than those times when we shifted into low gear, pushed a defender into the low goal, and then scored over their heads :D

Re: How Would You Change Your Robot
 

We underestimated the weighting of assist points. I wish that our robot could have passed the ball back through its intake, instead of having to shoot it out. We also had a very short distance between tie points for our elastic bands. If we had used a longer distance I think our accuracy/precision would have greatly increased.

Re: How Would You Change Your Robot
 

I think one aspect we wish we could change is our ability to spit the ball back out onto the floor for a mouth to mouth pass. Once the ball is fully in our shooter it needs to be shot out of which we can do a full powered shot, soft shot, and a nice 1 point dump into the hopper of another robot. There were many times where we planned for the mouth to mouth and partially sucked the ball onto our bumper but once it was fully in the ring it was coming out through a pickup.

There are a few instances where it would have helped our strategy but what it mainly hurt was how teams ranked our robot which I felt contributed to us falling so low in the pickings in our division. We ended up working with three amazing robots and even if we didn't make it as far as Einstein I wouldn't have traded the experience we got from working with Nemesis, Torque, and Winnovation but we know the fact we couldn't spit it out once it was inbounded caused a lot of teams to second guess our robot being on their alliance.

This wasn't just a championship thing we noticed it all season when partners gave us a funny look that we couldn't spit out of our shooter. While designing we had prototyped our pickup that it could grab the ball and pull it out or use the back pickup to help push it to the front roller but once the final robot was assembled the ring had a different geometry than was prototyped.

Just like last year even though our robot was crazy and we may have missed some key concepts in the game like ground pickup was better than 20 extra climb points in 2013 or quick low passes coupled with some nice long catapult shots is better than accurately being able to throw the ball to your partners or yourself. In the end I still support our 2013 and 2014 robot designs as they keep pushing our team to do crazier things (that work!), set us apart from your everyday robots, and have their own elegance coupled with simplicity.

Re: How Would You Change Your Robot
 

Adding to this, I would have preferred metal springs on the robot instead of the elastic spring we used. It was too sensitive to heat difference (even between practice field and game field) and required a huge amount of effort to keep dialed in. I also would have gone to 6WD sooner in the year, rather than waiting until Championships to make the swap. Passing was key, and we didn't design for it.

Oh, and our bumpers + bumper mounts were trash all year long, even after 4x iterations between events.

Re: How Would You Change Your Robot
 

We would have added a way to do a shot from in front of the low goal, and a way to potentially pass the ball. Overall, we were very happy with how the robot performed. We actually never had any problems with surgical tubing this year, and the surgical tubing at championships was the same that was on the robot before bag day.

Re: How Would You Change Your Robot
 

Correct me if I'm wrong. but you have the surgical tubing running under the entire length of the robot when stretched right? I think that if we had done that our shooter would have been more consistent.

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It was about 4 inches when slack, and about 10 when fully stretched.

Re: How Would You Change Your Robot
 

For the most part I think we had a good design this year. (Double intake that worked really good) I do not think we played to our strenghts and execuated strategies like we should have.

1. No Mecanum drive, never ever again- getting pushed around stinks. With that we are currently working on our first WCD for an offseason project.

2. Not having to turn sideways to shoot. Caused us to not have reliable auto.

3. Improving ease of bumper mounting. Hopefully the WCD will change this.

Re: How Would You Change Your Robot
 

If I could do it over (with the same general robot design) I'd probably try to get a roller intake on my robot. Our forklift worked decently well, but a better intake would have made our robot so much stronger.

As far as strategy goes, I would have had my team/alliances start passing back the inbound to the human player during our first regional, rather than at SVR.

Re: How Would You Change Your Robot
 

Wide robot config.

Re: How Would You Change Your Robot
 

I can't complain much considering that we are walking away with 3 blue banners, and a division finalist

Things I would have changed:
-Use wheels with tread
we used kitbot wheels and they wore down so much we needed to replace them every competition, we have gone thru 36 wheels this year.
-Shifting Gearbox
we were neither fast or slow so we couldn't push thru or run around defense making it hard to get to our sweet spot.
-be able to shoot with collector and shoulder in
our robot had the shooter actuate outside the frame to provide more room for longer arms. This caused G28 calls in our first two evens(wasn't a problem in 3-5th) we originally decided that we needed the ball to be touching the intake so we could eject the ball but we have seen some clever ball ejection mechanisms.
-faster intake gearbox
our gearing was perfect for our two ball auto but it would have been nice to pick up a little faster in teleop

Re: How Would You Change Your Robot
 

Our robot this year was an octogan. I would not have made it an octogan.