Sunday, February 23, 2014

Day: 51: Inspiration

We took a short break after bag day and didn't meet on Wednesday. We met Thursday but only really looked at reveal video and did a little work on the practice bot to reattach some of our withholding weight for testing. Friday and Saturday were spent volunteering at the South Texas VEX Championship. We helped setup the event and then we were referees, score keepers, and part of the field reset crew. With over 60 teams there it was a huge event. We had four fields running at once with a single division. The winning alliance was led by teams from Galveston.

There is currently a thread on about inspiration and generating new ideas from old ideas. We want to take this time to acknowledge of a few of the places were gained inspiration for some of the features on Infrared.

Ri3D Boom Done Team: If you look at our robot, you can see the overall structure of the systems is inspired by Boom Done. Dr. Joe Johnson and his team put together an extremely effective robot in only 3 days. We were really impressed by its versatility and that it had the potential to meet nearly all of our design goals. We had been building prototype catapults and punchers but we were worried about being able to implement systems to provide a wide variety of shots and passes. We also wanted an open top design with a back panel that would allow us to easily catch balls from the human player and possibly other robots. Boom Done's overall structure met these goals. We also knew there were a lot of places for improvement after all it was designed in 3 days and we had six+ weeks. The collector was one of highest priorities; we wanted to be able to get the ball off the floor as quickly as possible. We also knew that leaving the collector deployed would increase the risk of it getting damaged and it wouldn't allow the ball to be secured. We went through at least 4 major iterations on the collector before we got to the non-pivoting independently dropped down, Mecanum collector that we have today. We added wings to the side of the tower to help with catching and to secure the ball even more then we drive. We also knew that the launcher could be improved, because its motor powered we figured that if we added more motors we could increase its acceleration and thus increase the balls exit velocity again giving us a wider variety of shots. We prototyped the shooter using a 3 CIM gearbox that we had used on our previous year's drive train. We replaced one of the CIMs with two 775s to give us even more power. We have been experimenting with constant force spring on the launcher bar to help with acceleration even more but there are some draw backs, such having to lock the launcher down instead of just having it rest at any point.  Our drive train is also different but that was inspired by another team.

Team 3928 Neutrino and Aren Hill: We didn't use the choo-choo mechanism that many people are so found of that Aren Hill demonstrated this year but we were inspired by a drive train that he helped design last season. Neutrino's butterfly modules were extremely impressive when we were pit neighbors with them this summer at IRI. The simplicity of just pushing down on the module and having it sprung up on its own was very cool. Our original plan was to use their shifting concepts in an octocanum configuration but we ended up back at butterfly after a few problems. We modified it to allow us to add MiniCIMs to each module and also include 2" wide traction wheels. Another difference is we put our omni-wheels to the outside of the frame which makes our traction drive a little less stable but it does allow it to turn better.

Sheet metal Designs of 148, JVN, and many others:
We have been learning about sheet metal design for the past two seasons. When we first got into it we looked really closely at the Robowrangler robots from previous years, like Raptor and Tornado. We also had a huge number of our questions answered by JVN. Since then we have been improving and had a student learn to run the laser and the break to cut and bend all our parts. These two threads on chiefdelphi provided a huge amount of advice on solid drive train design. Thanks to the mentors from 971, 973, 488, and others.

610 Helpful Tips:
We posted about this earlier but this thread on Helpful hints for all is a great read. Because of it, we added an attached velcro strap to our SB50 Battery connector, we stood off our Power Distribution board from the belly pan to allow us to mount things under it (Radio power inverted and lights), and we added wire rope and pneumatic tubing handles (These might be the best feature on our robot). In a different thread Mr. Lim of 610 led us to these potentiometers. They are continuous rotation single turn pots, and we use one our launcher and they've been great.

On board volt meter from team 1818:
This is one of the best features we have put on a robot-- it weighs almost nothing and just plugs in to our terminal strip for the lights. It couldn't be simpler. We bought ours from overseas but Adafruit and others sell them. We expanded this concept to the entire back panel of the robot, which is the central display for all the information on the robot.

Our last two robots have relied very heavily on VEXpro products. Nearly all the gears, sprockets, and pulleys on Infrared are from VEXpro. Their Versaplanetary gearboxes allow for some extremely nice designs because of the reduction you can get in such a small package. 

Thank you to all the people that have inspired our design choices and more than anything taught us cool things-- that's one of our favorite parts about the FRC community.

- Spectrum

"It's a great thing, for someone to feel that they can draw inspiration from you." - Chloe Sevigny

Wednesday, February 19, 2014

Bag Day: Infrared


Reveal Video

Reveal Photos

To discuss the robot head over to our CD thread.

It's in the bag.

 The handles even work when it's in the bag.

We withheld the collector, the launcher bar, the traction wheels, and a few other things. Lots of things to iterate over the new couple weeks.

- Spectrum

“When I am working on a problem I never think about beauty. I only think about how to solve the problem. But when I have finished, if the solution is not beautiful, I know it is wrong.” - Buckminster Fuller

Tuesday, February 18, 2014

Day 45: Filming

We started the day trying to get through a few problems that have crept up on the competition robot. Nothing too major there was a popping noise in one of our drive modules that we have discovered was a bearing rocking in it's seat. We also had some issues with getting as a consistent shot as we want but found a few options to make that better.

We filmed most of our reveal video today. We'll film a bit more tomorrow afternoon before we bag and should have it up sometime on Wednesday.

Around 8pm we received a call from a local team, 4155 SHARC, because they were having trouble getting their cRIO to image after breaking the sidecar. We actually had them bring their electronics board to our shop and we found that one of their students had mistakenly wired their cRIO to 12v instead of 24v. Surprisingly it will still work pretty well, except it won't take an image and will have other random errors, but it does boot and the imaging tool can find it. Once we found the cause of the problems, we got them squared away and they should be practicing again tomorrow.

For one reason or another this photo was taken during filming of the reveal video.

- Spectrum

“You should bring something into the world that wasn’t in the world before. It doesn’t matter what that is. It doesn’t matter if it’s a table or a film or gardening — everyone should create. You should do something, then sit back and say, “I did that." - Ricky Gervais

Monday, February 17, 2014

Day 44: The robot is complete (except for all the iterations we still have to do)

We had the competition robot driving and shooting today. At first the robot was doing something very interesting: it was shooting straight up in to the air. The ball would actually land back in the robot. This was not the intended result. We figured out that our launcher bar for the competition robot wasn't bent at the correct angle and it was just a little shallow. We bent it a few degrees more and it's shooting better than the prototype. Collection is about as good as we could ask for. We have over a 180 degree window for the ball to hit the collector sticks where it will still collect.

Tomorrow will be spent programming and filming our reveal video.

We also talked about strategy and scouting again today since we were able to watch some of the webcast from the scrimmages from around the country. One of the main points of debate was what is important in this game. In most games shooting percentage and shots taken are two of the most important stats; last year you wanted robots that could get Frisbees in the goal. This year it's different since each alliance only has one ball; we have to use stats that are more similar to traditional sports like soccer, basketball, football, and rugby. In basketball a very important stat for point guards is your assist to turn over ratio, which basically says how good you are at setting up your team mates for points with the ball in your hand. We think that a similar stat in Aerial Assist can be Assist Generated to Lost Ball ratio, we want to compare how often a team generates an assist by passing to a team mate to how often they lose the ball. Lost Balls can occur in many ways: dropping the ball while driving, missing a shot, throwing a truss pass that isn't quickly secured by a human player, team mate or the same robot, or any other way that the ball gets out of control of that team. Lost balls are going to be time killers for teams and cycle time is the most important thing for an alliance. Ball recoveries may be another important stat because you want teams that are able to recover a lost ball quickly and reliably. We're also going to be keeping track of things like inbound catches, tackles, deflections and much more. Since not every team needs to score, advanced metrics will be even more important this year.

We wrapped up our practice open lab today by having 4 teams in our shop working, practicing, and getting ready for their events.

We have had people working 41 hours over the last 3 days. We have another 10+ hour day ahead of us tomorrow.

- Spectrum

"The losers are the ones caught up in that afternoon rush hour. The winners drive home in the dark." - Neal Boortz

Sunday, February 16, 2014

Day 43: It's really pretty

We have spent way more time making sure that everything on this robot is in the right place and looks good this year. Last year we had a lot of little issues because something would come unplugged or get plugged in to the wrong place. That won't be happening this year.

We're also doing 15 hour days today and tomorrow. Last little bit of time with the competition robot before we put it in the bag.

That's just a small corner of the robot, the theme this year is #AllWhiteEverything

We're pretty sure we are going to be slightly over weight like 121lbs after we add the MiniCIMs and 2" wide traction wheels to the robot at our first event (we're withholding them so we don't have to buy spares). So we are going to have to go on a small diet and remove some less needed things here and there.

The first day of our open lab / practice day was a very big success. We had two rookie teams and three veteran teams in our shop today working on their robots. Some of the teams need help with construction and others just need a place where they can stay late to finish their robot. We're happy to help either way. The last weekend push is hard no matter what, and we're happy to make it a little easier for some teams.

- Spectrum

“If you can dream it, then you can achieve it. You will get all you want in life if you help enough other people get what they want.” - Zig Ziglar

Saturday, February 15, 2014

Day 42: The last push

Today was the first of 4 straight 12+ hour days for us. Our school's schedule works out very well and we always have a 4 day weekend for presidents day.

We spent most of today wiring; we won't know for sure if this is our best robot till it plays some matches but we can already tell that this is our prettiest robot. Lots of little details are getting hammered out, not many major changes, though we did change the location of our solenoid mounts.

We are moving to VEXpro traction wheels with rough top tread along with our omniwheels in our Butterfly drive. We tried the new Versawheel DTs but sometimes you shouldn't mess with what works. The 2" wide traction wheels have far more traction than the versawheels, it's not even close. When combined with our 8 motor drive train the acceleration in low gear makes it look like our robot is going to take off. We'll be adding some ramping functions so the drivers can keep the front wheels on the ground. The traction wheels are actually about 4.25" diameter once we mounted the tread on which caused some issues in our wheel wells so we had to turn down all of our standoffs to 7/16" instead of 1/2".

We had Discobots in the house tonight and they'll be working at our place all weekend. We'll also have at least a few more teams over for the Houston practice session. We don't have much of a field this year, but this game is sort of like soccer: all you need is some carpet and a ball and we should be able to practice.

- Spectrum

“Do the best you can until you know better. Then when you know better, do better.” - Maya Angelou

Friday, February 14, 2014

Day 41: Five Days Left + Chairman's Award

Spectrum 2014 Chairman's Entry

That's our 2014 Chairman's entry for this year. We have put in a lot of time working on it and way more working on the activities that we talk about it in. The Chairman's Award is FIRST's highest honor and something all teams should strive for.

Sorry for not having an update yesterday, nothing really exciting has happened. We're assembling the competition robot, putting some of the bumpers together, and getting ready to spray paint some of our other parts.

Here's a quick picture of our wiring for the competition robot. We're still not as good as some of the west coast teams (254, 968, 1538, etc.) but we're pretty happy with it. This is still missing pneumatics, sensors, the main breaker, and a fewer other things, as well as three talons, which will be withheld with our practice bot and the MiniCIMs that attach to them.

- Spectrum

"I hope you're proud of yourself for the times you've said 'yes,' when all it meant was extra work for you and was seemingly helpful only to somebody else." - Fred Rogers

Wednesday, February 12, 2014

Day 39: Parts are finally back

We got all the parts back from the powder coater today, sadly there won't be any purple powder coat on our robot but the white still looks good. There will probably be a few purple spray painted items as well.

We started final assembly and have gotten pretty far along. We have the full drive train complete and waiting for electronics. We have most of the back panel assembled just need to add the two launcher shafts.

With the 45lb withholding allowance we won't be bagging a collector, wings, or launcher arm so we'll have plenty of time to work on those before our first event, Week 3 in Dallas. All of those mechanisms are very modular and should be very fast to reattach at the event.

- Spectrum

"I have seen many people become good at copying, but then never think to apply what they learned to their own drawings. Applying something from what you study tests you to see if you actually understood what you copied." - John K

Tuesday, February 11, 2014

Day 38: New Collector but no powder coated parts

We didn't get our powder coated parts back today. We have been assured tomorrow. The assembly should only take 3 days but it would be nice if we had all weekend to work with the robot.

We did however get our last run of laser cut parts. Included in this run was some plate hex hubs, some mounts for the pneumatic cylinders in the drive train, and some new collector parts.

Here is the new collector mounted n the robot. It may look the same but it's designed not to rotate anymore. We also finally moved to using 775s on the collector which was the plan all along. The 775s have nearly twice the power that the BAG motors do. That puts our motor count this year up to 6 CIMs, 4 MiniCIMs, and 4 BB775s. We really like our collector for a few reasons, particularly because we don't have to stick anything out past our bumper except for the wheels and hex shaft. We're still a bit worried about bending the mounts but we are working on ways to prevent that. The pneumatic cylinders are very low on the pivot and allow the shafts to be pushed back very easily which means they don't bend or break if we run them into a wall. We can also collect when the ball is off center and we can easily eject the ball forward out of our robot to pass or score in the low goal.

Tomorrow should be basically all assembly and more chairman's award work.

- Spectrum

“If your actions inspire others to dream more, learn more, do more and become more, you are a leader.” - John Quincy Adams

Sunday, February 9, 2014

Day 37: Everything is ready

We prepped all the parts we needed for the construction of the final robot. Every little spacer is ready to go and should make final assembly very quick.

We had more friends over today. This afternoon we were joined by the Discobots at our build site. They ended the day by getting some good test shots out of their robot.

We did a bit more programming today and worked on the vision code that will allow us to detect which goal is Hot in autonomous mode.

We worked a bit more on the launcher but never got the consistent 18ft shot we were looking for. It's not crucial for our strategy so we'll be stopping the pursuit until we can ensure the rest of our priorities are accomplished.

We finished up the CAD models for our week 6 laser run. It will include a few new parts for our collector and also some replacements for our pneumatic cylinder mounts on the drive train.

The Chairman's essay is now finally under 10,000 characters but it's always a struggle to keep it that way. We have so much to say and so little space.

- Spectrum

“Trust your passion, identify your dreams, and find the courage to share them with others, no matter how many times they call you a fool.” - Bill Strickland

Day 36: Programming, Friends, and Fundraising

We did a lot of work on programming today.

We added in our IR sensor to detect the ball. This allows us to automatically stop our collection and catch commands once the robot sees that we have the ball. This makes catching and collecting much easier. It's extremely simple code; basically if the sensor sees something within a certain distance it just stops doing the commands. Very simple but should be very beneficial.

We added in our PID position control for the launcher arm. We have added about 60lbs of constant force springs to our launcher so it no longer rests in the down position. We might be removing a couple of those to fix this but we still needed a way to force the launcher to return down after we fired. We do have a potentiometer on the arm so that it know how to return to the stowed position.

We finished turning several of the pieces for the real robot, mostly just standoffs and spacers but they're very crucial for proper alignment.

We had a few friends over today. Team 4280, N-GEN from Sam Houston Math, Science, and Technology came by and we helped them with some electronics and worked with them to get their bumper frame built. We had team 3666, Bolton Bear Bots, from Alexandria, LA come by to get in a little bit of practice on real FRC carpet. We have been working with them on several items this season and generally just sharing ideas. It was very cool that they had the chance to drive all the way out here work with us today.

At the end of the night we got to do some shooter tests in our gym. It's working very well. Our 18 ft shot still needs a bit of work but we're confident we can get it consistent soon. Here are a few of our test shots over the truss.

On a different note Team 987, The High Rollers, have started putting together an absolutely amazing video series on how their team operates. They have been consistently one of the best teams in FRC on a robot and organizational level. Here is the thread about the series and the first video is below about fundraising. Thank you 987 for putting these together, many teams will benefit.

- Spectrum

"Synergy — the bonus that is achieved when things work together harmoniously." - Mark Twain

Saturday, February 8, 2014

Day 35: Launching Better

We spent the day gathering all the parts for the competition robot. We still don't have the sheet metal back yet but that should be Monday. We want to have everything else ready to go when we get it back, and it should go together like a big Lego set.

We also replaced the belt on our shooter with sprockets and chain. We now have 2 CIMs and 2 BB775s driving a 5.33:1 VEXpro gearbox, that has a 12 tooth sprocket driving at 26 tooth sprocket that share a shaft with 2 15 tooth sprockets that drive 26 tooth sprockets on each arm of the shooter. Our final gear ratio is right at about 20:1. With the chain we have to be much more careful not to stall the motors into a hard stop.

We also started testing different release angles by adding a bar to the launcher arm at different points. This dramatically alters our shot trajectory and can provide us a much further shot. We're going to play with this more to find the optimal position.

A few minor things as well, we got more air tanks and the real mounting brackets from Pneuaire, we mounted them on the practice bot and had to modify the mounts slightly to make them work the way we wanted. We also put on the 3D printed pot adapter for the launcher and that didn't work as well as the makeshift one we had before. We'll have redesign a bit to make sure that it's very robust. We changed the outward angle of the wings by adding a small spacer to the cylinders, which prevents them from pulling any further out.

Here is a quick video of us testing the ability to drive with two balls. I wonder why we would want to do that?

- Spectrum

“When in doubt, always err on the side of generosity!” - Ping Fu

Thursday, February 6, 2014

Day 34: Withholding allowance and 3D printed parts

We're sort of just waiting on the parts to come back from powder coat at this point. Lots of little things going on but not much major work. We're reworking the launcher and have added springs to make it easier on the motor to accelerate to top speed. We still have a lot of programming to do before we're sure we can make all the shots we need.

We're also making sure that we will have all the parts for the competition robot ready to go once it comes back.

We also discussed our "artist formally know as the withholding allowance". The GDC has changed the rule to 45lbs due to inclement weather around the country. We actually weren't planning to withhold that much this year, but with the new rules we probably won't be bagging our collector and launcher bar. We'll have a full drive train and tower in the bag, but we should be able to make lots of modifications to the other parts of the robot.

These are some of the 3D printed parts that we have been using this year. There will be a few more as well. We're finding lots of interesting ways to make parts with the 3D printer this year.

- Spectrum

"So often people are working hard at the wrong thing. Working on the right thing is probably more important than working hard." - Caterina

Day 33: Fixing our mistakes

Sorry for no post yesterday, we had a really short meeting since there were parent-teacher conferences. Mostly worked on chairman's award stuff.

We'll start with a video today of us doing some catch testing. We're not really planning to catch that often but we think we're pretty decent at it. If there is defense it might be a different story, which is why we might not be catching very often.

We also received our new proper 4" mecanum rollers today. We're still not sure if we will be switching back to octocanum or not but the new rollers look a lot nicer than the ones for 6" wheels. We'll probably do some side by side tests once we have the competition robot up and driving.

Our shooter has been slowly getting worse since late last week and we weren't really sure why. We had been making some changes on the upper assembly, but no one really looked down at the first couple stages because we figured well, how could those be breaking? We were very wrong.

That is a picture of the belt that drives the first stage of the launcher. Apparently you really shouldn't ever allow your belt to ratchet since you can just rip the teeth clean off the belt backing, we now know that from experience. We moved the belt around to where the bad section wasn't engaged during launch and we got all our distance back. The ratcheting was happening when we didn't have limit switches or other sensors installed on the launcher and we were running it into a hard stop. Now that we have more sensor feedback we shouldn't have this issue anymore. We still might move to chain just to be safe.

We received our bigger bore cylinders,1.5" bore x 1" stroke,  today for our drive train. Somewhere in the design of our drive train we forgot to do some basic math on the leverage needed to lift our robot and now were paying the price by having to redesign to fit the larger cylinders. Had we just moved the point on the modules that the cylinders push down, we wouldn't be in this mess. We made a pretty poor system today which will get us through some testing, but we'll have a more complete fix ready for the competition robot.

We spoke with our powder coat sponsor and they say it will be done by Friday or Monday. We're hoping for Friday but we know we can assemble the robot in the last week if we have to.

We've fixed most of the problems that cropped up over the weekend and we're happy with where the competition robot should be once we get her built.

- Spectrum

"The willingness to share does not make one charitable; it makes one free." ~Robert Brault

Tuesday, February 4, 2014

Day 31: More mecanum news & catching video

This morning we got a call from VEX explaining that they had intentionally shipped the incorrect rollers with the 4" mecanum wheels so that they could get the product out faster to teams. The rollers they shipped are for the 6" wheels and thus don't provide a completely smooth motion. This is why we were able to break one since 100% of the load ends up on the tips of the current rollers during part of their revolution.

We worked more on collection today. We strongly believe that collection will be more important than shooting in this year's game. Having a fast and reliable collection system alone will allow you to play in eliminations.

Here is some quick video of our robot catching bouncing balls. We're hoping to be able to chase down balls that are bouncing anywhere on the field and catch them instead of having to collect them, which should be faster.

We're still using the mecanum wheel collector. We tried to build one out of 1/2" schedule 80 PVC but the mecanum wheels out performed it by a lot. We're going to keep trying different wheels and rollers but right now the mecanum wheels are working really well.

- Spectrum

“The best creative solutions don't come from finding good answers to the questions that are presented. They come from inventing new questions.” - Seth Godin

Monday, February 3, 2014

Day 30: When life gives you mecanums

Well today was interesting. We started the day by taking off the mecanum wheels from our drive train and replacing them with the omniwheels.

We have the robot set up so that we can remove the end caps of the chassis easily to work on certain parts of it.

We also made our collector not pivot outwards. Originally we thought the collector would need to expand to allow the ball through, but after testing we started reducing the swing more and more. Now we think we can build in enough flex and compress the ball enough that the system won't need to expand. This will eliminate a degree of freedom and make the system much simpler.

While doing this we decided to test different wheels for collection. We tried the set of the mecanum wheels that we had taken off the drive train, because we're trying to make the most of the items we have on hand. Even though they were intended for a much different purpose, they worked surprisingly well. The mecanum wheels are very grippy on the game ball and they are actually making the ball go into our robot better than some of the other wheel choices. We still have a lot of testing to do before we decide on a final roller, but mecanums are currently in the lead.

That last shot shows our backwards tipping point on this robot, so we don't think we'll have a tipping problem. The wings are still very rough, but they are doing their job.

We put the potentiometer on the launcher today and should be able to get the encoder on in the near future. The plan is to use the encoder as a velocity sensor and the potentiometer to set the release point.

We added an encoder to one side of the drive train and may add one to the other if we find a need for it.

- Spectrum

“You may encounter many defeats, but you must not be defeated. In fact, it may be necessary to encounter the defeats, so you can know who you are, what you can rise from, how you can still come out of it.” -  Maya Angelou

Sunday, February 2, 2014

Day 29: Mama said there'd be days like this

This is a hard post to write. It's just been one of those days where nothing goes well. We had some problems yesterday but we were pretty optimistic we would be able to fix them without too much trouble. Things didn't get better today.

From bad crimps to breaking a handle on the robot to diagnosing a drive train problem for 40 minutes only to realize it was a dead battery, nothing went our way today. We would try to improve things only to make them worse. The current state of just about every subsystem is markedly worse then it was 36 hours ago.

The biggest problem of the night came at around midnight when we were testing our latest change to the collection system and getting ready to test driver centric control. We were driving along fine, we strafed right and then when we went to strafe back left we saw the robot sort of dip and then just completely stop moving. We strafed back and it sort of worked but in a big arc. We thought we might have unplugged a speed controller or gotten something jammed in a gear. When we turned the robot on it's back to see the drive train we discovered that we had broken one of the rollers clean off our VEXpro 4" mecanum wheel.

We haven't done much to these wheels at all, we have only had them for 6 days and have driven less then an hour and half on them on FRC carpet only. They haven't been put up against other robots or had any pushing tests done with them, we have just driven around and tested collection for the most part. After looking at the broken wheel we found that the roller didn't spin at all, we checked all the other wheels and have found at least five other rollers that either don't spin or are very tight.

The six of us that were still at the shop at midnight discussed it and unless there is some very strong reasoning by the rest of the team to stay with mecanums, we will be switching to butterfly for this year's drive train. If this were to happen during a match we wouldn't be nearly as effective and the ability to strafe isn't worth the risk or breaking wheels and having to make repairs.

To top off the day of everything going wrong, on our way down from the third floor where our practice area is to our lab we ended up on the first floor. Our lab is on the 2nd floor, literally nothing went right today.

Tomorrow we'll change the wheels back to omniwheels, and we'll halt development on holonomic control and sensors. This may turn out to be a good thing, without worrying about mecanum wheels and holonomic control we'll have more time to focus on other systems. That's at least how we're going to spin it.

15 days left to get it right, tomorrow should be better since we get to watch the Superbowl as a team and have some fun.

- Spectrum

"Sometimes adversity is what you need to face in order to become successful." - Zig Ziglar

Saturday, February 1, 2014

Day 28: Full Robot Demo for FLL Team Visit

We started the day off with a visit from one of our local FLL teams, from The St. Thomas More School. These students were all 5th through 7th grades and they were all very interested in the robot. Surprisingly some of the questions took a very technical turn and we started talking about the difference between an FPGA and a general purpose CPU. One of the students even told us about his favorite Linux distribution and was pleased to hear that we would be switching to developing in Eclipse next year.

Here is some video of the robot collecting and shooting for the students. Our practice area only has 10ft ceilings so we couldn't shoot very hard but you can get an idea of what the competition robot will hopefully be able to do.

After the demo we started investigating the problem we found yesterday with the pneumatics on our octocanum modules.  We believe we didn't account for the lever action of the module and the amount of force we put on each cylinder. Our plan is to move to 1.5" bore cylinders but that will take a bit of rework on the mounting, though not too much. Luckily we have a working robot this early so we can catch major and minor problems before we get to competition.

We worked on adding our wings to the robot, which will help us secure the ball while driving, prevent it from slipping out while collecting, and allow us to catch passes. The current wings are made of hardboard but we are planning to move to corrugated polycarbonate. The corrugated polycarbonate was suggested to us by our friends James Tonthat and Scott Rippetoe from Texas Torque FRC#1477. It's apparently used very often in greenhouses but you can get it at a variety of plastic distributors. It's rigid like 1/4" Lexan but much lighter.

We are working on an extremely cool way to hook up an IMU to the cRIO to get an accurate heading. When it's all said and done it should only take a single PWM cable hooked up to a digital input pin on the cRIO. We'll have more on this later.

The last thing we did for the day was work on improving our collector more. We found that it had a lot of wobble because the CAD model had the wrong size holes for the bushing we were going to use. We ended up drilling out the holes for bearings and then packing them with a little bit of electrical tape to stop the wiggle. This fix will not be on the real robot but sometimes you have to do things like that to get your prototypes testable. There is still a very long list of variables that we don't have solved for our collector, here is just a sample.
  • Wheel type & diameter (we might move to a roller system instead of wheels)
  • Number of wheels and spacing
  • Speed
  • Angle to deploy down
  • Angle to hard stop the rotation in and out
There are plenty more too, all of this will get tested and iterated until we find the setup that collects best. We will probably keep changing some of these throughout the entire season.

Week 4 has come and gone and we're left with 17 days to build the competition robot and hopefully find answers to many of the variables in our robot.

- Spectrum

"An expert is a person who has made all the mistakes that can be made in a very narrow field." - Niels Bohr