Thursday, January 31, 2013

Day 26: Still Slow

With our parts delayed at the machine shops, we had another slow day. It looks like we won't be shooting discs with our practice bot till possibly week 6. We're behind schedule and it's starting to get a little scary. We're going to be cutting it close this year. Parts will be in tomorrow so we should be able to make solid progress on the practice bot tomorrow and Friday.

We started talking about our scouting team for competition that should be in place well before the events this year.

We'll have rookie team #4689 here from Royal High School to work out some programming issues and then this weekend will have 5 teams here for our Super Bowl Bumper Build. It's going to be fun having that many teams working at the same time, like a mini regional practice day.

Houston area teams, don't forget we are hosting the area scrimmage this year, Feb 16th, 17th, and 18th, in our gym. We're looking for naming suggestions as "the Houston Pre-Bag Scrimmage" is really boring. If you have field elements you are willing to donate to the event, please let us know.

- Spectrum

"Are you bored with life? Then throw yourself into some work you believe in with all your heart, live for it, die for it, and you will find happiness that you had thought could never be yours." - Dale Carnegie

Wednesday, January 30, 2013

Day 25: Slowing Down

We're waiting on parts and CADing, so there wasn't that much going on today. We are still trying to improve our stacking mechanism that will allow us to stack and unstack 4 discs easily. This is going to be very critical to our overall design.

The Chairman's team is very close to having a complete essay. We still have a lot of work to do on the presentation and the video.

Super Bowl Bumper Build
Spectrum will be hosting a Houston Area Bumper Build this Sunday. We should have several teams on hand to build their bumpers for the season. Send us an email if your team is interested in coming.

- Spectrum

"You can always amend a big plan, but you can never expand a little one. I don't believe in little plans. I believe in plans big enough to meet a situation which we can't possibly foresee now."
Harry S. Truman

Tuesday, January 29, 2013

Day 24: Batteries are finished

CAD is still progressing, and the first of the machined parts are being made at TX\RX Labs and Solarcraft Inc. We did a few cuts for the extrusion that will make up part of our superstructure, but mostly we're waiting on the machined pieces to get back.

We finished up our battery maintenance today.
We crimped and soldered every connection to all our batteries. We also labeled them with color names because we can. We shortened all our battery leads so we have less resistance in our electrical system. With a 6 CIM drive we want to keep all the power we can.

We need to find a new purple tape that works better than the duct tape. The duct tape leaves a residue. If anyone knows a good source for violet gaffers tape let us know.

We also had a CBA III donated to us by West Mountain Radio. This lets you easily analyze your batteries to see how they are performing. We're going to tack all of our batteries to better identify when they need to cycled out of competition use.

- Spectrum

“Be who you are and say what you feel, because those who mind don’t matter, and those who matter don’t mind.” - Dr. Seuss

Monday, January 28, 2013

Houston kit bot build day 2 & TX\RX Labs

Today we were on hand at the 2nd kit bot build day of the Ultimate Ascent season. We had a smaller turn out than expected, but we're opening our lab next weekend if teams are interested in more help.

After we wrapped up there, several of us went to TX\RX Labs to talk with them about helping us machine a few of the pieces for our robot. They originally tried to use their laser cutter, but instead will be cutting the parts on a CNC router table. TX\RX Labs is willing to help any Houston area team with their machining needs. We can't thank them enough for being so generous. 

- Spectrum

“There are three ways to ultimate success: The first way is to be kind. The second way is to be kind. The third way is to be kind.” - Fred Rogers

Sunday, January 27, 2013

HISD VEX League Day 2

Spectrum was on hand to help run the 2nd day of the HoustonISD VEX Robotics League. It's been great working with so many new robotics teams this year. We were the sole volunteer crew doing everything from reffing and queuing to running the scoring table and doing field reset. This is our 6th VEX tournament of the year, the last one will be March 2nd.

- Spectrum

"The greatest good you can do for another is not just to share your riches but to reveal to him his own." - Benjamin Disraeli

Friday, January 25, 2013

Day 21

That is the current CAD that we are finished with so far. All the electronic mounts have been sent to Solarcraft.

The rest of the robot is coming along; we're still working out the details of our strategy implementation and seeing how well this is going to work for us.

This weekend we will be volunteering around Houston, so no new developments on the robot. During week 4 we should be able to reveal the rest of the robot; some parts won't be 100% and will still need iterations but we will have a full CAD model to show.

- Spectrum

"It's kind of fun to do the impossible." - Walt Disney

Versaplanetary CIM/MiniCIM Mounting

Note: For more on this setup go to this CD thread (starts at about post #61). There might be ways to cut off less of the CIM shaft and still only use parts from a Versaplanetary gearbox.

It looks like the VEXpro Versaplanetary has a few more tricks up its sleeve. We didn't expect to find this, but it is a pretty simple conversion to install a CIM or a MiniCIM to the Versaplanetary gearboxes. JVN posted a small note that gave us the idea.

Disclaimer: These are not official directions, your mileage may vary. We haven't even put this under load yet, but it does spin up when you put power to the motor.

 Here is the complete assembly.

The Motor shaft has to be cut to just over a 1/4 inch. This leaves a very small amount of key, but it does seem to work. You could probably make a custom mount plate or double up the motor mounting plate to get slightly more key profile, but we were trying to do this with just one Versaplanetary kit.

 We have to cut a very small 2mm key to make this work.

The Versaplanetary motor mounting plate pilots the CIM motor face perfectly (THANK YOU VEX).
The input stage of the Versaplanetary has an 8mm hole with a 2mm keyway already to go (THANK YOU VEX). The hole is normally where the C-collar for the motor would go.

Assemble the motor into the gearbox input stage.

Using the 7/8 inch 8-32 screw mount the output stage of the gearbox to the CIM. You have to have the input stage off to get the bolt into the motor.

Remember to tighten the setscrew on the input stage.
Then mount the output shaft to the gearbox. Everything just sort of works (THANK YOU VEX).

There are probably better ways to do this, but this setup uses parts available solely from a single Versaplanetary kit and a small piece of 2mm keyway.

Day 20: 4700+ Views

Week three seems to be slipping away faster than the previous two. CADing takes a lot of time and we have to get parts laser cut very soon. We've been trying to work out as many of the details as we can so we won't have to make many radical changes after they are cut. The first parts should be going out tomorrow.

Today was mostly spent on batteries. We're going over all our old connections and soldering them and making the wire runs shorter. If you want to learn a lot about FRC electrical systems watch this video presentation by Al Skierkiewicz (Chief Robot Inspector). He goes over some of the techniques he has used on Wildstang (FRC#111) robots over the years, including three World Championship winning robots.

We're extremely pleased to have helped so many people during their prototyping. The shooter video has over 4,700 views. We have talked to teams from all around the FRC community (Minnesota, Arizona, Michigan, Israel, etc.) who are testing similar systems to the one we published 10 days ago, and they are having very good results. We are still improving our own implementation of the shooter, but we're excited to see so many others having success as well. Thank you all for the kind words and all the questions; they have helped us learn a lot about the system. Ideally, with smaller shooter packages teams can use the space it opens up to do some other cool things with their robots.

- Spectrum

"Cooperation is the thorough conviction that nobody can get there unless everybody gets there." ~Virginia Burden

Thursday, January 24, 2013

Day 19

We're still working on getting all our systems designed in CAD. We hadn't thought through several of them till today.

Here is the current CAD version of our "Can Opener" Hanging Device. This will see lots of changes before it ever even gets to the laser, but it's a descent start.

The flippers from yesterday are now mouse trap powered. This actually works much better than the surgical tubing.

We're not sure when we'll be able to start sending parts to the laser, but we're excited about how much prototyping we have been able to do. We think this will lead to a better final product.

- Spectrum

“The spirit, the will to win and the will to excel – these are the things that endure and these are the qualities that are so much more important than any of the events that occasion them.” - Vince Lombardi

Wednesday, January 23, 2013

Day 18: Details

Lately, most of the work has been in CAD, but we are still working on a few systems and details that aren't finished being prototyped yet.

Here is a picture of the prototype wings that we are planning to have fold out from under our bumpers to make sure discs only go under our robot and not under our wheels. We're still looking for an elegant way to do this, but we're confident we can find one in the next few days.

We have to get a lot done over the next three days because this weekend we won't have much time for the robot. On Saturday we are volunteering at the HoustonISD VEX League and on Sunday we are supporting the 2nd day of the Houston Kit Bot Build Days. Both events are important to the Houston robotics community but they also take time out of our build schedule. We just have to work harder during the time we do spend in the lab.

- Spectrum

“The great thing about working hard is that you can always work harder, the great thing about being good is that you can always be better.” -- John V-Neun

Tuesday, January 22, 2013

Day 17: Starting to CAD

Nothing spectacular to show yet. We still have some things we haven't published on the blog that are integral to our strategy this year. Hopefully, in the next few weeks we will know for sure that they all work and we can publish them.
We've started the CADing process. Here is the start of a simple belly pan for the robot. It's going to get lots of holes for wires and electronics mounting.

We're working on the CAD for our shooter, collector, and other systems as well.

One of the items we prototyped today were wings that fold out from the side of the robot under the bumpers to push frisbees towards our collector. That way if we hit a disc with any part of the front of our robot, it will hopefully be collected by our intake. The goal right now is for these to be spring actuated and deploy as soon as we move during autonomous mode.

We're also working on a pop up version of the "Can Opener" Hanging device. That way we can still drive under the pyramid during most of the match and then pop it up right before the end and hang quickly for 10 points.

- Spectrum

"Great discoveries and improvements invariably involve the cooperation of many minds. I may be given credit for having blazed the trail, but when I look at the subsequent developments I feel the credit is due to others rather than to myself." - Alexander Graham Bell

Monday, January 21, 2013

Day 16

Into week three and we're charging ahead.

We briefly tried prototyping a floor pickup mechanism that shot the discs up a ramp to the top of a tall robot. We think the idea has merit but we would need to do a lot more prototyping before it's ready for the field. If any other teams want to take the idea and run with it, feel free. We think it would be a great way to have a really fast pickup mechanism.

This morning we went and picked up a piece of official FIRST carpet from our friends the Discobots. They got it after the 2011 Lone Star Regional and haven't been using all of it so they gave us half. It was quite the adventure getting it to the third floor of the school but we managed.

Over the next week and half we're hoping to have finished CAD models of the robot to send to the laser cutter. We're trying to prototype all of our system completely before make the runs on the CNC machine. That way, we can be more confident about our designs and specifications and make fewer changes to the laser cut pieces.

We did a weight estimate and it looks like we are going to be way underweight with our current systems (< 100lbs). If we get everything done well, we may be going for a 30 point climb before our second event. We are saving room at the back of our robot and with around 20lbs to play with we should be able to come up with something. These smaller chassis dimensions make your whole robot lighter, plus VEXpro aluminum shafts, gears, and sprockets help as well.

- Spectrum

"There are no secrets to success. It is the result of preparation, hard work, and learning from failure." - Colin Powell

Sunday, January 20, 2013

Versaplanetary 1:1 Conversion

1/23/13 Edit: VEX has released the Versaplanetary User Manual please look over this before following these instructions.

We have received a lot of questions about our 1:1 Versaplanetary conversion. It really is a simple process, but we thought we would post some pictures to help teams out.

Disclaimer: We don't work with and are not sponsored by VEX Robotics. None of this should be taken as official recommendations by VEX or Innovation FIRST Inc. So far this has worked for us; your mileage may vary.

1. Purchase at Versaplanetary 10:1 gearbox (this does work with the other models, please see this post by Paul Copioli for more information).

(Note: A normal 10:1 has a 1/2" Hex output shaft.  We are currently using it on our 3:1 so it's pictured with the 8mm output shaft; they work the same)

2. Unscrew the two 10-32 screws from the front of the gearbox and remove the output stage and the middle stage with the gears.

Break down of a planetary Gearbox.

Sun Gear with male spline on the back
Ring Gear
Planet Gear
Planet Carrier

 3. Note the splines on the output shaft and on the ring gear are the same.

4. The motor input stage has a female spline that matches the output spline and the sun gear.

5. Put away all the middle stage gears. You don't need them for this, but keep it around because you now have a 10:1 stage to add to other Versaplanetary Gearboxes to make them a bigger reduction.

6. Mount the input stage to the output stage. Make sure the small little pins are aligned so all the bolts will align.

7. Now you have a 1:1 reduction. Pictured is a 1:1 reduction with a BB550 motor, so that the output shaft's free speed would be around 19,000RPM.

For instructions on mounting motors to the gearboxes please go to the VEXpro quick start guide.

- Spectrum

"Ideas come from everything” - Alfred Hitchcock

Day 15: Houston Mini Maker Faire

We took the day off from constructing our 2013 robot to take Violet out to the Houston Mini Maker Faire. It was a fun event that drew a lot interest. We were able to show FRC and VEX to over 2,500 people. It was also the first time we were able to distribute our new Elementary Engineering activity book that we designed for small children.

- Spectrum

“The things you do for yourself are gone when you are gone, but the things you do for others remain as your legacy.” - Kalu Ndukwe Kalu

Saturday, January 19, 2013

Day 14: Two weeks down four to go

Our current plan is to build a (mostly) functional prototype robot before we send off parts to the laser cutter. So many of the pieces have a lot of features jammed into them that we will need to work with them physically before we are confident enough to have them laser cut.

The VEXpro drive train is now riveted with 1/4" steel rivets. We want to be extra sure our chassis won't come apart. Here are a lot of pictures of our modifications to the chassis. We now have a full 15.5 inches between the wheel wells because we moved to a single loop of chain and the versawheels. We will be mounting CIMs #5 and #6 in the future.

The other systems are coming along, although a bit slowly. We're hoping to have something to mount on top of this in the near future.

- Spectrum

"I am looking for a lot of men who have an infinite capacity to not know what can’t be done." - Henry Ford

Friday, January 18, 2013

Day 13: Drive Train Testing

We're close to two weeks in and we finally have a moving drive train (with test electronics).  We're using the VEXpro Drive in a Day Chassis. So far we really like this version of a kit chassis. It's customizable and very well suited for the new size requirements. It was specially designed for Ultimate Ascent and we think it's going to play the game very nicely.

The current setup is as follows: (This may change as we tweak things)
The chain is a single loop so that we can compress our wheel wells down to only 2" in width. This gives us back some of the room in the interior of our robot that we lost with the new size restrictions. The electronics board is just a test panel that we have in the shop. The real electronics will be crammed in the chassis and around all the mechanisms. We're trying to find ways to make this robot easier to work on because it's going to be cramped.

We have noticed its very loud but we think a lot of that is due to the tensioners that we are using.

Here's a short clip of our brief test drive.

We still don't have all the features for the systems that go on top of the chassis, but we are getting closer.

- Spectrum

“You'll never get ahead of anyone as long as you try to get even with him.” -  Lou Holtz

Thursday, January 17, 2013

Day 12: Drive train is on the ground

We finished the VEXpro drive train, as we were wrapping up for the night. So no video tonight, but we should have some test driving videos tomorrow. We're pleased with some of the modification decision we made and they seem to be working out so far. We had to do some minor adjustments to fix a few things, like a broken bearing in a gearbox, but other than that it looks good.

Shooter development continued for another day. We moved to two BAG motors and played with a lot of wheel combinations. We don't think the type of Banebots wheels do that much to distance so we are planning to use the blue ones, hardest of the 3 types, so that they last longer.

We're still working on our collection system and our feeder mechanism to move discs into the shooter wheels. These will both be critical to the success of our design.

CADing is now our main priority as we need to get drawings to our sponsors, sooner rather than later. Practice time is going to be as important this year as ever and we also want to spend a lot of time on our autonomous development as well.

Here is another shooter prototype video to hold people over.

- Spectrum

"It is literally true that you can succeed best and quickest by helping others to succeed." - Napoleon Hill

Wednesday, January 16, 2013

Day 11: Ultimate Ascent Shooter Testing

Our shooter works! After 10 days of prototyping we are making very nice shots from about 15-17 feet away from the goals. We still have a lot of optimization to do but so far we are very happy with the results.
Several team members spent the better part of the last two days making the goals for us and they did a great job.

Full Specs on this implementation:

This is running at full speed. We believe that if we play with the motor combinations we can reduce slippage and get much more distance from this two wheeled setup.

The great thing about this shooter is it can fit in to any design because it's so small. You barely need more room than a disc. It's also pretty inexpensive. The versaplanetaries are the most expensive part and you could probably replace one of them with a CIM or MiniCIM to make it cheaper.

We kept putting together the VEX pro chassis, there were a few more things we didn't have that we needed. We will continue working on it till we have it driving. Hopefully it will be tomorrow.

We also noticed the new rule change to G23; this changes everything for a lot of teams. Doing this so late is very frustrating but hopefully the GDC (game design committee) will figure out a way to prevent changes such as this in the future. We think we are in a good place with or without the rule change so we are going to keep on moving with our current design path.

We're planning a Bumper Build day at our shop for Feb 2nd or 3rd. Email us if you're interested in coming and making bumpers with us. We'll provide the pool noodles and wood, you just bring some fabric and we can have a lot of teams squared away before the regionals.

- Spectrum

“The habit of doing more than is necessary can only be earned through practice. And the habit is priceless.” - Seth Godin

Tuesday, January 15, 2013

Day 10: Chassis Construction

We received our VEXpro chassis today and various other parts from VEX Robotics. This new line of off-the-shelf parts has been extremely useful this year.

We should have sprockets and wheels tomorrow and be able to do our first test drive. We are modifying the design pretty heavily to give us more room between the wheel wells. With the new size restrictions we have to be much more conscious about space.

Shooter development made huge progress today. We got in more Banebots wheels and now we have a very effective and compact two wheel shooter. This setup was able to shoot discs about 25 feet and this is by no means optimized. We're hoping to have a 40+ foot max distance in case we need to feed another shooter. We're using two Versaplanetary gearboxes. One is setup 10:1 with the BB550 motor and the orange wheels. The other is a BAG motor at 1:1 with the green wheels. We think the bag motor is still slipping so we may reduce it to 3:1. Hopefully we will be testing a bunch of motor/wheel/gear ratio combinations till we find the best solution. We really like how compact this shooter is.

We still have a few systems that really need development but the overall plan for the robot is coming together very nicely. Hopefully will have our first parts sent off to the laser cutter this week.

We constructed PVC goals today in the small space we have for field elements in our school. Soon we'll have a full pyramid as well, though, since climbing has been shelved for a bit, we're not in too much of a hurry.

- Spectrum

"When given a choice, choose the thing that scares you a little. If it's 100% safe, it is holding you back." - Jeff Atwood

Sunday, January 13, 2013

Day 9: First Kit Bot Build Day

Today was the first of two Houston Area Kit Bot Build Days. Spectrum brought 15 people to the event to help teams, put together their kit chassis, and assemble their electronics. We were happy to see many of the teams that participated in our Mock Kickoff back in December. We love being able to help teams get their first taste of FRC. We'll have another kit bot build day on the 27th, and if needed we might do a bumper build the morning of Feb 3rd.

We still have a lot of little details to work out with our design but overall things look promising. This week will mostly be dedicated to CAD and putting together our drive train. We should have our VEXpro chassis tomorrow.

- Spectrum

“Competition is very rarely as useful as cooperation. Our society is geared toward competition — rip each other’s throats out, survival of the fittest, yada yada. But humans are meant to work together for the survival of the tribe, and cooperation pools our resources and allows everyone to contribute what they can. It requires a whole other set of people skills to work cooperatively, but it’s well worth the effort.” - Leo Babauta