Shields Up!

In light of our recent acquisition of sponsors – as well as the need to display our team number – we plan to construct a frame for our robot, where we'll mount two big sheets of plexiglass. This serves two ever-useful functions: first, it gives us a place to put our sponsor(s) logo(s); second, it gives us a shield to prevent other robots from damaging our robot's insides; third, now we can put Sonic on Sonic. As a side effect, we also now have a place to put the brain and battery where there easily accessible; I took the liberty of drawing that up in SolidWorks too. 

Autonomous Ring

In the interest of speed and efficiency, we decided to create a separate holder for the autonomous ring.  This holder allows three things to be accomplished: simpler coding, placement of the ring, and ideal positioning.  The slight advantage this gives may not seem like much, but it adds up.

Improving the End Effector

The old end effector design, while good, was not as efficient as we wanted – it worked beautifully, but being the perfectionists that we are, we wanted to do even better.  We decided to slightly alter the shape of the end effector, which should allow it to secure the rings even better. It is still a prototype, but the results so far have been promising.

Casey's New Toy

Today, we finally got the shipment of IR Sensors that we'd been waiting for, and the team is rightfully excited. Unfortunately, the only thing standing in the way of Casey and his new toy was the mandatory prototyping we do before sticking it on. So in lieu of being hounded to death by the general populace, I quickly drew us a simple mount for the sensor. It's not pretty,  but it gets Casey off my case and onto the computer, so I call that a win!

The Finger Muncher Mk. II

Our lift system for the arm worked beautifully, but we soon realized that we had not allowed enough room in the upper portion of the tower for the arm, which ultimately resulted in the tower and axle getting warped.  As our arm had screws and brushing on it, it was actually wider than the gap provided by the two support channels, making them bend apart and bend our axle. We began brainstorming on methods of preventing this, such as supporting the channels to prevent bending or moving each channel a spot over.  We finally decided on using two supports connected to a single support with flat brackets in the middle, which provided a sufficient enough space to allow the arm full rotation without any bending.  At the same time we edited the lift system and moved the spool outward to allow for easier access and maintenance.  The result is the Finger Muncher Mk. II – a beautifully efficient arm and lift system that will happily devour any finger that gets a little too close to it.

Base Instincts

As the channel the motors are mounted on would bend while moving the lift up or down, we attached a second channel next to it that mounts one channel to another, preventing bending or rotation. This makes the motor mounts much stronger and gives the axle less give to slide.

Weekend Recon

Casey, Travis, and I took a road trip up to Tampa in order to watch the FTC competition at Hillsborough Senior High School, as we have several new members and wanted to become familiar with the event before its our turn to compete.

Coming Together

For the first time in a long while, Sonic is once again ready for testing. We fixed the string system for raising and lowering the lift and moved it so it is easily accessible if it needs to be changed or repaired. While practising with the robot, we noticed that the axle holding the strings would slide, allowing the gears to lose contact with each other. By providing more stabilization to the motor mounts and adjusting the axle, we hope to prevent this from occurring.

String Theory

What is touchy, fragile, and impossible to maintain? Our string spool, apparently. Whenever our robot decides to break its string – which it does more often then we'd like – it becomes a full day's chore to replace it. A few cramped hands later, we decided we needed a new one. So, as usual, it's back to SolidWorks for prototyping. The new one will move the whole spool assembly out to the back of the robot, making it a lot more accessible and – hopefully – easier to repair.

Repositioning

In a unanimous vote, we have decided that our current placement of the motor controllers is ridiculous and silly; as such, I have endeavored to devise a new, improved strategy for attaching them, involving one plexiglass sheet, some screws and – by popular vote – some velcro. It should do several things: make the wires neater and more accessible  provide additional support for the arm, and allow for there to be velcro on the robot. All is right with the world.

One String to Rule Them All

After no school on Monday, we reconvened today to finally finish up our string system, only to instead attempt to use one string for the whole system, creating a whole new set of problems to solve. The strings would slip on the axle, so we had to tie it through the collar in the middle of the axle. After getting everything strung and ready for testing, we found that a single string would spool too much and become tangled, making all our work pointless. Back to our original two string idea...

Switch 'Em Out

While the old end-effecter was fairly decent, any room for improvement must be seized. We drew up a SolidWorks for a new ring grabber, and it looks promising. Construction starts Monday. 

Working for the Weekend

Casey, Travis, and I stayed very late after school today to continue working on the lift system for our robot. The string system Nik worked up earlier became tangled after a couple of uses, rendering it useless. Primarily we need to work on keeping it untangled and making sure it can lift the slide.

In a Bind

Stringing the robot has proved a much more daunting task than previously believed. Travis built a string separator out of plastic and I reconstructed the assembly, only for my knots to come undone. Casey then attempted it a second time with the exact opposite outcome of knotting it too well and rendering it completely immobile. In response I've researched methods of tying knots and have hopefully solved the problem for Monday, as its too late to get anything else done today.

Feeling Rather Spoolish

Apparently, the spooling system we have now isn't quite working as expected; it has a tendency to fray the string. So, I went off to SolidWorks to draw up a concept for a new one.  Unlike the last spool – which was mounted on the side – this one goes between the two bars in the arm, meaning that it's a more direct route for the string than before. In addition, the string uses the arm's axle as a pivot, meaning it will always be the correct length regardless of what angle the arm is at. Pretty nifty, I think.

Silly String

 Nik and Pierce troubleshooted our lift system and decided to scrap the string being wound on the side, as it would not wind correctly and started to destroy the string. Instead, the string was moved to an axle beneath the arm that is turned by a gear attached to a motor. This arrangement prevents the string from stretching when the arm is lowered- another problem we encountered- and provides more torque for raising the lift, making it a much better solution. 

30 Minutes or Less

The parts that we ordered finally arrived today, greatly increasing the resources that we have at our disposal and allowing us to build bigger and better robots. These new parts will be stronger that the parts we currently are using and will provide us with better performance. 

Decoding

Casey took the time to fully comment his program for the robot and improve the readability of it thanks to the presentation we viewed last Saturday at St. Thomas. The code will now be much easier to edit by Casey and the rest of the team if we need to make changes to improve performance.

Going Up

I attached the slide to the arm on Monday and today Travis and Casey attached a motor and string to the robot  so that the slide would be operational. The decided on attaching the motor near the base of the robot to improve weight distribution and have the string feed through the channels to the slide so it wouldn't get caught or damaged.

Chutes and ladders

We acquired a drawer slide for Sonic. We plan to use this slide to reach the third and final level of the rack, thereby completing the arm of our robot. The first major challenge is deciding where to place the slide on the robot, balancing stability and functionality. We decided to initially attach it to the top of the arm and proceed from there, moving the arm if it proves too unstable. In the future we will need to drill additional holes in the slide to attach it firmly, but this arrangement seems promising.

Proving Grounds

Today is our practise tournament at St. Thomas High School where we can meet other teams and test our robot against theirs in the ring. We can also create friendships and alliances here that will follow us long past this year's FTC challenge, making this a great day for our robot and our team.

Schedule

FTC Programming Workshop

The St. Thomas team presented a power point on the basics of Robot C. They discussed Robot C tools and the  programming language, as well as an efficient way to code the robot using comments and functions to clean up and improve the readability.

FTC Engineering Notebook

Cypress Bay High School Did a presentation on the Engineering Notebook and what they did to win the Think award for their notebook from the previous competition. Aspects we learned to add to our notebook are more specific figures about our engineering process and the challenges we face daily.

News of the World #2

What Really Grinds My Gears...

The arm design we used to reach the second level of the rack had a gear ratio of 25 to 1 in order to provide the power we needed to reach the height with the weight of the grabber. An unfortunate side effect of this gear ratio is the large amounts of stress it puts the parts under. We experienced this first hand when the axle our arm was on was twisted and bent by the force, forcing us to cut it in order to replace it with a new axle that can better handle the stresses.

Mentorship

Casey went to Western High School to help mentor the rookie team that visited us the other day after school.

Here It Goes Again

Casey and I stayed afterschool today to practise with the robot and our new arm as we have a practise tournament on Saturday, November 3. This is one of our runs, timed at a two-minute period. After repeated practise we got our best to be 12 rings placed on the middle rack, and developed a strategy to get the most rings in the least amount of time.

Not another brick in the wall

Today, we were visited afterschool by Western High School's FTC rookie team. We showed them our set-up and gave them valuable knowledge about designs and coding. Our team really hit it off with their group and we exchanged contact information in order to provide further assistance to our hopefully future competitors.

Armageddon

The arm is now finished and ready for testing. This arm needs to be able to grab rings from the first level and deposit them onto the second level of the rack, all while maintaining balance and structural integrity. The arm can move up and down and the grabber on the end can rotate, giving us the degrees of movement we need in order to place the rings.

Growth Spurt

We removed the previously short aluminium channel and replaced it with a longer channel that can reach the middle level of the rack. In order to do this, we had to remove our cross support and brain mount, meaning we'll have to find a new location for them. Additionally, we will have to add an additional motor to the channel that will enable the grabber to rotate to grab and release rings.

Burn Out

While practicing today, our arm got caught on a rack and one of our servos burned out. Now we need to either replace the gears or the servo. While this is an easy fix, it serves as a reminder that parts are fragile and that our build needs to not only accomplish the task but prevent the parts from being damaged or over exerted.

Trust me, I'm a Doctor

Slight modification to our grabber to improve grip, we attached surgical hose to the Lego pieces to improve friction. This prevents the rings from slipping out of the grabber, making it easier for us to move the rings to the rack and score points.

Arms Race

Today our working design is due; it must be coded and be able to pick up a ring. Our grabber design is finished, so now its just a race against the clock to get an arm working so that our grabber can actually reach the rings.