Day 8: Prototyping and Miscellaneous

by Christian and Michael Simeon

Catcher Prototype

Today, students lined the catching prototype with VEX field flooring tiles to help keep balls in the catcher by preventing them from bouncing off the PVC pipes and rope. Students also improved on the attached intake prototype. Additionally, they attached gyroscopes and encoders to allow the prototype to better recognize angles and ultimately better function. Students have begun testing for those encoders and gyroscopes added to the drive base. Sending data from the encoders and gyroscopes to a web browser with graphs and statistics on the robot will help with fine tuning the prototype.

The Shooter Prototype

An elevator system with metal bars and PVC has been added so that balls can be more consistently fed into the shooter. Additionally, the arch on the top of the shooter prototype has been modified. Later, metal and PVC were removed and replaced with a frisbee and cables.

CAD

Today the people working on CAD continued working on drive base. They mirrored the gear box for the other side of the robot and added it to the drive base CAD. They also added the electronics and other necessary components. Finally, they also made part drawings for spacers in the gear box.

Team members also continued thinking about packaging options for the superstructure. We have decided on having three pivoting arms for the robot’s two intakes and catching hood. All arms will be piston-actuated and are designed to fit within the 20″ extension rule. The intakes are bent to allow for rollers to contact balls as the robot spins to grab a ball. With straight bar intakes, the bars could push balls out of the way of the intakes.

We also discussed mechanisms for locking the hood in place during shots to prevent the balls from pushing against air pressure to reduce hood compression. Discussed mechanisms included an over-center piston linkage and a locking piston mechanism. We will likely move forward with the locking piston mechanism.

Miscellaneous

Students and mentors worked on the lathe to create standoffs for the gear box. Additionally, work continued on submissions for the Entrepreneurship, Chairman’s, and Media and Technology Innovation Awards.

Action Items

• Finalize entire drive train design and CAD with mentors to prepare for ordering the baseplate
• Finalize catcher prototype with Abhi
• Finalize control board design with Brandon Gonzalez, Chris Sides, and Abhi Kumar
• Work on pit display with Travis
• Brainstorm ideas for publicity releases for team social media sites for releases throughout the build season: for Jeremy, but he will not be there
• Create and maintain a Gantt chart for Mani
• Help Mani clean up
• Ask a leader for other tasks on the Trello

Day 7: Prototyping, CAD, Testing, & Lab Improvements

Catcher & Intake Prototype

Today, several team members integrated the intake and catcher prototypes with the 2013 practice robot drive base to create a prototype robot that can catch and intake the balls. They removed the catcher arms from the back and front of the drive base and placed the intake in the back of the drive base. Additional planks of wood were attached to the walls of the intake to increase the compression on the ball while from the intake.

Several students began working on a new intake roller prototype. This new mechanism uses 1.5″ neoprene rubber rollers instead of the current 3.5″ blue bane’s bots wheels that are currently being used.

Shooter Prototype

A group of team members worked on further tuning the shooter prototype. They also performed several tests using different shooting angles and different distances from the goal in order to determine the optimum shooting distance.

Additionally, we began to improve the shooter prototype by adding reinforcements to the base and machining a new hood.

Prototype Testing

The groups working on the shooter and the integrated catcher and intake prototype came together to test whether or not it is possible for us to shoot over the truss using the current design. The conclusion is that the design will work, but it needs further tuning to be consistent. This test was done by using a “dummy truss,” also known as EJ.

The same group also tested whether or not it is possible for another robot to catch the ball as it is being thrown over the truss. The special constraint that we tested was whether or not the catching robot could start at the same position as the throwing robot and be able to drive fast enough to catch the ball. Although this robot has the same ratios as we are planning on using for the 2014 robot, it lacks a superstructure and is lighter, resulting in superior acceleration.

CAD

Work continued on the design of the drivebase for the robot. Right now the drive base is functionally identical to the previous year’s drive base. The only major changes have been the mounting points for the superstructure, which have been moved closer to the bumper mount to allow for a superstructure wide enough to hold the large balls in this game.

The team also got together to design the look of the rest of the robot. They discussed how to integrate the two intakes, the shooter, and the catcher into the robot and the overall design of superstructure. Right now there is a rough idea of how the robot should look. Further detailing will be based on the results of prototyping.

Lab Improvements

Today, we also worked on installing better light fixtures over the metals fabrication area in the lab. This will improve the lighting of the area, which will also improve machine quality and safety.

Manufacturing

The center bearing housings for the drive base were finished and polished today. As a result the manufacture of additional parts will begin.

Action Items

• Continue testing shooter prototype
• Finish manufacturing new intake prototype
• Finish drive base CAD
• Send baseplate for manufacturing
• Continue designing rest of the robot
• Begin manufacturing parts for the drive base

Day 6: Prototyping the Catcher, Building a New and Improved Flywheel, and Organizing Parts

by Jeffrey Kaufmann

New Flywheel Prototype

A team of students worked on the updated prototype of the flywheel shooter. The new prototype can shoot at an almost vertical angle, enabling the robot to toss the ball over the truss. It also allows for easier packing because its flywheel is smaller than that of the first prototype yet still retains the positives aspects of the original. Some problems occurred during the construction of the new wheel such as broken or splitting wood pieces delaying completion.

This piece had to be replaced. The team attached the curved piece of the flywheel that allows for an approximately 45 degree trajectory.

New Catcher Prototype

A group of students worked on fixing the second catcher prototype. This update will allow for a more mechanically robust device. The rope on the catcher and add a few metal pieces were overhauled today, resulting in a tighter, more stable and cleaner design.

After testing the new mechanism while driving the results were quite satisfactory. The great mobility of the drive granted the ability to quickly get underneath the ball and receive an almost perfect catch.

Programming

The programming team worked hard on the coding on day #6. Today they made it so that the robot can now serve HTML pages. Furthermore, they had to refactor some of the code. In conclusion, while they had to restructure the code, this change did not affect how the code behaved.

Organization of New Equipment

Recently, we received new equipment for the lab, such as soldering devices and other tools. Several students helped organize these new parts and categorized everything received into an Excel document, creating in effect an organized system of all the new equipment within a neat document.

Action Items

• Continue helping Abhi and Dan with catcher prototype and an add intake system.
• Continue helping Ahmed and Paul with shooter prototype improvements
• Continue testing
• Continue working on the drive base CAD with Andrew

Day 5: More Prototyping and Gearbox CAD

Flywheel Shooter Prototype

Today, we continued work on a new flywheel shooter prototype. The team determined that smaller shooter wheels would make the shooter more packagable in the robot. We made some great progress and we should be able to complete it tomorrow.

Design

Work continued on the drive gearboxes today. Based on the results of the simulation discussed yesterday, we decided that we would move forward with 2 3 CIM motor gearboxes but would also design 2 CIM motor gearboxes that could be swapped in if necessary. Although this would reduce acceleration, it could lighten the robot by up to 8 lbs.Today, we added the Bimba pancake pistons to the two speed gearbox assembly. We are moving forward with the previously discussed ratios of 4.2:1, 19.6ft/s in high gear and 10.6:1, 7.6ft/s in low gear. The CAD is almost done and is only missing a few components.

Programming

Today the programmers continued work on the graphing system for the robot. They worked on getting a TCP/IP server running on the robot and working out the technicalities of using a browser to monitor the stream of data from the robot.

Action Items

Finish Gearbox CAD, begin finalizing Drive base CAD

Day 4: Prototypes, Coding, Drive base design

Catcher Prototype

Today, we continued work on the catcher prototype, making it higher and wider so that it can better catch balls from all angles. Although the catcher is promising, its large size may be a problem when packaging mechanisms for the robot.

Catapult Prototype

The catapult prototype was finished today. The shooter is very smooth and can be easily reloaded in less than 5 seconds. It is consistent and accurate from up close (~2 ft from high goal) but mediocre from midway to the white zone. This shooter suffers from inconsistency in ball positioning within the catapult which could be improved with a better ball cradle.

Flywheel Shooter Prototype

The flywheel shooter has been the most successful thus far with accuracy, precision, range, and simplicity. Because of its success (especially in scoring all 3 balls in under 5 seconds), we took it apart to replace the large wheels with smaller wheels while narrowing it to maintain ball compression with the smaller wheels. We hope to test this tomorrow.

Programming

Today, the programming team worked to get the 2013 practice robot up and running to test the drivebase. Several problems were encountered along the way. First, they had an SDK error on the robot which took them a long time to fix – eventually a cRio reflash solved the problem. Second, there was a problem with the wiring on the robot so they weren’t receiving any data from the TCP server. They eventually fixed the problem and now they are working on a way to graph the data from the robot in a quick and easily readable way.

Over the next few days they will also work on are prototyping some autonomous for the robot as we determined the autonomous is very important strategically.

Autonomous Strategy

We have determined that the autonomous period is critical to our success in Aerial Assist, allowing the robot to score up to 65 points. Because of this, we want our robot to be able to score 3 balls in under 5 seconds. The flywheel prototype is the most promising for meeting this objective.

Over the next few days, the programming team plans to start working on drivebase control loops for autonomous, using Overkill as a practice base.

Drivebase Design

Today, work began on the robot drivebase, taking heavy inspiration from last year’s robot. The robot’s 6WD drivebase is the same overall size (28″ W x 27.75″ L) with wheel wells that can accommodate up to 1.5″ tread width. Today, we created a rough chassis in CAD and started work on the 2 speed drive gearbox.

The planned drive speeds are similar to last year (3 CIM motors per gearbox, 12:40 inital reduction, 15:48 low gear reduction, 28:38 high gear reduction, 3.5″ wheel diameter, 19.6 ft/s & 7.7 ft/s theoretical speeds). Due to the tight clearance between the 40T gear and the dog, the outer diameter of the dog will need to be reduced somewhat. Overall, this is a very similar gearbox to last year.

To determine the acceleration performance of our planned ratios, we performed a simulation of the drivebase accelerating. We decided to optimize the robot for 10-15 foot sprints and found that the ratios worked well with these goals. Furthermore, we found that while the 6 CIM drivetrain could reach 10 or 15 feet 10-20% faster than the 4 motor drivetrain, it drew much more power and could lead to premature battery drain.

Action Items

• Test flywheel shooter prototype.
• Test intake prototype with Mani.
• Continue working on drive base and gearbox design with Nagy.
• Compare all 3 shooter prototypes and decide on which we want to use.
• Continue work on drive code and autonomous planning with Stephen and Brandon.

Day 3: Prototyping continued, Autonomous strategies, and more

Autonomous Strategy

Today, we discussed scoring all three balls in autonomous. In autonomous, only the area directly in front of the low goal is guaranteed to be undefended. The strategy would involve starting with one ball in the robot, one in front and one behind. The robot would immediately drop an intake on each side of the robot and drive to the hot goal to score, dragging the balls with it. We also discovered that a banner sensor was able to pick up the reflective tape, meaning that the robot wouldn’t need to a camera to detect the hot zones.

We discussed whether it was more beneficial to shoot from afar or really close to the goal. Several team members proposed that shooting 2-4 feet away would be best since it would more than likely increase the robot’s accuracy. The fly wheel shooter was set up about 3-4 feet away from the goal and was able to successfully score

Catapult Prototype

A group today worked on a catapult prototype. A good amount of progress was made and it seems to be coming along well. The only things left to add are the rope, springs and hard stops.

Ball Catcher

Some of the students worked on a basic catcher prototype, making it from PVC pipe. They added a funnel to the top to increase the likelihood of the ball going in. It worked out well with some minor strengthening.

Programming

The programming team worked on a basic autonomous runner that uses threading. In essence, it allows for commands to be run while still allowing evaluation to occur. Also, in the event that a command should fail or timeout, the robot will skip the rest of the commands. One of the ideas that was brought up was separate compilation for the main code and autonomous routine to allow for quick changes to the autonomous without having to recompile the whole codebase.

Day 2: Prototyping, Drive base Design, Initial Coding

Prototyping Shooters

Three different teams worked to design, build, and test three different ways to launch the ball. They built a catapult, a linear launcher, and a flywheel shooter.

Catapult Launcher

A catapult was designed and built today using a system similar to other catapults we’ve seen for this year and 2008. This quick prototype was not strong enough to launch balls far enough and the team needs to improve the design tomorrow perhaps by making it more stable and utilizing another tension device such as surgical tubing.

Linear “Trident” Launcher

Flywheel Shooter

The flywheel shooter was completed today, and students and mentors began testing with it. Of the three shooter prototypes, the flywheel had the best shots and most consistency. Additionally, the team could test the effects of ball pressure on the consistency and accuracy of shots for the first time in the season. By the end of the night the flywheel shooter made about 1/3 to 1/2 of its shots.

Programming

The programmers met today and decided on what they wanted to work on for the next few weeks.

It was decided that we would like to spend time building debugging tools for the robot. The main thing that needs to be built is a way to live graph motor and sensor states, much like the PID tuner we had in 2012.

The programmers also decided to rework how autonomous mode will be executed so that control flow can be used in autonomous rather than just a straight sequence of events.

Tom and Stephen started a new Java project for the 2014 robot and got basic CheesyDrive working on the 2013 practice drivebase. This code will use a new subsystem architecture and will use very little code provided by WPI.

Field Assembly

The team completed the construction and mounting of one full set of high goals. The goals have a ramp designed to return the balls back onto the field so that they do not fall onto drivers. We will use these wooden goals while we wait for the official set to come in from FIRST.

Drive Base Design

Today, the team began modeling parts for the gearboxes and chassis. We plan to design a drive base similar to last year but without a PTO on the gearbox. Tonight, we designed the gearbox output shafts, intermediate shafts and wheel shafts which will be sent out to sponsor Modern Machine Company tomorrow.

Action Items

• Continue gearbox design
• Continue testing and improving flywheel prototype.
• Continue testing puncher prototype, try to increase power.
• Rebuild catapult prototype, must be stronger and more stable.
• Programmers continue improving drive code and autonomous tuning with Tom.
• Improve catcher prototype with Dan.
• Possibly begin machining parts for the drive base.

Day 1: Kickoff and Game Analysis

Kickoff Overview

Today kicks off the 2014 FRC Season for Team 254. The mentors and students are equally ecstatic for this year’s challenge, Aerial Assist.

Google Drive PDF of the Game Manual:
https://drive.google.com/file/d/0B_TTQ23_FVkAWjM0cjBsbUw1TkU/edit?usp=sharing

Game Animation:

Team Kickoff

Today a group of students attended the 6:30 to 9:30 local San Jose kickoff at Morris Dailey Auditorium. A few others watched the NASA Live Stream from home. Subsequently, at 10, the team met for the team’s kickoff event and discussed the plan for the coming six-week build season. The team then broke up into groups and discussed strategies in terms of necessary robot qualities, priority tasks, and possible scores. The parents and mentors simultaneously discussed logistics and the build plan in more detail until the student leaders returned to present their ideas to the entire group.

Game Analysis

After lunch, about 70 students congregated in the Bellarmine Robotics Lab to examine and better understand the team rules. In particular, they discussed the definitions of assist and possession and clarified the rules for such actions and others on the playing field. For the first two and a half hours, the group went through the relevant sections of the game manual and encouraged group discussion to find possible holes and list them to check with FIRST later. The group noticed some deviations in rules from previous years: the field is two feet narrower at 25 feet, and the match is 30 seconds longer. The autonomous period is five seconds shorter at 10 seconds, and the tele-operated period is 35 seconds longer at 2:20. Andrew Torrance noted the possible issues with battery life with the 25% longer match time. In addition to discussing rules, the team also formulated questions concerning the regulations to ask FIRST:

• Can teams do assists in autonomous?
• Can teams hold balls in autonomous to do an assist later?
• Can a team throw over the truss again to try and get a catch, say, if an alliance earns a successful truss score, but does not successfully catch. Can the alliance try for a second chance? In other words, while the group recognizes that only one truss score counts per cycle, do the truss score and the associated catch score have to be earned on the first attempt?
• Do teams get points (ex. throwing and catching in the end game) immediately, or do the teams only get them once the cycle completes? This is related to the question of assisting in autonomous. Possible answer: Maybe not because autonomous shots are not cycles.
• Teams need clarification on which goalie zone to which the initial position regulations refer. In which goalie zone do teams start if they do not want to start in the white zone? Can human players help in the middle of assists?
• Can human players catch truss scores to make them legal?
• Teams need a better definition of possession for robots in general. For example, for a trough-like robot, is holding the ball as it rolls considered possession? What time period differentiates harmless “deflection” from “possession” of the opponent game object (which earns a severe technical foul penalty)

After a short break, the team’s new mentor Jared set up a Google Spreadsheet that evaluated the effectiveness of certain “assist” strategies, with combinations of 1-3 assists, a truss “hurdle,” and the truss “catch.” He took student input for the point values corresponding to each action, the expected time taken for each action, and the probability of the action being carried out successfuly. He then calculated out a rough model of the weighted point values expected from strategies in the tele-operated mode of the match. The group was then able to analyze the efficiency of certain strategies. In the process of discussing strategies, the team also created two other strategy charts and lists (pictured).

Further Analysis and Prototyping

After dinner, approximately 20 students worked with the mentors to list some possible designs and to plan out the next week’s prototyping schedule. The group prioritized the prototyping of possible modules, specifically shooter designs and catching mechanisms, with design input from students and advice from our experienced mentors. They also discussed what field elements were most necessary for prototyping for the next few weeks and listed them as well. Finally, they discussed the mathematics and physics of shooting a 25-inch, compressible, bulky, and irregular projectile into a 3-foot goal. For example, mentors noted that we might as well design a robot to shoot from farther away from the goal, since the shallower angle of entry would give greater allowance for error. Mentor Paul Ventimiglia also determined that giving the large exercise ball some backspin helped in precision, though it also required more energy to apply both linear force and rotational torque.

Tonight, we mainly focused on the building a preliminary goal with which to prototype before the field arrives and on prototyping and testing the effectiveness of a flywheel shooter and a slingshot shooter. Paul worked primarily with Godwin Vincent, James Holden, Jeremy Tanlimco, Vidur Maheshwari, Miggy Francisco, and Joncarlo Avila to design, sketch, and begin building a prototype for testing the effectiveness of a flywheel on such a large game object. They determined the best wheels with which to work based on their ability to grip the surface of the unusual game object. The prototype design was finalized and they plan to use four large wheels on the same axle hooked up to curved plywood “rims” to optimize the compression on the ball and somewhat minimize the size of the already bulky prototype. EJ Sabathia and Noah Marcel worked on the slingshot design, taping a 2013 Ultimate Ascent Frisbee to surgical tubing and hooking up the system to an alliance wall. The ball consistently bounced about 1/3 of the way down the court, given about 4 or 5 feet of backward stretch.

Lab closing time: 11:00

Action Items

Translation: Future Work Opportunities for Members

• Help Paul with the Flywheel Shooter design
• Help EJ with Slingshot Shooter design
• Help Nick Mercadante machine metal for prototypes
• Ask mentors to begin and lead prototyping projects for other designs

Shockwave Wins the Abbott Invention Hall of Fame Award

Shockwave, a promotional t-shirt shooting robot, was awarded the Abbott Invention Hall of Fame Award at the 2011 FIRST Silicon Valley Regional.

T-Shirt Cannon Publicity

The T-Shirt Cannon at Your Event

Team 254 is willing and able to bring our T-Shirt cannon to many events, including but not limited to:

• Sporting Events
• Spirit Rallies
• Community Events

The T-Shirt Cannon can be branded to meet the promotional requirements of any sponsor.

To Request to have the T-Shirt Cannon appear at your event, please contact our PR Director, Godwin Vincent.

Diversity Day, 2013

On August 7, several members from our team had the opportunity to participate in NASA’s Diversity Day. As a NASA house team, Team 254 was able to present three robots; Overkill, Skyfire, and Slipstream to NASA engineers and staff who stopped by our booth.

Andrew Torrance explains Overkill’s hanging mechanism to NASA employees.

Mani Gnanasivam, James Holden, Andrew Torrance, Namit Mishra, Nick Gunady, Jack Lee, and Chris Sides attended.

After setting up the booth, the team members fielded questions from curious onlookers. Many NASA engineers were asked what program Team 254 used to design the robot, which programming languages were used, and other technical questions. All the team members answered questions asked by the dozens of people who stopped by the exhibit. After lunch, the members demonstrated Overkill’s frisbee and hanging abilities. Andrew Torrance explained multiple times to the crowd the the rules of last year’s game and Overkill’s scoring abilities. After presenting, we packed up and relaxed at the lab.

Afterwards

Sponsor Visits

Over the past three days, Team 254 has had the opportunity to visit two of its Gold level sponsors, BAE Systems and Ooyala, and demonstrate the fruits of its labor.

Richard Lin speaking to an Ooyala Employee

Overkill fully extended showing off its hanging capabilities

Students demoing Overkill

BAE Visit

On June 5, a multicultural group of five students and one mentor celebrated diversity with BAE at the BAE Systems Diversity Fair. The students participating were Nagy Hakim, Scott Cardona, Richard Lin, Abhi Kumar, and Louis Lin. Mentor Dennis Jenks provided Team 254 with the amazing opportunity to come to the fair. People in the event included many BAE engineers and programmers, who added excitement because students had a chance to talk to others who work in the same fields of interest.

Students transported two robots, Overkill and Shockwave, to the event to exhibit the team’s work and extend appreciation for BAE’s consistent support throughout the years. Many of their employees came out to visit the team’s pit and talk about the robots’ designs and controls. After opening ceremonies, Shockwave fired a barrage of T-shirts into a crowd. Later, drivers and operators demonstrated Overkill’s driving and frisbee shooting capabilities.

At the conclusion of the fair, Dennis led the students on a private tour around BAE’s impressive facility. Four tour guides exhibited the workings of BAE, including military vehicles, machines, simulations, and controls.

Ooyala Visit

Today, the team visited one of our Gold level sponsors, Ooyala. Our programming mentor Patrick Fairbank, who works at Ooyala, set the day up so the team could demo Overkill. The team visited their office, located in Mountain view and set up. There were about 40 or so members of the company that gathered around asking questions about the various subsystems and function of the robot.

Many members of the company also played Ultimate Frisbee after work on  a team. These members lined up on one end of the space set up while Abhi Kumar and Richard Lin drove the robot around, picking up and shooting frisbees towards the employees(At a much lower, catchable speed). Meanwhile, Nagy Hakim answered questions about the robot. At the end of the demo the team members stuck around for pizza and presented the award to Patrick for Ooyala’s sponsorship.

Team 254 thanks BAE Systems and Ooyala for their continued support in the robotics program.

Demo for 2013 Zero Robotics Winners

Yesterday, Mark Leon and Drew Price arranged for the current Zero Robotics Winners to tour the NASA Ames Facilities. Team 254 represented the NASA Robotics Alliance as part of the tour. The 20 or so members of their winning team filed in to the lab and were given a presentation by Abhi Kumar and Richard Lin as to the history, function, and current robot of the team. Afterwards, Abhi and Scotty Cardona demonstrated the robot’s shooting capabilities and hanging prowess. To finish off the tour, Mark took the group upstairs and talked more about the NASA Robotics Alliance and the summer Robotics Academy. As the members left, we brought Shockwave out onto the field and answered final questions for the group.

Pre-STL Day 9: Step into High Gear

Manufacturing

Students started organizing new parts into their respective bins. Most of these parts will be spares for competition. In addition, a few mentors and students worked on deburring, polishing, and touching up parts which will be sent in for powder coating and anodizing.

Drivetrain

Students contine to fix the drivetrain. A dog gear broke yet again. Students worked on taking apart the drivetrain gearbox to replace it.

Intake

Students made new parts for the intake, including new mount side plates. Additionally, students began assembling the intake support gearbox.

Shooter

Students designed a one way valve in the shooter. This stop, made from a simple piece of bent polycarbonate, will allow the frisbee to leave the shooter in only one direction and prevent it from falling backwards. This stop is a simple mechanism to further eliminate possible jams that have plagued the robot for the better part of the season.

Other

Teams 973 and 846 stopped by to the lab for practing and tuning in preparation for the World Championship next week.

Pre-STL Day 8: Rolling with It

Shooter/Indexer 

Students and mentors worked diligently to replace one of the intake rollers with a BBD. Students also worked to troubleshoot an issue with the new intake hardstop that was causing hang-ups on the intake system.

Manufacturing

Working diligently to manufacture new intake gearbox plates to save weight, students cut stock metal to be milled in the CNC.

Pre-STL Day 7: Maintenance & Anticipation

Intake

Wooden blocks were added tonight to the practice robot to keep the polycarbonate base of the intake from touching the ground. This is one of a series of adjustments to the intake to make it more efficient, fluid, and functional. The polycarbonate base often gets caught in the carbonate causing jams and reduced mobility.

Shooter/Indexer

Overkill with all of the tanks.

Even though the Frisbee hard stop was working last night, it was not today with the pin having trouble sliding the stopping plate up and down. This was solved by changing the hard stop to delrin and maintaining the mounting plates to aluminum. Also, students and mentors created two cross bars for the indexer. They also worked on shooter wheel mounting plates. Lastly, the team added temporary air tanks to the practice robot to allow for more shooting cycles and less refilling.

Drivers

Abhi and Jonathan Lee continued driver practice in preparation for the upcoming competition.

Sensors & Programming

Students and mentors tested hall effect sensors using Slipstream as a power source, because of drivers using Overkill to practice. The hall effect sensors would detect the presence of a magnetic field. When magnets are placed on the indexer mechanism, a feedback mechanism is created to determine whether or not the indexer mechanism is completely engaged in the correct position. On the programming side, programmers fine tuned various code for indexing and shooting.

Pre-STL Day 6: Packing

Today, students built a pallet to ship large items to St. Louis. They packed some very crucial items needed for Championship, including the robot cart, pit shelving, batteries, and lights for the trussing.

Lastly, programmers debugged some issues with the pit lights. The color effects no longer spawn new processes and overlap each other. Although pit lights are not a priority at the moment, students are making strong effort to make these functional to give the best appearance at the Championship event.

Pre-STL Day 5: Shopping Spree & Dieting

CAD

Today, students and mentors worked together to design new subsystems of the robot.  For instance, a new gearbox was designed for the intake lowering and raising, which would replace the current VEX planetary gearbox.  The VEX planetary was very inefficient and quite heavy. The new gearbox with its motor will be marginally heavier than the previous setup, and it has the benefit of a more favorable gear reduction. After the design work was completed and verified, the team went online to sites like AndyMark and McMaster to order these new necessary parts.  It is essential that these parts are ordered and arrive quickly, as time is running out before World Championships.

Dieting

The team is scrambling to find places to trim weight on the robot.  The new shooter wheels and intake gearbox are adding some weight to the robot, so the team trimmed some fat by removing the side panels, removing the pressure gauge support plate, and other areas. The 1/16″ side panels will eventually be replaced by side panels made of 1/32″ polycarb. Together, all the weight reductions will put us under weight. Although we are cutting it very close, we will eventually get to where we want to be.

Programming and Sensors

The programmers experimented with VEX bumper sensors as a means of detecting whether or not the frisbee is fully loaded in the indexer, and thus ready to transfer up to the shooter.  They attached two bumper sensors via double stick tape on either side of the hard-stop plate.  The next step of this is to wire the sensors to the digital sidecar and write up some codes.  When completed, the bump sensors will allow for increased speed of rapid fire. Tests will determine the reliability and durability of this setup to ensure it can survive the stresses of competition.

Pre-STL Day 4: Engineering Priorities for Time Constraints

Intake

Students worked to carefully repair the intake when it broke this morning. They had to pause momentarily to remove the intake and fix it on the side.

Fixing the Intake

Jonathan Lee debugging the robot

Design

Due to the fact that there are only two weeks remaining before World Championships in St. Louis,  a lot of the team’s new redesign ideas needed to be reconsidered realistically. While the progress of designing a bucket indexer seemed promising for spectacular scoring, it needed to be put on hold so that the team could focus on other important design tasks. In addition, it would require a major redesign or would bring up weight issues easily. The team decided to refine and work out the issues it currently has. The benefits of the major redesigns are not worth their risks, and it will be a much better use of time to work out the small issues the robot currently has.

Currently, the team is using Solidworks to design a new intake gearbox that would not make the motor burn out as quickly as the Banebot motor does now. In addition, the new gearbox will eliminate a VEX planetary from the robot.

Testing the intake Banebot motor

Another important task includes making indexer hard-stop mechanism to prevent frisbees from jamming and stacking inside the indexer. This addition is a major improvement that is a top priority. This hard stop needs to be simple, passive, and reliable. Most likely, the stop will be mounded to the conveyor side plates. The stop itself will be lowered as the indexer mechanism is lowered. As the indexer is raised, so will the hard stop to forbid the frisbee from moving forward.

Driver Practice

Abhi Kumar and Jonathan Lee practiced driving the robot around to improve positioning consistently and prepare for competition scenarios.

Abeek and JLee driving abhsentmindedlee