FRC 3061 Huskie Robotics - 2024 Season Build Thread

[10-24bolts]

Season Links

• 2024 Full Robot CAD
  • Climber CAD
  • Drivetrain CAD
  • Intake CAD
  • Shooter CAD
  • Kickoff Ideation
• 2024 Code
• 3061-lib: starter project and library focused on a swerve-based drivetrain with several advanced features
• SPOT: modular scouting app platform

Team Links

• 2023 Preseason Thread
• Team YouTube, Website, GitHub, and Instagram

Something our mentors emphasized throughout our leadership workshops was to begin with the end in mind. Therefore, we would like to start our build season thread by explaining our goals for the season and how we’ve developed them. We’ve also shared links to our CAD and code here at the top so you can easily find them throughout the season.

Goal Development

We had a mentor-led leadership workshop to learn about visions, missions, objectives, and goals during the 2022 preseason. Before the 2023 season, we noticed that “what we call our mission is not really a mission, it is just an excerpt from the Impact Award.” Additionally, many of our “goals” were objectives. Then, we had a captain-led leadership workshop to better define what our team wanted to accomplish. Captains led another meeting to refine and consolidate everything we came up with, and eventually, we developed a mission statement, four objectives, and goals to go with each objective for our 2023 season.

This year, we had everything from last year to start with. Mentors led another leadership workshop about visions, missions, objectives, and goals for members who hadn’t heard it before or were unfamiliar with the concepts. For the captain-led workshop this year, we did a top-down review of last year’s mission, objectives, and goals, noting potential changes as we went.

We started with our mission and values: the “why” behind our team. We liked the mission and thought it represented our team well, especially the parts about our community impact and making the world a better place. Then, we focused on objectives, both from the perspective of how they align with the mission statement and which parts are more/less applicable to our team. We do our leadership workshops on Zoom, so we split into four breakout rooms and had each group reflect on one objective before switching to refine another based on another group’s reflection. This allows us to get a larger percentage of the team involved while maintaining small enough groups that everyone can be heard. We had a shared doc to work on, so in between breakouts, each group could share their thoughts.

Our goals are meant to be more specific and concrete than objectives. They should be something quantifiable that we can complete within a year or two. Therefore, we started by evaluating our goals from last year. We reintroduced SMART goals and how to quantify completion as a percentage. Then, we split the team into breakout rooms again to reflect on last year’s goals on another shared document. This highlights goals that were too ambitious or too easy to accomplish, as well as goals that aren’t quantifiable. Based on this reflection, we added more specificity to our goals. During a previous leadership workshop, we also learned about Crucial Influence – proactively reducing barriers to performing vital behaviors – so we also started to think through how our different goals could address different sources of influence to better accomplish each objective.

Over winter break, captains reviewed the documents and incorporated the changes for this season. Here is just the document with the changes we made highlighted.

Here are the changes we made and why for each objective and set of goals:

Maintain and Build Relationships with the Community

We didn’t change this objective. For goals, the team focused on adding relevant specificity. For example, we changed our goal from everyone on our team having 8 service hours to 80% having 8 and the median being 11 hours. This is more realistic and highlights how frequently we want members doing more than the minimum. We also changed from each district FLL team having at least one student mentor to the assigned student mentors participating in at least one meeting each week, which better defines the support we want to provide. We moved winning the impact award to our fourth objective, Become a World Class Robotics Team. While this objective can contribute to winning the Impact Award or Engineering Inspiration, winning those awards isn’t a requirement before we can engage with our community.

Strengthen our Robotics Family

We reworded the last sentence to clarify the purpose of this objective. This objective is one that we’ve struggled to come up with specific goals for. We removed our goal to do surveys of team members because we didn’t do it last year and we think there are better ways to strengthen our family. We also added three new goals. We want to help every member find a subteam they enjoy, model team values starting with the leadership team, and have a team value moment every week.

Prepare Team for the Future

We added “leaving comprehensive notes” in addition to training, certification, and workshops “to create valuable resources that prompt collaboration.” We added more specificity to these goals. We defined “certified in one subteam” as “certified in at least 50% of subteam processes” to allow for new members who are still learning. Instead of “work on large projects,” we quantified it as “explore at least one major project in each subteam.” We considered specifying completing 4 FPM projects but decided to focus on subteams instead to ensure growth across the whole team. We added a deadline to when we want subteam standardization to be navigated by new members. We also added a goal to retain 80% of members throughout the season so that everyone gains experience and can continue to pass down knowledge.

Become a World Class Robotics Team

We removed the explanation of the world championship and added being both a member of the Open Alliance and a sustainable model for other teams to this objective. For goals, we added having no major failures, winning the Impact or EI award at a competition, and posting weekly for Open Alliance throughout the season. We also added building a robot that meets all design requirements. These are all goals that we met or almost met during the 2023 season or preseason, and we defined them to remind us to continue our efforts in these areas.

Mission, Objectives, and Goals Development Resources

• Mentor-Led Workshop
• Captain-Led Workshop
• Captain-Led Slides
• Objectives Reflection Handout
• Goals Reflection Handout

Mission, Objectives, and Goals

• 23-24
• 23-24 with changes highlighted
• 22-23

[Aayush_Modi]

Huskie Robotics Kickoff:

This past Saturday, Huskie Robotics held its annual Kickoff meeting! Each year we get together as a team at our school to watch the release of the game together as well as meet the many Huskie Alum that are in town for winter break. We are super excited about this year’s game and honored to be recognized along with 1678 Citrus Circuits as one of the two Game Design Challenges used as inspiration for the game! Here is the link to our Game Design Challenge: Operation Radiation Game Design Challenge: Operation Radiation.

We made many changes to our kickoff schedule this year, as we wanted to be more inclusive in the different ways people solve problems and the different things that they have an interest in. This schedule allowed us to give more flexibility for our members to either focus on brainstorming designs or the overall strategy of the game.

Before kickoff, members volunteer to read a specific part of the rule book if they want and summarize that within our Game Rule Summary Document. After the game is released members meet with others who choose to break down the same section and go through the specific part of the rule book with each other. After the groups are done, they present to the whole team so that everyone has a chance to understand each part of the manual and the most important rules. We choose to break down the rules this way as it gives us more time to brainstorm and create designs.

This year we decided to take a new approach to the way we organize our kickoff brainstorming groups. Instead of splitting up our FPM (Feature Project Managers) by predetermined subsystems and having them start creating their design at kickoff based on these decisions. We decided that it would be best to split up FPMs based on the game pieces and have them focus their brainstorming groups with the goal of how to score a specific game piece. In this year’s game, this became scoring the notes and scoring on the stage. The designs that were made focused on a complete robot rather than specific subsystems on the robot, allowing us to not limit ourselves to a specific amount of features like in past years. This new approach turned out to work well because as the various groups were brainstorming numerous designs, our strategy team refined our approach to the game and gave continuous new design requirements to help the teams refine their designs. Also, because we are such a big team, splitting up into groups allows us to make sure that all members have a voice in brainstorming.

We let groups brainstorm their designs for about two hours before we got together as a whole team and shared out. Each group presented their design and how it functioned then answered questions from the team about any concerns or confusions they had. This process allows everyone the chance to share the different designs they made. You can view our group designs here: Group Designs

To best suit our strategic interests, we have broken our robot down into four different components and began establishing requirements for each.

Overall

• 2’ 3.5" max height
• Meets all robot rules
• Able to withstand collisions of any speed

Shooter

• Able to score in both the amp, speaker, and trap.
• Adjustable angle greater than 90 degrees
  • Help shoot in amp and in speaker from against the subwoofer
• Be able to score in Trap

Intake

• Under the bumper intake
• Double-sided intake on opposite sides
• Touch it own it

Climber

• Be able to support the robot on the chain with at least 1 other robot
• Raise the robot off of the ground

Drivetrain

• MK4i swerve drive
  • Be as fast as possible
• Clearance for notes

We will be sharing more designs and prototypes later this week!

[gcschmit]

We just released 3061 Lib v2024.0.0. For more details, including if this may be useful for your team, refer to this thread.

[gcschmit]

Molex Hand Tool Kit in FIRST Choice

Our team is fortunate that Molex is headquartered down the street from our school and they support our team in so many different ways. We wanted to make sure that everyone was aware that Molex has donated their Hand Tool Kit in FIRST Choice round 2. The deadline for FIRST Choice round 2 submissions is January 16th.

We switched to Molex SL connectors two years ago for our CAN bus and low-amp power and haven’t had a single on-field failure. (We used Molex MiniFit Sr. connectors for our 12 AWG power wires for years.)

We have a lot more to share in this thread regarding our best practices for CAN bus wiring. We are currently evaluating a few changes to increase reliability, facilitate troubleshooting, and maintain serviceability. But, we wanted to make sure everyone was aware of Molex’s new kit in FIRST Choice!

[Richard_McCann]

Congrats on having your 2021 Game Design Challenge concept used in Crescendo!

[gcschmit]

Likewise!

[Aayush_Modi]

Week 1

We have had a very cold but productive first week here at Huskie Robotics. Our features have been busy working on creating prototypes and CADing various mechanisms. Here is an overview of what each Feature Project Manager has been working on:

Intake:

So far, we’ve had about a week since Kickoff, and we’ve picked a design and started prototyping. On Kickoff day, we decided to do a double under-frame intake for the notes. We were planning on using some sort of rollers and/or ramps to lift the notes up into a central area on top of our robot, where they would then flip around a drum (like paper in a printer’s paper feeder) where they can be staged until we are ready to release them into the shooter. Here’s our ideation cad, from a couple of different angles.

With Krayon CAD Drivetrain:

Rollers:

Drum:

Then, we moved into prototyping, starting with the rollers that will pick the notes up from the ground. We tested three different options: two shafts of stealth wheels, a hex shaft and ramp, and two shafts of sushi rollers.

The first idea that we prototyped was two shafts, with some 2-inch stealth wheels on them. We built a rough, adjustable frame out of REV extrusion and mounted both shafts, each spun with a drill. We then mounted the whole frame onto a furniture dolly so it could be pushed around our field carpet to try picking up some notes.

It was not that great, as one issue that we had was the note not riding on top of the second roller, and instead trying to go into the carpet. It was also not lifting the note either as high or as quickly as we wanted.

Next, we tried a hex shaft, which we wrapped with some grip tape. It would intake the note, and then the note would be pushed up a polycarbonate ramp.

This method worked better than the wheels, but it seems to be sticking onto the polycarbonate instead of sliding. After looking on Chief Delphi, we couldn’t find anyone who had posted quantitative note friction data, so we decided to do it ourselves.

Methodology: We wanted to see how slippery different materials are against notes. We placed a note on each material supported by a strong backing surface. Then, we slowly lifted the surface until the note began to slip, and recorded the angle with a digital angle measurement tool. Below is the angle that each material was able to hold the note up to before it started slipping, in order from least to greatest. A higher angle means more grippy/sticky and a lower angle means more slippery/sliding material.

• Field Carpet: 13.9°

• Orange Peel HDPE (material used on the Chute last year and in the Source this year): 17.1°

• HDPE plastic(material used on the Charge Station flaps last year): 17.8

• Bumper Patch Fabric: 17.9

• Cardboard: 22.0

• Huskie Robotics Tshirt 25.0°°

• Back of whiteboard: 27.0°

• Polycarb: 50.5°

• Front of whiteboard (where you write): 57.5°

After excluding the field carpet because it’s not feasible for our robot, we then tested the three next best materials (Orange Peel HDPE, HDPE plastic, and bumper patch fabric) three more times each.

Material	Trial 1	Trial 2	Trial 3	Average
HDPE Plastic	16.1°	15.5°	16.7°	16.10°
Orange Peel	17.9°	17.4°	17°	17.43°
Bumper Patch Fabric	25°	22.7°	23.5°	23.73°

Based on our data, we chose to use HDPE plastic for all further ramp tests.

Our final prototyping idea for the rollers was to use two shafts of sushi rollers. The note would roll under the first roller, over the second, and then finally up a short ramp until it ended on top of our robot where we wanted it. This idea worked the best by far, and here’s a video of it in motion.

Rollers Prototyping: Best Test.mp4

Then, we worked on prototyping our drum. First, we did some integrated testing with both the existing rollers and a drum. We got some 4” compliant and stealth wheels and attached them perpendicular to the existing rollers.

Here’s a video: IMG_5757.MOV

After that, we did another test with just the drum and the hood. After trying 4” flywheels and 4” drive wheels, we settled on 2” stealth wheels. Next week, we’ll start designing our final intake!

Drivetrain:

This week drivetrains’ main priority was CADing. After kickoff, some important elements for the robot were decided. The chassis this year is going to be 28x28, we will be using Mk4i swerve modules and the 2 intakes are going to be under the bumper, which affects the layout of the drivetrain. The first change that needed to be made was that we needed space underneath the robot for the notes to go. Instead of having a 2x1 for the outer rail on all sides, the intake sides were changed to a 1x1. We worried about the weakness of these two sides, so we made the 1x1s solid aluminum for strength.

As the intake takes up the sides of the robot, our electrical board cannot be spread out across the chassis and is constrained to the center of the drivetrain. As a result of this constraint, we decided to move the battery to the front of the robot so that it was out of the way of the shooter and intake and easily accessible.

Originally we were going to go with a double-sided electrical board that extended up into the robot, but it was decided that the intake needed that space to house and move the notes up to the shooter. So we were challenged to find other space for the electrical board. After talking with our electrical team we first decided that the PDH, roboRIO, CANivore, and pigeon were going to be in the center cavity of the drivetrain. After further discussion with intake, it was determined that there would be space above and around the intake to put more electrical components. We are waiting to confirm the exact spacing until we know more about the intake.

Other than these main changes we created a back plate for the battery, which will be held down by a strap, and we also started the assembly workflow.

Climber:

So far, we have been trying to figure out what the best way to get on the chain and meet our design requirements is. Our design requirements for this year for the chain are to reach up to just under the maximum height (47.5”) and pull the robot 14” off the ground to the bottom of the chassis. Our time frame is 5 seconds for the whole sequence, from the point we touch the chain to the point we score in the trap. We are also trying to be able to harmonize with other robots. We have found that telescoping arms from 1-4 stages don’t satisfy our requirement of 14’’ off the ground, but stages in our case got us 3’’ off the ground. We did the calculations off the GreyT Telescope.

We also worked on some ways to hold on to the chain at any height without sliding down. The first design is a profile of the chain to try and catch the chain. The second design is to try and fit
onto the vertical slots of the chain.

Some of the different ways we are looking at climbing involve using ropes and winches, as shown in this sketch:

Or using something like Spectrum and their climber shown here.

Shooter:

So far the shooter has done brainstorming/prototyping and a lot of geometry. The shooter consists of the speaker, amp, and trap scoring mechanism in that priority. At kickoff and coming into our first meeting we narrowed down the general mechanisms to two ideas. One idea was horizontal bars of rollers. We decided to try using 2.5-inch wheels on one side and a piece of bumper patch fabric on the other.

This prototype did not live up to its expectations and did not shoot very well at a 1.75-inch compression; there was just too much friction on the game piece from the plate for it to get any distance. We tried using 4-inch flywheels to add more inertia but that did not help much and the shots were far too inconsistent to become a viable solution. What we learned was that you need to feed your mechanism consistently to shoot consistently from this design and that spin may be more important than we thought to keep the note stable. You also need to have a flat surface after the last roller to keep the note from going up or down.

The other idea we had a kickoff is a horizontal wheel shooter like most teams in 2013. We built a prototype last meeting and will continue to test it but it looks promising as the notes fly more consistently in the air.

We started out with a 5” comparison and a vertical compression of 0”

We also have done some CAD geometry for the amp scorer. Our current idea is to back into the amp and use a deflector with rollers that rotate out on a pivot at the end of the shooter redirecting the note into the amp. This design can be later extended to mounting this rotating deflector on a slide to carry the note into the trap.

[Aayush_Modi]

Week 2

Week 2 here at Huskie Robotics has been filled with more CADing and Prototypes. We have made tremendous progress towards finalizing designs and some features have started to fabricate certain parts! We added each feature’s CAD document to our initial post with the rest of our season links. Here is an overview of what each feature did in week 2.

Intake:

This week, Intake started strong with the beginning of roller CAD. By mid-week, we had a rough design.

If you haven’t been following along, we’re doing a double under-frame intake, so most of the images will only show one set of rollers, even though in the final design we’ll have two, one on each side of the drivetrain. Throughout this process, we ran into two major design challenges.

The first challenge was attaching our top roller. Our first design (above and below) uses a custom bearing block and MAXTube end cap to attach our upper roller directly to the outer rail of the drivetrain. To easily remove this roller (in case something breaks during a match) we created a 3D-printed clip (middle orange piece) that can be removed from the roller. This creates space on the shaft for the shaft collar and bearing to be slid to the right. Then, the hex shaft could be slid out of the cutout in the bearing block. However, this design wasn’t strong or accessible enough, so we moved on to the next.

Our second idea was to use an extra-large (⅞” long) shaft collar as a coupler to attach the top roller to a shorter shaft. Then, the shaft collar could be loosened, the small hex shaft could be removed from the bearing, and the top roller had room to be removed. This idea is swappable faster than the first idea. However, we still have the issue where the intake is not one cohesive assembly, because most of it is attached to the top of the drivetrain but this one roller is attached to the outer rails.

Finally, we decided to move the roller a little bit in order to make our side gussets hold the top roller too, along with the bottom roller. In hindsight, it was obviously the best idea. The entire intake roller subassembly is now cohesive and can be easily swapped with a spare in the pits between matches by only de-riveting the top gussets.

Our second design challenge was our motor mounting. First, we planned on using a Falcon 500 directly driving the rollers, but then we realized that it had almost no ground clearance (.1” to the tip of the swerve tread).

So, we switched to a NEO 550, but we were concerned that, even with a 1:3 Ultra Planetary gearbox, it wouldn’t have enough torque to bring the notes up through the rollers.

Due to this, we realized that we had to make the Falcon fit somewhere. Eventually, we were able to make a cutout in our backing gusset to make the motor fit.

Near the end of the week, we had our roller design reviewed by our mentors, captains, and coaches. After completing those CAD changes, here’s our latest CAD.

We’ve also started on some CAD for our drum and intermediate roller. These will bring the notes to the back of the robot to hand off to the shooter.

In conclusion, here’s the Intake CAD, as it stands (on the drivetrain for reference).

Also, currently, each roller assembly weighs approximately 4.96lb [2.25kg]

Onshape CAD Link

Drivetrain:

This week the drivetrain continued our work CADing the feature. After the frame was CADed last week, we have mostly been working on a lot of small but important details. We added some of our electrical components in the center cavity of the robot and began to map out where our wires will go. It was also decided that our battery needed extra support on the sides so we added 3D prints that will help keep the battery in place. These 3D prints are screwed in through the bottom of the battery plate, so we ended up making changes to the plate as well. The 3D print on the bottom right corner is shaped differently to allow the battery cables to go through a hole in the 2x1 into the electrical cavity.

As the week has gone on, we have learned more about how the other features will look. This is very important for figuring out how to mount each feature to the drivetrain. Some gussets and holes in the rails have already been added to accommodate for the intake and we are continuing to change the CAD for the other two features.

We have also begun creating the bumpers in CAD and modifying the bumper gussets to fit the drivetrain.

This week we held our first design review, in which we talked about the positives of the design and some things that needed to be changed. During this discussion, we decided that a few of the parts were ready to be made, and we were able to fabricate some of our first parts for this year’s robot.

Finally, we started our FMECA worksheet and software feature sheet and continued working on the assembly workflow.

Climber:

This week, we decided to use a winch for climbing. We crunched some numbers and used ReCalc to figure out the gear ratios necessary for the winch. Our idea involves having two winches, one on each side of the robot. However, for our calculations, we focused on just one on the chain to account for the risk of missing the chain or one hook falling off.

Here is the link to the “Best Case Scenario”.

Here is the link to the “Suboptimal Scenario”.

We plan on using Krakens for the motors. We found that a 25:1 with a 1” spool diameter worked best for us. We plan on making a frame out of REV extrusions to mount a winch and some weights on to see how the winch holds up when weight is put on it. We also looked at some different options for raising the hook from the robot up to the chain. We are looking at using something that uses a spring-like effect similar to Orbit in 2018. We fabricated a segment from ⅛” thick polycarbonate measuring 30” by 1.5”. However, we found it to be too flimsy for our specific requirements. We looked for some alternative materials that share similar traits which led us to look at fiberglass rods. We’re waiting for some to come in and hope to do testing early next week.

Shooter:

Week 2 has been quite a week for shooters to start. We tested our horizontal roller shooter with 5 inches of compression on the note and 2 plates, 2.063 from each other, on top and bottom. We used two 1:1 falcons to run each side and found that the best shots at full speed were at 12 V and 8 V. Our first attempts were using 60A black stealth wheels. By the end of the test they were orange from the note dust (the forbidden cheeto dust). This told us that we needed more friction to minimize the slip between the wheels and the note so we switched the back two flywheels to 60A compliant wheels. This made the shooter slightly more accurate. If teams want to go with this design I would recommend a 40A wheel.

Side flywheel consistency test in speaker

img_2294.mov

Side flywheel consistency test

IMG_2841.MOV

With this we decided we were ready to start CADing the final design. In the final design we incorporated a third set of wheels at a higher durometer to kick the note from the intake into the shooter.

We then had our high level integration and system overview meeting where we realized that the flywheel shooter would need major changes in order to integrate properly with all the other features.

After looking at some other OA threads most notably 111’s shooter prototype we decided to try to replicate the consistency of their prototype. We laser cut a prototype with two 1:2 falcons with .5 inches of compression and 12 inches wide. This was by far the most consistent shooter design to date.

Shooter range test:

IMG_2373.MOV

Shooter trajectory from wing line:

IMG_2364.MOV

shooter consistency test:

IMG_2348.MOV

In parallel, we have also been working on the amp and trap scoring device (the deflector) which attaches to the end of the shooter. This deflector uses a HDPE hood like the drum as well as 2 ⅜ stealth wheels. We prototyped this and it was successful in flipping the note from the shooter with the right hood geometry

We are now working on the CAD for the shooter. We will be using 2 Krakens (hopefully if they arrive before we build) diving top and bottom rollers made of 40A stealth wheels. And we will be using polybelt to feed the notes from the drum into the shooter. The polybelt kickers will also drive the deflector.

[nuclearnerd]

@Aayush_Modi

In parallel, we have also been working on the amp and trap scoring device (the deflector) which attaches to the end of the shooter. This deflector uses a HDPE hood like the drum as well as 2 ⅜ stealth wheels. We prototyped this and it was successful in flipping the note from the shooter with the right hood geometry

I really like the deflector design - we’re taking notes! How do you plan to deploy it over the front of the shooter?

[Lotem49]

Our plan for developing it is to have a gear with most of its teeth taken out at the base of the shooter then a gear connected to the shooter that only interfaces and spins on the partial gear above a certain angle (because past 65 degrees ish we can no longer physically score in the speaker). We will then carry that rotation up the shooter with a belt to flip out the deflector.

We were planing to put a motor dedicated to flipping the deflector up but shooter went past our motor quota and we needed to use the motor elsewhere.

[angelajp7]

Practice Bot:

This year we created a 28x28 mk4i swerve drivetrain for our practice bot. By taking our mk4 modules from our 2022 Rapid React competition robot, we upgraded them to mk4is, allowing us to assemble a second swerve robot in addition to our 2023 robot, Nova. We took the A-frame and elevator off of Nova to lower the center of mass, allowing us to drive faster and accelerate more quickly, which also removed our cameras for April Tags. A separate practice bot will allow our software and drive teams to work on auto paths, characterization, and run cycles without waiting for our 2024 competition robot. While we had a practice bot last year at the beginning of the season, we needed to use its swerve modules on the competition robot, so it ended up as an excessively large electrical test board. We also took this practice bot as an opportunity to test out L3 gears on our swerves, a new CAN wiring topology, and a new bumper mounting solution.

Here is a picture of our new CAN topology, which we plan to use on our 2024 robot as well. We did this for increased reliability, and there will be another post about this in the upcoming weeks.

Last year, we started with a draw latch solution that turned out to be weaker than we had anticipated. After our first competition, we switched to captive nuts within the drivetrain rails that we secured with ¼-20 bolts through the bumper L channels. For the 2024 season, inspired by Citrus Circuits, we secured bumper gussets to our MaxTube drivetrain rails and a bolt to our bumper wood that sits in a slot in our gusset. This bumper mounting solution increases our frame perimeter by 1/8" on each side, so we also added 3D prints extending past the corners of our swerves to support the bumpers. For the practice bot, we’re using 1/8" gussets without a circle imprint to hold the nut down, but we plan on making our competition bumpers more secure. We can secure the bumpers by ratcheting a ¼-20 locknut in 8 places around our drivetrain to secure our bumpers. We really like this solution because the nut can be loosened enough to remove the bumpers without taking it off completely, so we won’t need to keep track of bumper hardware like we did last year. Here are some pictures of our bumper mounting in CAD and on the practice bot, as well as a photo of the bumper wood without pool noodles.

On its own, this practice bot weighed about 48 pounds without bumpers, so we added 60 pounds in ruck weights to simulate the weight of a real robot, allowing our software and drive teams to perform accurate testing. We also mounted two cameras so that we would be able to incorporate vision into our auto paths. These are mounted on 3D prints on 1x1s and are angled up 45 degrees. By CADing accurate models of the cameras and placing mate connectors at the lens of each camera and the center of the robot at carpet level, we can easily measure the location of each camera. This allowed us to easily have an accurate location even after switching which side of the 1x1 each camera was on and adding spacers to prevent the cable from getting squished.

[angelajp7]

Week 3

Intake:

This week, Intake has been continuing our design of the subsystem. After three mini-design checks, we have finalized the rollers and have fabricated about half of the parts so far. We hope to get started assembling next week. We’ve also started working on our CAD for our drum and transition.

Here’s the transition. It pulls the notes out of the rollers and rolls them towards the drum. It’s powered by a motor (not yet pictured) that also powers the drum via a belt. The big triangular-shaped wedge is a guide that will ensure that the notes go toward the back of the robot and that there is no possibility for a note to get stuck in the intake. For us, this is an avoid-at-all-costs scenario, as said a stuck note would be our single game piece, and we would not be able to intake any others.

And here’s the drum with the part of the drum hood that Intake is responsible for (the stationary part). The part of the drum that rotates with the shooter (and attaches to the shooter gusset) belongs to the shooter.

We’re working very closely with Shooter in order to manage this possible interference point, especially because the shooter drum hood will be moving very quickly and we don’t want anything to bind. In total, here’s our intake so far!

Drivetrain:

This week the drivetrain was busy finishing up most of the CAD. The big changes to the mainframe included the addition of polycarb walls and holes in the solid aluminum outer rails.

The first change that we made was putting walls on the non-intake sides of the drivetrain. These walls were put here to ensure that notes do not go under our chassis and get stuck. These walls are made out of ⅛” polycarb and are riveted onto the 2x1 tubes.

The other main change that we made was in the solid aluminum 1x1s. Tapped holes were added every inch along the top face of the one by one, and on the side face the same holes were added but offset by ½”. The reason that we did this was because the outer rails are an important part of the assembly of the chassis, but we were unable to print them as we didn’t know how the other features were going to mount to it. With these tapped holes we are able to fabricate this part as the other features have plenty of mounting holes

The other big thing that we CADed this week was the bumpers. The bumpers are held on by a nut and a bolt-type attachment, taken from Citrus Circuits 2023 robot, connected to the bumpers. Here is what the top of the bumper gussets, where the bolt holds it in, looks like:

We also had to resign the gussets for the intake sides, so they ended up looking like this:

Another thing we had to change about the bumpers was the height. We had to redesign them to be higher than they were in previous years to work with the intake. They are ¼” below the height limit.

Climber:

This week, the climber has been focused on finalizing the winch design and completing the CAD. We encountered challenges in determining the optimal placement for the winch and ensuring a proper fleet angle with the arms. Initially, we experimented with relocating the winch to various positions around the robot to achieve the correct dimensions. However, despite our efforts, we faced difficulties in making it functional.

In response to these challenges, we shifted our focus to exploring using fairleads to guide the rope into the winch. Currently, fairleads are the solution we are using to address the issue.

In addition, we started thinking through where our arms would connect to the rest of the robot. Due to the transition and shooter, this is a major integration challenge. The plan is to mount 2x1s to the end of the drum dead axle with standoffs to keep it from rotating and then put a pivot at the top with a torsion spring. Because we’re lifting the robot with the winches, this part of the climber only needs to be strong enough to lift the hooks.

Shooter:

Shooter has been hard at work designing and integrating the shooter to the robot. The following are some highlights of what we have worked on but I recommend taking a closer look at the CAD found here.

This week we finalized our mounting on the drivetrain using a combo of rev ion structural endcaps to go into the inner rails.

We will drive the shooter with a 100:1 gear ratio using a 25:1 rev planetary and a 4:1 ratio using gears.

We will use a polybelt as a kicker for the note. The crowned pulleys are 3d printed.

The shooting path will be lined by PTFE (Teflon) stickers on a 1/16 inch polycarbonate plate backed by lightened ⅛ inch aluminum

We will finalize the design this week and will start fab this week. There are 5 motors on the shooter 2 Krakens that will spin the shooting wheels, 1 Falcon pivoting the entire mechanism, 1 Falcon that will spin the kicker wheels and the wheels for the deflector that scores in amp and trap, as well as 1 Falcon that will pivot the deflector. An IR sensor will detect the game piece and a cancoder on the pivot output shaft will detect the absolute angle of the shooter.

[hage-043]

@Aayush_Modi

We are also trying to be able to harmonize with other robots. We have found that telescoping arms from 1-4 stages don’t satisfy our requirement of 14’’ off the ground, but stages in our case got us 3’’ off the ground. We did the calculations off the GreyT Telescope .

Would you guys mind sharing the calculations/formulas you used to determine reach based on tube length for the WCP GreyT telescope?

[gcschmit]

We took a photo (below) but a lot isn’t captured. We were attempting to satisfy two design requirements with these calculations: 1) reach 47.75" from the ground to grab the chain; 2) climb to a point where the chassis was 14" off the ground. The equation in the top right of the image is most relevant. We were solving for the minimum length of the base stage that, when combined with other stages (2 in this case), would reach the chain at 40" (40" from the mounting point of the base stage, excluding the length of the hooks). The +1, +1.25 is from the GreyT telescope guide. The 2 * 3.6" term is the minimum overlap between stages due to the bearing block.

[gcschmit]

For the past few years, the team has benefited from a few mentors who redesign and build the field elements. We usually build a half-field worth of field elements (team versions). The strategy sub-team determines the priority of construction. We always modify the team versions to facilitate transport through the school and setup. Besides athletic areas, there is only one space in the rest of the school with a high ceiling – one of our cafeterias. We are fortunate to have access to this space most (but not all days). That said, we have to move all of the tables, roll out the carpet, and assemble the field elements at the start of each meeting. We then have to put everything back at the end. Therefore, we try to modify the team version of the field elements to make them easy to transport on furniture dollies, able to fit through a standard door, and reasonable for students to assemble quickly (with few or no tools). In addition to these requirements, we also modify the team version of the field elements when we think the dimensions or materials may impact performance. For example, two years ago the material of the hub had a significant impact on the cargo scoring or bouncing out.

Here is our speaker, driver station, and amp. They will be adding the subwoofer side and middle panels.

We did change the materials of the speaker and amp where they will contact the notes to ensure we aren’t surprised at the first regional.

They also built a box around the stage feet to ensure as the exact size is important for autos and alignment to the podium. A 1/4" x 24" x 24" sheet of plywood will be added to the bottom.

We did decide to purchase one trap from AndyMark to ensure that we practice with a mechanism as similar as possible to the competition version.

They built two of the team versions of the stage. They then reinforced this elements, added latches to connect them together, and cut removable 4x4s such that the two stages could be connected and the middle feet removed. This allows us to drive under the stage just like on a competition field.

We can climb on either of these two stage parts, just not the back of the stage. We have one official microphone for human player practice, but they will be installing a second one made from PVC pipe.

If you have any questions about the modifications that we made, feel free to ask, and I’ll pass them along.

[angelajp7]

Week 4

Intake:

This week, Intake has been assembling. We’ve run into a few small issues with parts not all being fabbed at the right time (lower priority parts got fabricated before higher priority parts by accident) and some parts that we needed for assembly were not approved and therefore not sent out until we really needed them. However, we’ve overcome those roadblocks and have assembled one set of rollers (excluding the motor, the Falcon pulleys haven’t come in yet). Next, we’ll work in parallel with the other set of rollers and the transition and drum. Here are some photos of the roller assembly!

A project management tool that our team uses is called FMECA+ (Failure modes, effects, and criticality analysis). This is a modified version of an industry-standard tool that you can learn more about in our FMECA leadership workshop. It’s a spreadsheet where we document what can go wrong - mechanical (something breaks), electrical (something gets unplugged), and software (code goes haywire). We then decide how often it could happen (on a scale of 1-10) and how bad it would be if it happens (1-10). We then multiply those numbers together to get a Criticality Number. Depending on what range it falls in, we either need to make more changes, add it to our pre-match checklist (ie “check the bolts before each match”), or that we have properly mitigated the risk. Here’s some of the possible failures that we have documented for Intake.

Drivetrain:

This week was a slower week for drivetrain as we were waiting on parts to start assembling. Something that we need to do before starting assembly is putting rev endcaps into our inner rails. As of the beginning of the week, REV was out of stock of these, so we CADed 3D printed replacements, with a captured nut inside. Thankfully, they came back in stock, so we ordered them and received them this Saturday. This means that we can start our assembly first thing next week

We continued to take inventory of the parts we have and ordered more. Plenty of parts have been or are in the process of being fabricated. While this process is continuing, the parts list status update is getting updated. Parts list status updates is a spreadsheet we started last year and further developed going into this season that allows us to keep track of part statuses before they go on the robot. Here are some of the parts for the drivetrain:

Drivetrain finished making the assembly workflow for the frame of the drivetrain. We also created a workflow for changing the Mk4i swerve modules to L3+ as well as having started work on the bumper assembly workflow.

Since our robot is so packed this year and we have an under the bumper intake, there is not enough room in the electrical cavity for all the components we need. Drivetrain designers and the electrical subteam worked together to figure out where we can put the rest of the electrical board, and how we can run the wires throughout the robot. We have a general idea of where everything is going to go and we began CADing the rest of the electrical parts into our robot CAD. We decided to split the rest of the electrical board on either side of the robot, above the intakes.

Climber:

This week, the climber team has been working on prototyping to observe how the robot behaves with our winch and arm setup, as well as determining the location for our support wheels on the shooter. Through this prototyping process, we discovered that the wheel placement was too low. When we initiated the climbing sequence, the robot would rotate, causing the wheels to fall beneath the stage. To address this issue, we will need to add wheels to the end deflector of the shooter to elevate them and prevent this during the climbing process. In terms of design, we reduced the height of the winch so that we could climb higher. We also added rollers to the top of the motor using Delrin and standoffs screwed into a C-channel to help guide the rope. CAD-wise, we have completed the CAD design for the winch and made significant progress in CADing the arm. We ordered and started fabricating parts for both of these mechanisms.

Shooter:

Over the past week, shooter has finalized its design and been sent out to fabrication. Over the past couple of days we have CNCed and Machined 50% of the parts for shooter and most of the COTS parts will arrive this week. Below is a picture of the ⅛ inch aluminum plates for shooter (not the pizza)

We are currently in the process of creating our assembly workflow. This year, more than most others, we have prioritized working in parallel and are thinking of ways to assemble most effectively. Some parts haven’t come in yet, so we want to ensure that we finish as quickly as possible once they arrive. We are also thinking about assembly as we are in the process of completing or FMECA+ process for risk analysis (see intake for full explanation).

[Aayush_Modi]

Week 5

Sorry for the late week 5 post, we have been quite busy assembling our various features. Expect a more in-depth week 6 post coming soon!

Intake:

This week Intake has been assembling and testing. We’ve been testing the rollers, along with assembling the drum and transition. The drum was just assembled and is being integrated into the shooter. The transition is mostly assembled, however we are just waiting on some belts to come in to finalize the assembly.

We’ve also been testing the rollers (independently of the rest of the robot). Here are some of our testing videos!

Throwing Notes In.mov

Pushing Notes In Slo Mo.MOV

Finally, we’ve noticed that with our new batch of notes, our Intake no longer works. This is because they are way stiffer and don’t want to bend. We’re undergoing a redesign to make it work, and we will share more about the results next week.

Drivetrain:

This week, the drivetrain assembled the frame of the chassis and was able to put components into the electrical cavity. We continued to wait for the L3 gears but were able to rebuild one of our swerve modules with L3+. We worked with electrical to continue CADing in the rest of the electrical board and decide a route for the wires to go. We added polycarb walls to the side of our robot to protect from other teams above the bumper intakes. During week 6, as the other features finish up their individual assembly we will start mounting them to the drivetrain and putting on the swerve modules.

Climber:

This week, Climber has been focused on finishing the arm and creating a second version of it. The two versions we have are the Normal/Long Arm and the Short Arm. The Short Arm is specifically designed to function effectively at the middle of the stage to score in the trap, while the Long Arm will be used when we aim to climb anywhere on the chain. Although it can score in the trap, our primary intention is to utilize it when harmonizing with another team. The arms will be easily swappable between matches, depending on the capabilities of other teams in alliances. Additionally, we have been working on prototyping the new arm lengths and the new wheel positions mentioned last week due to encountering issues with dipping below the stage. We are also continuing to prototype the best hook designs for our use case.

Shooter:

This week the shooter is in full assembly mode and hoping to finish the assembly Thursday. We recieved most of our parts from our CNC and Machining subteams and are ready to assemble. The plan is to get the shooter assembled, then mount it onto our drivetrain chassis. Shooter needs to be mounted before any other features can be attached, so it is a very high priority at the moment! We will update you with any issues we run into in our week 6 post!

[Aayush_Modi]

Week 6

As 111 once said:

Week 6 was one for the books here at Huskie Robotics. Lots of lessons were learned and changes made. I will let the FPMs elaborate more:

Intake:

Throughout our testing at the start of this week, we realized that, regarding the first batch of notes, our intake doesn’t work as well as we want it to. Regarding the second, stiffer batch of notes, our intake did not work at all. Therefore, we did some iterative prototyping. Now, when we say iterative, we mean iterative. We ran out of laser-cut plywood!

There were two options that we were considering - a modified version of our current design and another design where the note would be kicked up off the ground and then pressed against our HDPE backing. Here’s the second - where the note gets kicked off the ground - for these photos green circles are 1” sushi rollers and the orange line is the path of the note.

Here’s the other option - which is a modification of our past design - just with compression that would work better for the new stiff notes.

One important fact to note is that for all of these new designs besides varying roller placement, we also made the intake 2 inches wider, so less side-to-side compression. Now we are only compressing the note to 12” instead of 10” (from 14” outside diameter). We also briefly tried a triple roller design…but it wasn’t the best for us as it “shot” the note out too vertically, instead of horizontally into our transition. In the end, we went with the second design shown here - where the note hits the top roller first to ensure touch-it-own-it. Our biggest breakthrough this week was tiny rollers - .5” diameter Delrin bolt spacers over a #10-32 bolt. We bolted those to our prototype, and it made such a big difference! Now, the note is no longer rubbing against the corners of the wood, and it smoothly intakes. Due to this, we want to implement these rollers wherever the note has to take a sharp turn, both vertically and horizontally.

We’ve now created a new side plate for our prototyping setup where we use lots of those rollers to guide the roller from its angled ascent to be flat. (tiny rollers are blue, and this plate has two options for the rollers - an arc or a flat line)

This prototype worked, and now we begin the CAD-redesign.

We’ve also been working on redesigning our transition/drum mechanism because our compression of 1.75” (which worked during prototyping) does not work when we have the real feature in our hands. We’ve been trying polybelt, along with a better drum hood mechanism. This photo just about sums up this entire week, which was a lot of redesign and new solutions.

This week, and in the next three weeks leading up to Heartland, we will hopefully quickly finalize all of our roller placements and swiftly redesign the Intake. If you have any questions, or suggestions, or would like some more information about our second wave of prototyping, feel free to comment!

Drivetrain:

This week, the drivetrain was not able to continue assembling the chassis as the shooter was mounting it and testing it. Our next step in assembling the chassis is to put on the swerve modules and side outer rails. However, this assembly will have to wait until the shooter is finalized and is permanently mounted to the drivetrain.

Although we were not able to continue assembling the main drivetrain, we still got a lot done this week. We spent a lot of time working on the swerve modules and spent the beginning of the week assembling all Mk4is with L3+. We decided to go with this specific change to the swerve modules because it will increase our speed and changing the drive motors to Krakens it allows for a lot more power. However, after assembling all four modules at the beginning of the week and handing them off to electrical to wire, we realized that all the bearings on the swerves were not sealed. We diagnosed this by the squeaking of the wheels when they were rotated and it was making them a little harder to turn. We had an extra sealed bearing on hand and were able to switch out the bearings on one of the swerve modules, but are still waiting for our order to continue with the other 3 swerves.

The other big project that we worked on this week was the bumpers. This year we decided to make three sets of bumpers instead of two. This is so that we can use one for practice and not worry about damaging our actual bumpers. After receiving our parts we were able to assemble them all at once and duct tape our pool noodles to them. We are planning to wrap them in fabric next week.

We also have a new way of mounting our bumpers that is different from our previous year. We are using a bolt-like attachment on the bumpers that goes through the bumper gussets and is then secured on the other side by a nut. This design was shared last year by Citrus Circuits. Here is what it looks like in CAD (without the nuts):

Along with bumpers and swerve modules, we are continuing to work with electrical to CAD mounts and shields for the electrical parts. We also started designing new swerve shields this week, which will include our cameras in them.

Climber:

This week, Climber was getting a lot done, but not everything smoothly. There are some things I want to clarify from my post last week because some things might have been a little confusing. We will have two sets of climber’s arms this year, both are based on the same principle of a cantilever arm that rotates around a pivot point and is connected to a winch that holds it down while a torsion spring allows the arm to rotate up. The first set of arms, which we are calling the “Long Arms,” is designed to climb anywhere on the chain without needing to counterbalance themselves against the stage. The second set of arms, which we dubbed the “Short Arms,” are specifically for climbing to score in the trap. These will need to use our shooter to counterbalance to stay upright and score in the trap.

With that extra clarification, some things we got done this week include finishing fabricating the Long Arm and assembling it. We haven’t been able to put it on the robot yet, but we plan to integrate and assemble the robot this upcoming week. We also decided on a hook design that would work for us. We have also finished assembling the winch and attached it to the outer frame rails and the intake.

Some things that didn’t go as well were that somewhere between changing the hook, we forgot to shorten the aluminum tube that rotates with the hook at the end. Thankfully, we didn’t cut it too short, and if we had, we now know we can shorten it by the right amount. Some other problems we encountered were some of our 3D clamps breaking and the hooks being too heavy. To fix the 3D clamp problem, we had to rotate how we positioned the 3D print on the print bed to print nicer with no overhangs. We haven’t come up with a solution yet to lighten the hooks and the end of the rod, but if you have any suggestions, please feel free to comment them below.

Shooter:

As always with robotics and more specifically the shooter, the thing worked better in CAD. The actual subsystem is fine with only minor issues. One of the problems with the shot is that we draw too much power from both the flywheel motors and the kicker belts. We will fix this by compressing the note slightly less in the kicker setup by making the crowned pulleys smaller as well as continue to investigate the amount of current we are eating up just spinning the flywheels (probably the belt tension or something like that).

Another issue that may be more pressing is the overall structural soundness of the shooter. Due to some miss-tightened bolts in the pivot, the shooter leans around a ¼ inch to one side and can yaw and roll slightly. This is exacerbated by the loose mounting on the shooter to the frame. To combat this we are switching from tubes to mount the shooter to threaded aluminum blocks.

On the other hand, we have started to collect data for the speaker shot and we are 100% consistent from the subwoofer and the podium and our robot was not structurally sound enough to shoot from farther back.

Videos of the shots:
IMG_6109.mov
IMG_6110.mov

[gcschmit]

We’ve released 3061 Lib v2024.2.0. The full release notes are linked. We’ve fixed a few bugs and added a few features (lock rotation to speaker, physics sim classes to facilitate simulation with Phoenix 6 devices, and improved vision pose estimation). Please feel free to post in the discussion or file issues.

[angelajp7]

Week 7 & 8 Intake Updates

…where to begin…week 7 has been a very long week. Intake has been working through our major design changes. We finalized a CAD for the rollers,

before we realized quite possibly the second-worst news of the season (with the worst being the rollers not working). It’s that the transition doesn’t work. Not only does it not work, it fails spectacularly. The transition doesn’t work, the drum doesn’t work. So, we went into a whole-team flurry of prototyping. We tested transitioning (from rollers into drum), the drum (with powered wheels this time), and many other options. Here are all of the videos:
transition/drum testing 2/22

We walked away from this knowing that if we did choose to do a transition, it would have to be a complete redesign from our current design, it would have to be full of powered rollers (because the notes don’t like static surfaces), and it would take some time to design, CAD, fabricate, and assemble. Considering we only have NINE days until Heartland, we came up with some other options.

Those included our double intakes with a new transition, no transition (single intake direct to shooter), and a transition, but a larger drivetrain. After a few meetings, we decided that trying to completely start a new feature (the transition) in the few days we have until Heartland would not be worth it and we may reach a point where we don’t have a robot. To combat this, we decided to go with the single intake. We then laid a schedule for how to best fill our nine days until Heartland, in order to actually have a robot! We’ve redesigned the intake to mount to the shooter along with to handoff the note smoothly directly into the shooter.

Now, we’re just going to quickly get this design finalized, reviewed, and then fabricated!

Week 8:

This week, Intake has finished design changes, fabricated, assembled, wired, tested, and mounted our redesign! At the start of the week, we had a design, just in CAD, but at the end of the week, the Intake was running cycles on the robot, mounted to the drivetrain! If it’s not obvious, this is really good, and we’re moving in the right direction, finally! Now we fix some small issues we found when assembling, and build a new, [hopefully] perfect Intake to be ready for Heartland! 5 meetings left. Here’s our newest cad.

Here are some videos.

Intake collecting off drivetrain.MOV

First Note Collected.MOV

Running Intake cycles on drivetrain.MOV

However, we have run into a few issues. When we were reviewing the design, we realized that one of our gears was about .05 inches off of the carpet. Because the robot sinks into the carpet and the tread is squishy, this is an issue, as our gears would literally be in the carpet (big bad). Because we no longer have enough space to fit a pulley on that shaft, we’ve pivoted to using four smaller gears, (24t, 28t, 50t, 24t) to transfer the power between the rollers.

Throughout all of this, we’re really close to the motors on the swerve drives.

Due to not being able to fit normal gears, we are having machining cut down our gears, on the lathe, to only be 3/16” thick. This will introduce some issues with durability, however it is absolutely necessary to fit our Intake.

That’s it for Intake this week, and we’ll be back next week for one final update before we head off to Shawnee, Kansas for the Heartland Regional! We’re excited to see all the teams there, and see how our robot is able to perform on the field!