It’s been several long years since RoboWrestling has gone to competition, but the time has finally come. We’ll be presenting a high level overview of their robot, Kirbi, and covering Kirbii’s debut at Robogames 2023.

The RoboWrestling team was created to compete in autonomous sumo competitions, a specific brand of combat robotics in which small but mighty bots compete to push each other out of a metal ring, called a dohyo. For RoboJackets members who haven’t had a chance to watch a robot sumo match, it’s an intense race of speed and precision, and we recommend viewing the short video below for an overview. This year, RoboWrestling will be traveling to California to compete in the autonomous sumo division at RoboGames. This is the first year that sumo is back in the US after RoboGames 2019 was canceled, so this is an exciting opportunity for the team to experience a real competition environment!

The work over the past years on Kirbii has been subjected to highs and lows. The lack of competition over the past few years has stunted parts of the design process as well as knowledge transfer from previous team members. Despite the setbacks, the team has been working hard and is excited for competition. On the mechanical side, the goal was to make the robot as robust as possible. Sumo robots are subjected to strict size and weight restrictions, so the focus is on developing a competitive advantage while keeping in mind physical tradeoffs. The mechanical subteam prioritized a good blade, the key part of the robot that leverages up the opponent off the ring, and an arrangement of strong magnets on the bottom of the robot. Since the dohyo is made of steel, the array of magnets give Kirbii an effective weight of over 300 pounds, though the robot’s real mass is only 3 kg. The goal with Kirbii’s mechanical design is to drive the blade underneath opposing robots to reduce their hold on the field and drive them out of the ring. Likewise, the higher Kirbii’s effective weight is, the harder it will be for opponents to leverage the robot off of the field. The mechanical team has also built their own dohyo, which has enabled the team to test-drive their robots and gain more experience before competition.

The electrical subteam has also made several improvements to Kirbii’s design. The new electrical configuration uses one motor controller for both motors, as opposed to the previous design which had two separate motor controllers. The single Sabretooth motor controller has improved specifications like higher continuous amperage and consolidated control signals, which will help with robot operation and simplify the circuitry. Like its predecessors, Kirbii also uses a pair of distance sensors to find its opponent on the ring. The two sensors are multiplexed together before connecting to the teensy microcontroller. Overall, the mechanical and electrical foundations of Kirbii are solid and ready to compete.

The software team is responsible for the strategy that Kirbii employs at competition. With such quick match times and consistent environmental surroundings, simplicity is king. The team opted for a hunt-and-seek strategy, affectionately known as slammy whammy. The algorithm uses data from the distance sensors to determine the opponent’s location. Then, there’s a threshold for action defined by a minimum distance to the opponent plus agreement from the multiple distance sensors on the opponent’s location. Once this threshold is met, Kirbii launches its attack by going full speed to plow the opposing robot off the field.

The competition at RoboGames 2023 was small compared to previous years. There were a total of 3 robots present, including RoboJackets. Kirbii was able to win its first match against Turtlebot, a new competitor that did not employ magnets to increase its effective weight on the ring.

The other robot present was against the Kimauánisso Robotics Team from Brazil. They are tough competitors and consistently place high in any competition they attend. While Kirbii did lose to them to get second place, Kirbii did not go down without a fight and did get into pushing matches that led to a point reset. 

The main goal of this competition was to get as many team members on RoboWrestling experience in the competition environment. Although this was a smaller competition, the team hopes to be able to qualify for the All Japan Robot SumoTournament this December as the United States’ representative now that international teams are able to compete for the first time in four years. RoboJackets consistently attended this competition before the COVID pandemic. The team at RoboGames was a total of 12 members. Jason Katz, RW PM and now Vice President, emphasized:

As of now, there are no current members in RW who have been to comp, because our first year as an official team was 2020. Our last comp before [in 2019] everyone was on the way out graduating. … If we go to Japan, we’re not going to be able to bring 12 people, but we want the team to know what it’s like.

RoboWrestling as a whole is going through a rebuilding period after a long period of not being able to attend competition, first because of RoboGames’ cancellation, and then because of travel restrictions from the pandemic preventing international competition. Notably, Kirbii was designed before the current team started in RoboWrestling. To help with this transition, the team is considering going to smaller weight classes like 500 g to enable faster iteration, as 500 g sumo robots can be produced using exclusively 3D printed materials and do not use magnets on their wooden arena. In the future, the team hopes to use the 500 g robots as an experience for new members to find their footing, much like BattleBot’s 3lb program, while having more experienced members work on the larger bots. The team hopes this will allow them to bring more robots (and therefore, members) to RoboGames while still being able to compete at the highest level of competition in Japan.

President: Priyanka Rajan

Priyanka is a 3rd-year Computer Science major. She has been an active member of RoboJackets and has held various roles within the organization. Last year, she served as the RoboNav Project Manager, where she focused on establishing the team’s foundations for the University Rover Challenge (URC), the team’s new competition. She also previously worked as a RoboNav Software Developer.

One of Priyanka’s favorite experiences in RoboJackets was attending IGVC during her freshman year. Despite encountering microcontroller issues, she enjoyed working through the challenges with her team and appreciated the camaraderie they shared. Throughout her time in RoboJackets, Priyanka has gained valuable experience and made significant contributions. As the RoboNav Project Manager, she directed team progress, set goals, and organized the prototyping, building, and testing of a Mars rover robot from scratch. She also developed new recruitment strategies to expand the team and share robotics knowledge with more students.

With her extensive experience and passion for robotics, Priyanka is well-equipped to lead RoboJackets as its President. She is committed to fostering a supportive and collaborative atmosphere within the organization and looks forward to further advancing the club’s accomplishments. Priyanka values the people aspect of RoboJackets and is excited to continue building and fostering the community as the President.

Vice President: Jason Katz

Jason is a 4th-year Computer Engineering major and has been a part of RoboJackets for three years. In his previous role as RoboWrestling Project Manager, he tracked progress, set yearly/monthly goals, and conducted weekly check-ins to ensure the progress was being made, eventually leading the team to place 2nd overall at their first competition in over three years. Prior to this, he held the position of RoboWrestling Mechanical Sub-Team Lead from April 2021 to April 2022. In this role, he not only trained incoming members on the team’s design philosophy but also led projects focusing on the design of modules to be added to the robots.

Outside of RoboJackets, Jason gained industry experience as a Test Engineering Co-op at Annapolis Micro Systems, Inc. from May 2022 to November 2022. Here, he tested chassis, backplanes, and complex PCBs to ensure their proper functioning, which included verifying accurate clocking and communication between different components of the system.

Furthermore, Jason also worked as an Undergraduate Researcher at the Georgia Tech Research Institute from August 2021 to December 2021. In this role, he conducted research on supercapacitors, specifically characterizing commercial and lab-made supercapacitors through scanning electron microscopy and CV curve analysis.

Jason’s extensive experience in different roles within RoboJackets, as well as his industry and research experience, make him a valuable addition to the core leadership team. With his skills in design, project management, and testing, Jason is well-equipped to contribute to the success of RoboJackets and its future endeavors at Georgia Tech.

Secretary: Ryan Mak

Ryan is an incoming 2nd-year mechanical engineering major. He brings with him valuable experience from his participation in the 3lb program in BattleBots last year. In the program, Ryan worked on developing new 3lb robots called Stirfri and Feloni.

One of Ryan’s most cherished moments from his time with RoboJackets was when he had the opportunity to attend the State of Franklin Robot Rumble in Tennessee. This experience not only allowed him to showcase his skills but also gave him a deeper understanding of the robotics community. With this enhanced perspective, Ryan eagerly looks forward to organizing more RoboJackets events in the future.

Outside of school and robotics, Ryan has a diverse range of hobbies that keeps him engaged and active. He particularly enjoys activities like hiking, traveling, windsurfing, paddling, skiing, and swimming. These interests display his love for the outdoors and adventure.

As a true Yellow Jacket, Ryan is dedicated to his studies and determined to excel in his mechanical engineering program. By becoming a member of RoboJackets, he now has the platform to further enhance his skills and pursue his passion for robotics. With his enthusiasm, experience, and wide range of interests, Ryan is set to make a significant impact within RoboJackets.

Shop Manager: Michael McCabe

Michael is a 3rd year Mechanical Engineering major and is taking over the Shop Manager position in RoboJackets. He is a member of the RoboRacing mechanical subteam. Michael’s favorite experience in RoboJackets was attending the 2023 AKS competition and working with teammates to get their kart operational and navigating the track.

As shop manager, Michael plans to build upon past organizational work to increase the ease of retrieval for common tools and improve the flow of the shop. He is excited to contribute to the team’s success and help create a more efficient and productive workspace.

One of Michael’s fondest experiences at Georgia Tech was working on the capstone design project in Georgia Tech’s ME2110 Creative Decisions & Design class. The project focused on designing, manufacturing, and programming a fully autonomous robot based on the semester’s theme of Star Wars. Michael’s team, the Millennium Jackets, had the challenge of retrieving lightsabers, defeating Imperial Walkers, bringing Baby Yoda to safety, and destroying the Death Star.

Overall, Michael brings valuable experience and a passion for robotics to his role as the new Shop Manager in RoboJackets. His dedication to organization and continuous improvement will contribute to the success of the team and the overall advancement of robotics at Georgia Tech.

PR Chair: Leo Lam

Leo is an incoming 2nd-year mechanical engineering major. His passion for robotics led him to join RoboJackets, where he has quickly become an integral part of the team. Last year, Leo participated in the 3lb program in BattleBots, working on a new robot called Scampi. This experience allowed him to gain valuable hands-on knowledge in building and operating robots. Currently, Leo is excitedly working on Anxietii, the second iteration of the 30lb robot. One of Leo’s favorite experiences in RoboJackets so far has been the in-house 3lb scrimmage. It was during this event that Scampi achieved its first win, a memorable moment for Leo and the team.

Leo developed graphic design skills by building logos for an online Pokémon Draft League, creating Twitch overlays and designing mall signage for Rumi Life.  As the PR Chair of RoboJackets, he hopes to utilize these skills to expand the organization’s reach and foster greater interaction within the community. With his dedication and expertise, Leo is poised to make a significant impact in RoboJackets.

Outreach Chair: Ishan Doma

Ishan is a 4th-year Biomedical Engineering major. In terms of his research experience, Ishan has worked as a Research Assistant at the Roy Lab and the Kamaleswaran Lab. In these positions, he has been involved in investigating the efficiency of cell manufacturing processes and the use of machine learning algorithms in processing live patient signal data.

In terms of extracurricular positions, Ishan has served as a Prototyping Instructor at the Invention Studio and has been involved in research projects at the Roy and Kamaleswaran labs. Additionally, Ishan has held leadership positions in organizations such as GT Student Foundation Developments Committee and First-Year Leadership Initiative (FLI) Alumni. Furthermore, Ishan is also a member of the Origami Club Executive Board and has served as an Undergraduate Research Ambassador and SHS Ambassadors Finance Officer.

Ishan previously served as the Mechanical Training Lead and the lead of the RoboCup Mechatronics subteam. 

In terms of volunteer experience, Ishan has been actively involved in various organizations. He has served as a Blood Donor Ambassador for the American Red Cross for the past four years. Additionally, he has volunteered as an INOVA Physical Therapy volunteer at Inova Health System for nine months, as well as a Volunteer at Reston Hospital for almost two years.

With his strong background in biomedical engineering, research experience, and passion for outreach, Ishan is well-equipped to make a significant impact as the new Officer for Outreach in RoboJackets at Georgia Tech. His dedication to both his studies and extracurricular activities demonstrates his commitment to advancing the field of robotics and helping others in the community.

This year for the first time, the RoboJackets BattleBots team competed in the National Havoc Robot League (NHRL). The NHRL was chosen as an alternative to the much-beloved Motorama as BattleBots’s new yearly “big bots” competition. Four bot teams traveled to NHRL in Norwalk, CT to compete — three 30-lbers (Chonkiii, Anxieti, and Tsunami) and one 12-lber (Hockii). For a refresher on the bot designs and weaponry, read our previous BattleBots overview or our special article on Hockii. As always, the competition was an exciting chance to test the engineering design, manufacturing, and iteration done by the team over the past year. 

NHRL is a unique competition league consisting of six qualifying tournaments, held throughout the year, and a world championship in November. NHRL is the largest combat robotics league in the world, and also one of the few that field both 12 lbers and 30 lbers, so there are some fierce competitors. The league structure also means there are several potential competitions, held throughout the summer, for the teams’ robots to enter. The RoboJackets team ended up attending two of these qualifying tournaments— one in March and one in June.

During the March tournament, Anxieti, the 30-lb undercutter, was able to win three matches and reach third place overall in the qualifying bracket. This means that Anxieti and the bot team are qualified to attend the NHRL World Championships in November. You can watch a few of Anxieti’s matches here: Anxieti vs. SAKE SCHTROVN (W), Anxieti vs. Floor Letter Word (W), and Anxieti vs. STF (L). Chonkiii and Tsunami also had good showings, going 2-1 and 1-2 respectively. Hockii is a more experimental bot, but the team still made good progress since last year. All of the bot matches can be seen in the NHRL livestream linked above. Overall, 2022-2023 BattleBots EPM Brian Naing had this to say about the March NHRL event:

“…it was a really cool competition that was focused on providing the builders the best possible experience. I think the teams also mostly enjoyed having more competitive success this year and are more motivated going into next year.”

With the success seen at this tournament, the BattleBots team decided to iterate on Anxieti, Tsunami, and Chonkiii next year and implement the improvements needed based on their tournament performance.

But the year wasn’t over yet! Bolstered by a good showing at the March tournament, the Chonkiii and Tsunami teams decided to attend the June qualifying tournament as well. The competition was fierce, with many nationally top ranked robots attending, as well as competitors traveling in from the UK. Chonkiii, the 30 lb shell-spinning shuffler, fought against the #3 nationally ranked robot, Yahoo, and won its match to earn a #2 tournament seeding; watch the match here. It’s an exciting one, with several big hits, Chonkiii looking very strong, and a tap out from Yahoo at the end. Tsunami, the 30 lb beater bar, also performed well in its matches: Tsunami vs. PanjandruM (W), Tsunami vs. Agent P (W). Unfortunately, both Chonkiii and Tsunami ended up encountering electrical or mechanical issues that prevented them from continuing to fight the good fight. With such a great showing, though, the team is certain to see success in the upcoming year.

The new BattleBots PM for 2023-2024, Siva Appana, had this to say about the June NHRL experience:

“Both teams had an excellent time fighting and repairing their robots for each fight. They were even able to assist other teams with their issues, embellishing the BattleBots community. We look forward to participating more in the general BattleBots community and are excited to see how our robots perform this year.”

Overall, NHRL was a great experience learning and growing for the BattleBots team, and RoboJackets is excited to see more from Anxieti this November.

The team video highlights current robot performance. It requires at least one minute of unedited game play with at least two robots participating in shooting on a goalie, going for ball capture, or movement against static defenders. 

With both the video and paper submitted back in January, the team heard back recently that they have qualified for RoboCup 2023! This will be the first time they attend an in-person competition since 2019. They will be headed to Bordeaux, France this summer. If you are interested in watching the team video, it is linked here. 

Megan Huang, the RoboRacing project manager, has been involved in the planning of this new competition. Every other week, she meets with representatives from other EVGP teams to discuss rulesets and logistics. The competition was renamed as the Autonomous Karting Series (AKS), and it will be held on May 15-19. Purdue Autonomous Motorsports have reserved the original evGP Autonomous track as an independent club, and a website for AKS is now under construction. Since the competition is now organized independently of evGP, individual teams have more of a say in the details and logistics. 

We’re happy to see the efforts from RoboJackets in preserving this unique competitive forum. As Megan said, “There are competitions centered around building a go kart and competitions centered around automating pre-made vehicles, but it is difficult to find competitions like evGP Autonomous that combine both aspects… [this is] why I am so interested in the continuation of this competition. It brings a lot of space for people in mechanical, electrical, and software disciplines to learn.” Hopefully, with the leadership from RoboRacing and all the other teams from EVGP Autonomous, AKS will have a successful inaugural year.

Internally, RoboJackets made some changes to how the organization organizes the event. In the past, Kickoff has been coordinated by a single appointed officer, the Kickoff Coordinator. This year, in recognition of the importance of the event to the community and the amount of work required, the position was split into a small committee of three members, one 4th year and two 2nd years. This year’s Committee was Shishir Pandit-Rao, Abhiram Ghanta, and Yashas Ambati. In addition to the work distribution, there is also a knowledge transfer component. Shishir said: “by developing this committee approach, we hope to maintain better knowledge transfer to ensure this event is run smoothly for years to come!”

One change this year was holding the workshops before the presentations instead of after, as they had been in the past. This was done in response to feedback from attendees that the teams wanted more time during the day, and allowed teams to start on designs immediately after the game was revealed instead of having to split up to go to workshops. 

RoboJackets hosted three workshops, one for each major discipline in FRC: Mechanical, Electrical, and Software. Notably, this year had much higher workshop participation than past years, between 40-70 attendees in each workshop, compared to 10-20 in previous years. Abhiram Ghanta attributed this to the fact that the workshops were held before the kickoff broadcast. In addition to these workshops, there are workshops that are related to the specifics of the game that were moved to a virtual format to be hosted by Georgia FIRST a week after kickoff.

Shishir was proud of the event overall:

This year’s FIRST Robotics Competition Kickoff event was an astounding success! With over 60 teams and 500+ registered attendees, this event is growing year by year, allowing students to get the first glimpse of the game in a collaborative space with other teams, as well as allowing students to develop knowledge with our technical workshops.

By using a drone to complete this portion of the competition, the RovoNav team can avoid terrain-related traversability challenges and reduce the weight of the rover. The mechanical team can simplify the rover’s design and sensor load, and instead focus on designing and manufacturing other complex structures such as the arm, end effector, chassis, and soil sampling subsystem. The software team chose a prefabricated drone (the VOXL m500) and is building the flight software using PX4 and ROS2. 

To ensure a safe landing, the team will use a map interface to select and feed the drone “good” coordinates in the vicinity of the autonav gates. The gates progressively increase in traversability difficulty from the first to the last (eighth) gate, and the drone will take the unusual strategy of navigating from gate 8 to 1, essentially completing the course backwards. The software team plans to use this strategy to have the gates with the most treacherous surrounding terrain completed by the drone. Since the drone cannot complete the course on one battery charge after accounting for payload, the rover will then complete the course by moving through the remaining easy-to-access gates in the normal order, from gate 1 to wherever the drone stopped. In this unique and piecewise way, the team hopes to complete the course successfully and surpass other teams in the competition.

A small contingent of RoboJackets set up a table with posters and example robots to let the wider community know what kinds of robotics projects are out there, and also were introduced during a timeout.

Zach Slaton, President, was present and said “Tabling at the basketball game gave us some great publicity to people we wouldn’t normally meet, and we were especially popular with kids. We gave out a lot of stickers, and we hope we inspired some future RoboJackets!”

The 12-pound Hockii is a type of combat robot known as a “meltybrain”, which uses its drive to spin and hit opponents with the entire body [read more about the previous iteration here]. After last year’s competition, the team noticed that the weapon tooth was a major weakness. Additionally, the fact that it was integrated with the frame meant it was impossible to replace. Thus the team aimed to make a tooth that was both stronger and replaceable. 

Mounting the tooth to the frame introduces additional challenges. An improperly-designed tooth or joint would result in the fasteners breaking and the robot ending up toothless. Hockii’s new tooth slots into the frame to help direct moment loads into the shell, while two large bolts keep it in place.

Team member Martha Leach took the tooth design to the next step. Through her internship at the Mayo Clinic Division of Engineering, she had the opportunity to research and utilize computational design and additive manufacturing tools. She led the team to develop experimental teeth which leverage two unique techniques: topology optimization and generative design. 

Topology optimization is a computational technique where a model is iteratively modified to minimize an objective while still meeting a target constraint. In this case, the model was optimized to reduce material while still being able to withstand the load of impact. 

Generative design is a newer technique where a designer starts by inputting constraints and features of a part. The software then explores the design space to generate multiple possible parts which satisfy the prescribed constraints.

These two teeth were then printed out of titanium using the Selective Laser Melting (SLM) printing process. The teeth are pictured below. 

The team behind Hockii is hard at work preparing all robot systems for the March NHRL competition and hopes to put these new teeth to the test against some of the top 12lb combat robots in the nation. 

When the team first began evGP, a few hardware components were required as part of the rules to be standardized across the robots. Some of those components included a specific Top Kart frame, batteries, and motor component combination. This was originally to give equal footing to new competitors and allowed for the teams to focus on a reduced quantity of components and systems not specified by the rules.

For the drive system, all of the teams were required to use a brushed motor (ME0708) with a golf-cart motor controller (SR48300) and an optional reversing contractor (SW202). Using current sensors, encoders, and practical application of Georgia Tech controls classes, the team was able to compete in two evGP competitions with the drive system. However, there were some control bugs with the golf-cart motor controller. This caused “interesting” events like the robot unexpectedly driving forwards / backwards and low speed control resulting in the car starting and stopping constantly. Additionally, talks in the competition planning had resulted in the expansion of possible drive systems, specifically using brushless motors. 

Brushed style motors, as was originally on the robot, were some of the most widely used motors for many years in industrial automation. They were very easy to actuate with only a voltage potential being applied across the two wires and are still very often found in cheap toys because of the simplicity. Brushless motors, in comparison, have three wires that need specific timing to turn on and off in a pattern, with this added complexity limiting adoption in smaller scale / hobbyist applications. Brushless motors have since exploded in popularity and availability due to more efficient energy/weight ratio and longer lifetime compared to brushed motors.

This combination of factors has led the team to switch to a new brushless motor (Golden Motor HPM5000B) and motor controller (VESC 75/300R3) for actuating the drive system. The new VESC controller includes the capabilities to measure current and voltage along with customizable filters, proving much more sophisticated than the original motor controller and allowing for more tightly integrated speed control. The new system also allows for the removal of the reversing contactor, which was heavy and generated lots of heat in the closed enclosure, while maintaining the reversing ability. RPM control has been proven with the motor and controller, with additional development required for full robot drive control.