Last August, the very first RoboJackets alumni newsletter was sent out. Since then, it’s been a great year of monthly stories, team updates, and member features. We’d like to take a look back at the start of the alumni newsletter and the past issues created by the newsletter team.

The discussion around how to best serve RoboJackets alumni is no stranger to the organization, and some first steps to implementing a real structure for alumni involvement were taken in 2019 and early 2020. Around this time, there was a critical mass of alumni who were still active and involved in RoboJackets. These alumni began having stakeholder meetings with current leadership to work towards the incorporation of RoboJackets, which was the most pressing need at the time; these meetings would later be formalized into RoboJackets, Inc. corporate meetings and the RoboJackets alumni association. A secondary outcome of these meetings was the more general question of what alumni can do for the organization, and vice versa. Since Motorama had just occurred, the idea of an alumni newsletter to report on competitions, progress within RoboJackets, and general organization happenings was proposed. 

From this initial proposal, the RJ President, Vice President, and PR Chair (Joe Spall, James Reed, and Vijay Srivastava) at the time took steps to outline more specific goals for the alumni newsletter and consolidate our previously unorganized lists of alumni contacts and business cards. Other early discussions included which topics alumni would be interested in, whether to include sponsors on the newsletter, and how to promote the newsletter on our social media platforms. That work provided a solid foundation for the next core officers (Alex Field, Ava Thrasher, and Cameron Loyd) to recruit alumni writers, solidify content plans, and design the first newsletter, which was eventually sent in August 2020. From there, it’s been a constant flow of brainstorming and content creation to send a monthly, hopefully engaging email to our growing audience of alumni and friends and family. A secondary goal of the newsletter team was to ensure the longevity of this project, and to do so the writing and publishing process was well-defined and documented throughout the year. Most recently, management of the newsletter was successfully handed over to the 2021 core officer team (Shishir Pandit-Rao, Tan Gemicioglu, and Shail Patel), which shows that the project can change hands and thrive for many years to come.

To get more of a personal insight into the newsletter writing process, we asked Jonathan Spalten, an alumni writer who nearly single-handedly kicked off the newsletter, and Alex Field, one of the members of the founding core officer team, what they thought of when looking back on a year of newsletters. Jonathan stated: “Writing for the newsletter has been a great opportunity to provide some extra support to the organization even after graduation. Because of how we write the newsletter, it gives me the opportunity to get a glimpse into what’s still going on [in] the club, which I hope gets translated down into the articles we write to let other alumni have that same opportunity.” He also mentioned that his favorite articles to write have been the recent alumni spotlights, as it allows him “to check in with some alumni we haven’t heard from in a while, and also to hear their perspective on how RJ still influences them in their professional lives.” Alex had similar thoughts on the importance of the newsletter, saying that alumni are “members just like the students currently in the organization. Once a member, always a member. The newsletter allows us to involve every single member with our teams and projects, whether they are with us currently and away at whatever great career and future they are leading.” He pointed to motivation and overall growth as the most critical factor for keeping the newsletter going. “As we continue each year, our graduating classes will be able to take part, increasing those numbers which will make our writers even more motivated to work hard. The challenge has always been, “How can we push through these tough early stages and keep a consistent stream of high quality content?”…[W]ith the rejuvenated interest we have received from the alumni and the newly found alumni association, we have the needed support to keep going strong while preventing our [current] leaders from feeling too overwhelmed.”

Overall, we hope to see the alumni newsletter continue to progress in the coming months and years. It’s a labor of love for us communication-challenged engineering students. It’s taken the effort of nearly all current RoboJackets leadership and a dedicated and talented team of alumni to get us to this point. The framework and goals set up over the past two years will continue to evolve, and we hope to see the audience of the newsletter grow as we retain alumni contacts and improve our content. If you have any feedback or comments for our newsletter team as we begin our second year of issues, please fill out this form and feel free to share our subscription link (news.robojackets.org) with any other RJ alumni, friends, or family you think would be interested! Also, if you’re an alumnus with a passion for writing who would like to get involved in the newsletter pipeline, reach out to Tan Gemicioglu via Slack or email to learn more; we’d love to have you!

The main challenge of combat robots is designing and manufacturing a robust robot that can withstand the trials and tribulations of repeated contact with enemy robots and being flung around the combat arena, while budgeting weight to ensure they meet the weight limit imposed by their weight class. This challenge has to be kept in mind for every aspect of the combat robot. This includes the electrical system, the central system that enables the combat robot to work. To support this, combat robots usually have a simple, streamlined system of electronics. This electrical system is the focus of this article.

Most combat robots consist of two major subsystems: the drive train and the weapon system. These systems have two main components in common: the battery and the radio receiver. A typical combat robot utilizes a Lithium Polymer (LiPo) battery, notably used in a variety of applications that require a lightweight power source. LiPos have one of the highest energy densities of modern batteries, which makes them a logical choice for any application where weight is a concern. For smaller combat robots, it’s typical to use a single battery pack, but for larger robots, often two or more separate batteries provide power for the drive system and weapon system, often because the two operate at different voltages to better suit the higher speed motors used for weapon systems. Voltages are usually specified in terms of how many cells the LiPo battery has, with 3.7 V nominal per cell. A common voltage in many weight classes is 3s (11.1 V nominal), but some higher weight class robots can go up to 6 to 8s (22.2 and 29.6 V nominal) for their weapon systems to enable their weapon motors to go at high speeds and run at lower currents for the same amount of power.

The other major shared subsystem is the radio receiver. This takes in the signals sent from the remote controller that the operator uses and sends signals to the controllers within the robot that operate the weapon and drive systems. RoboJackets’ combat robots often use a simple 4 channel receiver as a tried and true controller that works for the vast majority of robots.

The next major components are the motors and motor controllers. These are what turn the signals that are sent from the receiver into motion. The motor controllers are often the major failure point of many combat robots, so great care is taken to ensure that they are well protected inside the robot, to prevent damage, as well as ensuring that their specifications are adequate to handle the voltage and amperage that robot robot motors need to run. This is where the types and typical specifications diverge wildly. Different robots have different needs for their motors, and the motor is what defines what the requirements are for a motor controller, often abbreviated to ESC, for electronic speed control. These requirements are mainly required voltage and current, but can have other requirements, such as whether the controller can run a motor in forward or reverse without changing the wiring. For most drive motors, RoboJackets and many other combat roboticists use brushed motors for the drive system because of their robustness and simplicity. They also typically have less demanding speed requirements than weapons. The speed requirements for weapons usually necessitate a brushless motor that is capable of higher speeds. 

There are many specifications that go into a brushless motor that need to be considered and depend on the requirements for the weapon system. For example, a robot that spins a larger weapon, E.G. a shell spinner, will require a motor that can deliver higher torque to enable a faster spin-up, minimizing the time before they can damage the enemy. Additionally, they may not need as much rotational speed to deliver large forces because of the sheer mass of their weapon. A robot with a smaller weapon, such as a bar spinner, does not need as much torque to accelerate their weapon, but will want to achieve a higher speed to deliver as much force as possible. For drive motors, there are motor controllers that can control two motors in one board and handle the programming to turn the robot with simpler inputs. These boards are typically larger, but they are often used on 3 lb combat robots because of their simplicity.

This, however, is not the be-all-and-end-all of combat robot electronics. There are opportunities for RoboJackets to delve deeper into the electronics side of combat robotics. RoboJackets usually uses commercially available electronics from sources like HobbyKing and Scorpion Power Systems, but there have been discussions in RoboJackets about developing a RoboJackets motor controller that can better meet our specifications and build in other useful features, such as current control that could prevent accidental ESC burnouts, a common electrical failure. Additionally, last year the team developed a design for a “melty-brain” combat robot, Hocki, which constantly rotates and varies the speed between its two drive motors to make the robot translate in addition to rotate. It has some additional components that enable it to ascertain its rotational position and identify a given direction as “forward.” These represent new steps in delving deeper into the electrical systems of combat robots made by RoboJackets. In general, the system RoboJackets uses is simple and robust, and has room to grow and provide new useful functions that protect the components from electrical failures that can often cost a combat robot a win in a match.

Once again, we’d like to shine the spotlight on another alumnus this month to check in after their time at RoboJackets and Georgia Tech, and see where they are now and what part of RoboJackets they brought with them. This month, we’ll be featuring Aman More. Aman completed a B.S. in Mechanical Engineering at Georgia Tech in 2018. During his time in RoboJackets, he was involved in the BattleBots and RoboCup subteams, but drifted towards BattleBots over time. He built Smitti Werberjagermanjensen, the 3lb ring spinner. He, Cory, and Dustin worked on that robot together and wound up deciding to share an on-campus apartment soon after. This was just the beginning of his RoboJackets journey: 

Soon after that, I found myself getting more involved in the planning and support roles than actively leading any projects. I helped reorganize and update the Battlebots pages of the Wiki, and worked with then-PM Ryan Martin in drafting the plan for the 3lb Czar and mentors system. While I was originally a mentor, I found myself thrust into more of a leading role in the spring semester when the elected Czar stepped away from BattleBots.

Aman says the role he best fit into was “the guy who tried to help build the memes and community in BattleBots, helping everyone in the team feel involved and included in whatever was going on.” In particular, he emphasized helping new members connect with older members through those memes. He also says: “I took my role as the person who taught the new members about our long-running memes quite seriously.”

Now, Aman is in Germany, pursuing a Masters in Management and Engineering at RWTH Aachen University. He decided to pursue his Masters after about a year and a half of work in India at his family’s chemicals and engineering company: “I felt I would be able to contribute better if I had a better grasp on the business side of things, and decided to go back to school to learn how to bridge the gap between my technical background from Tech and RJ, and the managerial stuff.” In terms of hobbies, Aman cycles between videogames, self-taught coding, and 3D printing. He also has a passion for LEGO. Pictured below is the new shelf he had to get made in Mumbai just to store his new sets.

We also asked Aman what lessons he thought he learned during his time at RoboJackets, and how they helped him after graduation. He had three he wanted to highlight: experience in the full process from concept to manufactured product, practical design and CAD experience, and, finally, some direction on his passion beyond tech. He says: “RJ was one of the first few places where I actually got to follow the full process of designing and building something from scratch. … Being able to visualize how a part I was designing could be manufactured in the next stages has been invaluable to me, and a large part of that ability came due to my experience doing that at RoboJackets.” He was also able to develop a system of sketching and CAD work that greatly helped him communicate designs to people he’s working with. On his passion, he says:

Coming into Tech, I still wasn’t completely sure about what part of engineering I was most interested in, and I feel it was at RoboJackets where it all finally clicked, and I started my journey towards design and management of design teams. In some ways, you could say that the only reason I am doing my Masters program right now is because the planning/support roles I had in BattleBots made me realize that this is what made me happy.

Finally, we asked him what his favorite memory from RoboJackets was. As usual, it was a hard choice given his wide experiences of technical and meme proliferation work, but he picked his first Motorama:

It wasn’t my first robotics competition – I had done a fair few in high school – but the entire experience of the 14-hour road trip in a cramped van with boxes of robots that we (at best) half-expected would work was new to me. We had poured about 5 months into making these robots, and we didn’t expect any of them to get out of there in one piece. We weren’t worried about them breaking and catching fire; we were looking forward to it. It was a hectic few days, in the best way possible. As a side note, I think that trip was also where Cory, Dustin, and I decided to become roommates going forward.

RoboCup 2021 took place from June 21st to the 27th this year. After several hard fought matches, RoboJackets placed third in the lower tournament, a major highlight of which was a match where our team won 10-0. The competition started with a series of regulation games before moving to an upper and lower bracket that was decided in a double elimination format. Since the event was held remotely, the Small Size League in which our team participates staged matches by having competing teams upload the most recent version of their code to a server that would then play out the match virtually. 

The team encountered many challenges with their codebase during the competition. Some were minor and procedural – for example, connecting to the servers or updating the code to match the virtual format – while others were fundamental issues, a result of the software team lacking time to do adequate testing. This had major repercussions during the competition. For example – “[The virtual fleet] had issues with crashing into other robots so we would constantly get yellow/red carded”, said project manager Alyssa Gordon. However, members rallied to rewrite code as the competition progressed, and thus the fleet “went from not being able to score on a no-show opponent in prelims to winning a game 10-0 later in the knockout stages”, according to software subteam lead Kevin Fu. 

Rewriting plays on the fly resulted in some interesting problem solving. The fleet was having a lot of issues with double-touching the ball – a move where the same bot touches the ball and then kicks it. Double touching is illegal –  since the game is non-contact, being allowed to touch the ball more than once would mean bots could easily dribble across the field unimpeded. Said Fu: “Our fix was to line-kick the ball every time; meaning instead of dribbling and turning before a kick, we’d just drive up to the ball at the right angle and kick it.” While this reduced double touching violations, some scored goals were invalidated for exceeding the maximum allowed kick speed. Another improvised solution was the team’s offensive strategy – to compensate for a failing passing system, the bots would simply kick the ball hard toward the goal with the hope to score.

Regarding takeaways from the competition, Fu said: “[This year’s competition] made us realize that winning Div B is attainable and that we should be using a lot of standardized tools that the league provides.” He also said that, given that this is the first RoboCup competition he’s attended, he now has a better understanding of how the competition works and a lot of ideas for how to improve the fleet for next year. Some of those ideas include moving to the competition provided simulator to increase the accuracy of their testing, refactoring the codebase to be more maintainable, and taking a more agile approach to the team’s development process.

In order to allow teams to showcase their physical robots, the competition also had an optional hardware challenge composed of 4 tasks. These included scoring against static defenders, scoring against a defender that starts in contact with the ball, dribbling through static components, and passing. Unfortunately, due to a slew of issues that arose in the week leading up to the competition, the team had to drop out of the hardware challenge. Prior to the full assembly of the bots, the team was testing individual functionalities, but ran out of time to do more thorough testing with the entire system. When asked about the challenges they ran into, electrical lead Bernardo Perez discussed the impact of COVID on the team’s productivity: “ limited shop capacity made it difficult to get everyone into the shop… As a result, we were a little behind in testing the electrical stack.” The team had to patch their firmware two weeks before the competition; due to the previously mentioned constraints they were unable to thoroughly test it in time. Additional issues that occurred during competition included unstable radio connections and a malfunctioning inertial measurement units. Looking forward, the team plans to redesign the boards prone to malfunctioning, including the breakbeam board, which detects when the bot has possession of the ball. They also plan to do more testing to isolate the root causes of other malfunctions they experienced during the competition.

On the mechatronics side, subteam lead Dan Lam cited pain points in putting together and taking apart the bots as contributors to the team’s hardware issues: “a lot of the troubleshooting … was made much worse and prolonged due to the packaging of our platform… clearances with the boards and the inside of the shell made it extremely difficult to access all boards, battery, radio, etc.”  When asked about future plans for hardware, Lam stated that he’s hoping to “have more planning done with electrical, and work alongside them to create a more cohesive bot.” He also said he’d like to improve the bots’ shells and packaging, arranging “components… in a way that’s easy and simple to access, maintain, and troubleshoot.” 

Despite all of the challenges they had to overcome, the RoboCup team is in high spirits after their 3rd place win in the lower division. “I’m very proud of our team, and especially thankful for our software members who stayed up very late the entire week to continuously work on our code,” stated Gordon. 

Congratulations to the team, and we’re excited for what they’ll accomplish for next year’s competition! 

Tournament results and recordings of the matches can be viewed at https://ssl.robocup.org/rc2021/.