Game Strategy and Scoring Analysis 2022 Season

The first major topic we discussed in our brainstorming session was a review of the game rules and scoring elements. This review helps the team determine what elements to focus on in order to score as many points as possible in the match. During this time, it is also important to determine how to earn the additional ranking points in a feasible manner, as ranking points vastly help the team during qualifications. Using these two main topics, along with a discussion of our time and team resources, we developed a full strategy for our robot design.

Scoring Summary:

First, let’s discuss cargo, this year’s game element. There are 22 cargo elements, 11 for each alliance. Each robot can carry up to two cargo elements, regardless of color, and may begin the match with one cargo of their color pre-loaded into their robot. Any cargo not pre-loaded is staged between the opponent’s alliance wall and adjacent cargo line. The remaining cargo elements are as follows: 6 of each color staged on cargo rings around the hub, 1 alliance colored cargo in front of the terminal and one in a cargo ring in the terminal. During autonomous, cargo can be scored in the lower hub for 2 points or in the upper hub for 4 points. During tele-op, these values are reduced to 1 and 2 respectively. Teams can also score points by climbing the rungs in the hangar. The low rung is worth 4 points, mid rung is worth 6 points, high rung is worth 10 points, and traversing (or climbing) all the rungs is worth 15 points.

Let’s take a deeper dive at analyzing cargo; just how much is 11 cargo per alliance? For comparison, I will draw on the 2016 FRC game, FIRST Stronghold. This game featured 18 boulders, the ball game element for that year, and limited robots to only influencing one boulder at once. These boulders could be scored for points by either team, unlike this year’s game where teams only earn points for their colored cargo elements. If we assume each team “controlled” half of the boulders at any given time, then each team had nine boulders to score with, or 3 boulders for each robot. For this year, it would likely be reasonable to assume that two of your cargo would be out of your alliance’s reach due to either being picked up by the opposing alliance or by being defended by an opposing robot. Therefore, your alliance only has nine cargo in favorable positions, or three cargo in favorable positions per robot on the alliance. This is the equivalent of 1.5 sets of cargo per robot. Compared to some previous games, this is a lower number of game pieces per robot, which could contribute to a longer time of collection.

Now, we need to look into the hangar scoring in more detail. The first thing to consider is whether or not going for the rungs is worth it from a strategic point of view. In other words, would it be more beneficial to ignore the rungs entirely and attempt to score cargo in the remaining time? The most straight-forward way of determining this is finding the points per second scored on the rungs and comparing it to the points scored per second of the cargo. For example, if we estimate it will take 25 seconds to score the high rung, then our team would earn .4 points per second. Similarly, if we estimate we can score one cargo in the upper hub every 10 seconds, then our team would be predicted to earn .2 points per second. The time estimates you use in this section should be a reflection of your team’s beliefs based upon prior experience and other factors. However, even if we assume scoring one cargo in the upper hub every 7 seconds, it is still more beneficial in terms of pure points-per-second to climb the rung; a successful traversal rung climb would yield 15 points, or the equivalent of 7.5 high goals, which would likely take a significantly longer time for teams to achieve. Even with a shooter accuracy of 100% for the high goal, the amount of distance needed to travel to collect 7-8 cargo elements of your alliance’s color, would be significant.

Additional Ranking Points:

There are two ways to earn additional ranking points which should be considered in addition to the pure points value associated with scoring of the game elements. The first additional ranking point can be earned through scoring a total of 20 cargo into the hub throughout the match.  It is possible to reduce this number to 18 cargo if five or more cargo is scored during the autonomous period. Assuming that, on average, each team is able to score one cargo into the hub in autonomous, this leaves 17 cargo to be scored in the tele-op period, which is approximately 5-6 cargo per team, or three batches of two cargo per team. The fastest way to retrieve additional cargo is likely through either of the two terminals; however, the only way to get cargo to the human players at the terminal is through the cargo delivery openings. Using the cargo delivery openings would greatly extend the time it takes to score cargo. The other option is through direct pick-up of cargo from the floor, a large majority of which will likely be near the hub. Having a floor pick-up mechanism that quickly brings the cargo into your control is going to be one of the most important factors for this year’s game. Revisiting our ideas of 5-6 cargo scored per team, this number will be fairly substantial for many teams to achieve consistently. All six robots will likely be centralized around the hub in order to get cargo that has been returned to the field after scoring, leading to crowding and difficulty manipulating the cargo game pieces. Even robots that prefer to shoot from the protected launch pad could easily find themselves blocked by opponents or denied cargo, further increasing the time to score a batch of cargo. On the other hand, robots that tend to score batches of cargo into the lower hub may be at a significant advantage in terms of cargo-per-minute and quite possibly in terms of points-per-minute.

The second way to earn an additional ranking point is by scoring 16 points from the rungs in your hangar zone at the end of the match. The low rung and mid rung are at heights such that the robot can reach with a mechanism while staying on the ground (the low rung is at 4ft. ¾in., the mid rung is at 5ft. ¼ in., while the max height of the robot is 5ft. 6in while its bumpers are in the hangar zone). This will greatly lower the complexity of teams to achieve a successful climb. By using a one stage element as well, this can likely be achieved very quickly (5-10 seconds or even less) and consistently. With the mid rung worth six points, and the lower rung worth 4 points, the additional ranking point could be achieved with two robots on the mid rung and a third on the lower rung. Previous FRC challenges including Ultimate Ascent (2013), FIRST Stronghold (2016), FIRST Power Up (2018), and Infinite Recharge (2020) feature similar rung mechanisms for reference. While this would be a simple solution, there will likely be a significant number of matches where one of your alliance partners will not be able to climb. This would stop this method from earning the ranking point and will require a robot to be on the high or traversal rung in order to earn this rank.

Our Strategy:

After outlining the above ideas in our strategy meeting, the first topic we discussed was the goals for the rung climber. From the points analysis related to the hangar, we determined that it would be meaningful to pursue climbing to at least the mid rung. The mid rung offers six points, which we believe would be a greater number of points than what we would earn from attempting to score cargo in the same time. As well, we would have the potential of earning the additional ranking point, providing our two alliance partners could do the same or one could reach the high rung. We also believe that reaching the high rung and the traversal rung are both significant achievements that would greatly increase your chance of winning the match and of receiving the additional ranking point; a robot who scored no points during tele-op except for a traversal rung at the end of the match would still provide a significant number of points, likely more than some robots who scored cargo during all of tele-op. Therefore, we set this as a stretch goal for us that we will pursue if we have the time and resources in our event.

The next main topic we discussed was scoring in the lower hub vs. scoring in the upper hub. Clearly, the upper hub could provide twice as many points as the lower hub, if we assume that we could score with a high accuracy. This assumption would also only be the case if we attempt shots in the upper hub as frequently as we believe we could score in the lower hub.  As previously discussed, we believe that it will be substantially quicker to score in the lower hub than in the higher hub. Therefore, we would likely only be able to score marginally more points by aiming for the upper hub than if we aimed for the lower hub. This difference in points was not enough for our team to justify the extra time and resources towards the high goal shooter. (Although, it may be for a team with more experience and time.) As well, by aiming towards the lower hub we believe we would be more impactful in our team’s contribution towards the additional ranking points from scoring cargo.