Introduction to the NHRL Open 2025 Ruleset

Thank you for your patience competitors! We are pleased to announce the release of the Spirit of the Rules, Builder Conduct Policy, and Design Rules for the NHRL Open 2025 Season.

This has been the largest and deepest reexamination of the NHRL rule-set since the organization was first formed. NHRL has completely revamped how rules are evaluated and how rules changes are handled, and we hope this better serves NHRL and the NHRL community at large moving forward. We have included this preface to better explain how and why changes are being made, and to add context that may not be fully apparent in the Spirit of the Rules, Builder Conduct, and Design Rules sections.

A Reset and Launching Point for the Future

NHRL has always embraced creativity and innovation. In our early days, we had a very permissive and minimalist rule-set. The rules were also fairly fluid, and were often changed event to event to respond to new and unforeseen designs, strategies, and dynamics. We fully embraced and encouraged the efforts of competitors to find the limitations of our rule-set, in the hopes that it would help us quickly iterate and improve.

As NHRL has grown, it has become more difficult to maintain a flexible and minimalist rule-set while also staying fair to competitors. Our rule-set has grown in size and complexity, and we made efforts to be more consistent with the application of the rules, while also being as permissive as possible. This resulted in some incredible innovations in NHRL, but has also had unexpected side effects that culminated in NHRL’s rules and rules enforcement being complex, confusing, and sometimes counter to the goals of the league.

For 2025, we’ve worked to address these issues, without making changes so drastic that they unnecessarily disadvantage competitors who have designed and built to our 2024 rule-set. There are more dramatic changes being considered for future years, but the primary goal of the 2025 rule-set is to create a simpler, more balanced, and more stable basis that can be improved upon in future years.

Changes to the Spirit of the Rules

We believe it is important to highlight the change in the Spirit of the Rules. In the past, we intentionally allowed vague rules to exist and the builder community responded creatively and competitively, and we allowed the resulting robots to compete for subsequent events.

We are changing our approach moving forward. In writing the 2025 rule-set, we have sought out and removed many rules that were ambiguous or open ended. In areas of the rules that require a level of open-endedness, we have added wording that builders gain approval from NHRL for their designs and strategies before competing. For those topics where design approval is needed, NHRL will use its discretion, balancing competitive integrity, innovation, entertainment, and builder fun.

We continue to encourage builders to break new ground with their designs and strategies, but we want this to be done in their workshops, in the pits, and in the arena, rather than in the wording of the rules. If the intention of a rule is unclear, a competitor should ask for clarification before they commit to a build or strategy. We will be less permissive in allowing designs and strategies that are not in the spirit of the rules, and will clarify and expand the rules in response to designs that we believe detract from the competitive integrity or fun of the event.

At times, NHRL may decide to allow certain designs or strategies on a trial basis. This will be done with input from Tournament Stewards and staff, and we will likely ask for input from one or more builders from the community. Inclusion of a design at one event does not mean that the design will be approved for future events.

Looking Forward

While not included in the current rules, we have several concepts that we know will be considered in future rules changes. A few of these include:

• Reduction, elimination, or other changes to the shuffler weight bonus
• Rules or policies that increase the diversity of robot weapon type
• Rules that further encourage the development of True Walker robots
• Rules that encourage AI and other “smart” robot systems

Rules Changes and Cadence

In the near future, NHRL plans to release a guide outlining the types of rule changes and timing thereof. We understand that changes can have major consequences for builders, so we endeavor to take builders into account when modifying the rules, and to give them as much advance notice of major changes as possible. Changes to the rules are roughly categorized into the following categories with the following change frequency.

• Safety Changes: Safety concerns supersede all other considerations. NHRL reserves the right to modify or create rules at any time when necessary to protect competitors, spectators, and staff.
• Clarifications and Extensions: Language in the rules may be changed in light of issues or questions that arise event to event. These changes generally do not contradict existing rules, simply clarify their intent and application.
• Minor Changes: NHRL will conduct a mid-season review of the rules and tournament processes, with input from builders, Tournament Stewards, and event staff. Minor changes should either affect a small number of competitors, affect many competitors in minor ways, or both.
• Major Changes: Major changes will primarily occur between seasons, preferably with 3 to 6 months between the announcement and the enforcement. Major changes will occur only with a detailed examination of the existing rules and ramifications of the change, and will involve input from builders, Tournament Stewards, and NHRL staff.

Additional Sections and Context

In addition to the published sections of the 2025 Rules, changes are being made to the tournament processes, judging criteria, and other sections. Some changes to the design rules will relate to these changes in other sections, although we do not anticipate that these changes will greatly affect the designs of robots for the 2025 season - just the details of how they compete.

One major exception to this will be our rules regarding the definition of a robot. Robot events often have a “Ship of Theseus” issue, where it is difficult to determine how much a robot can change between matches and events while still being considered the same robot.

For the NHRL Open 2025 Season, we will be shifting to a more builder-centric definition of a robot. Generally speaking, a robot must be captained by the same person or persons to be considered the same robot, unless given specific permission from NHRL to switch captains. We will also be releasing specifics on how much a robot can change between events while still being considered the same robot. Because we want to enable builders to advance quickly in the sport, this will be a *very* permissive system. Generally speaking, a robot should maintain its weapon type, its drive system, the number of weapons and wheels/tracks/legs, and any weight bonuses. Otherwise, a builder is free to drastically redesign their robot. We will ask that builders maintain visual cues and styling between revisions when possible, but this will not be a requirement.