Edition: 2026/Official

Format: Remote Controlled (RC) HUMANOID SUMO

1. ROBOT TECHNICAL SPECIFICATIONS

1.1. Physical Limits: * Mass: Max 3000.0g.

• Dimensions: Max 200mm x 200mm (Static footprint). Height Max 500mm.

• Structure: Must have 2 legs, 2 arms, and 1 head. No wheels or auxiliary supports.
  1.2. The Gait Requirement: * Locomotion must be bipedal. During a walking cycle, the swinging foot must completely clear the surface.

• The Paper Test: The robot must take at least 3 consecutive steps over an 80g/m² sheet of paper without snagging, dragging, or crumpling it.
  1.3. Connectivity & Power:

• Allowed: 2.4GHz RC, Bluetooth, Console Gamepads (PS/Xbox).

• Failsafe: Must cease all movement if signal is lost. Failsafe must stop motion within 1 second.

• Liability: Connectivity is the Pilot's responsibility. If a signal drops (Bluetooth lag/interference), the match continues. The opponent may score on a "frozen" robot.

• Battery: Must be safely secured. A "brown-out" or power loss is treated as a Slipdown.

2. PILOT CONDUCT & POSITIONING

2.1. The Pilot Box: * Pilots must stand within a marked 1m x 1m box, located 1.5 meters from the ring edge.

• Stepping out of the box during a round = 1-point penalty.
  2.2. Line of Sight: * Pilots must remain at their assigned station. Walking around the ring or obstructing the opponent’s view/cameras is strictly prohibited and results in immediate Disqualification (DQ).
  2.3. Touching the Robot: * Once the referee calls "Hajime," pilots cannot touch the robot until "Matte" or "Soremade" is called.

3. SCORING & MATCH FLOW

3.1. Match Format: Best of 3 rounds. Each round is 1:30 minutes.

3.2. Yuhkoh (Points): * Ringout (3 Pts): Touches the floor outside the ring.

• Knockdown (2 Pts): Falls due to contact and stays down for 3 seconds.

• Slipdown (1 Pt): Falls due to own error/technical failure.

If a fall occurs immediately after opponent contact, it is always Knockdown.

3.3. The Reset Limit: * A maximum of two (2) technical resets per round (for stalling or double-falls) are permitted.

• If a third reset is required, the referee ends the round and awards a Judge’s Decision (Yusei-Gachi).

4. THE ENGAGEMENT & CENTER RULES

To prevent stalling, the referee enforces "Center Dominance."

Center is measured from the geometric center of the dohyo to the center of mass projection of the robot.

4.1. An attack is defined as forward movement that reduces the distance to the opponent.

4.2. Edge-Hugging: Remaining in the outer 10cm of the ring for >5 seconds without attacking. The outer 10 cm is measured inward from the inner edge of the white boundary line.

4.3. Stalling: Avoiding contact for >10 seconds.

4.4. Grabbing, locking, or lifting the opponent in a way that prevents separation is prohibited.

4.5. Tie-Breaker Priority (for Judge’s Decisions):

1. Movement Priority: The robot actively walking toward the opponent.

2. Center Dominance: The robot controlling the center of the ring. 

3. Standing Priority: The robot that stands up fastest after a fall.

4. If still equal → Replay the round

ANNEX A: REFEREE VERBAL SCRIPT

Referees must use these specific commands to maintain authority and clarity.

ANNEX B: PRE-MATCH TECHNICAL INSPECTION (TI)

Must be completed for every robot.

[ ] Weight: ≤ 3000g (Actual: _______)

[ ] Size: 200mm x 200mm Square Test [PASS/FAIL]

[ ] Gait: Paper Test [PASS/FAIL]

[ ] Signal: 30-second connectivity stress test [PASS/FAIL]

[ ] Failsafe: Power-off controller test (Robot must stop) [PASS/FAIL]

[ ] Stand-up: Robot can stand up from belly and back [REQUIRED]

ANNEX C: SUMMARY OF PENALTIES (REF TABLE)