Movement Phase Tracker
Understanding State Machines
We plan to use a state machine to count the number of reps an athlete has completed in a set. A state machine is like a smart checklist or flowchart that knows exactly which phase of the wall ball exercise is happening - whether the athlete is squatting down, throwing the ball, or catching it. The system can only be in one state at a time and moves between states based on specific rules, ensuring every repetition follows the correct sequence for valid counting.
This state machine component will serve as the intelligent decision-making core of the HYROX judging system, analyzing movement patterns to identify valid wall ball cycles and enforce competition-standard form validation. The system will process movement data over time to detect when a rep begins, validate proper squat depth, confirm ball contact with targets, and ensure completion criteria while maintaining the precision required for competitive judging applications.
State Machine Architecture
The state machine provides structured temporal analysis of wall ball movements, systematically tracking athletes through each phase of the exercise cycle to ensure comprehensive validation of competition standards. This rule-based approach enables consistent judging decisions while maintaining transparency in automated validation logic.
Core State Definitions
The proposed system would implement a comprehensive finite state machine with eight distinct states that capture the complete lifecycle of a wall ball repetition:
Finite state machine showing valid and invalid transition paths for wall ball repetition counting
Ready State represents the starting position where the athlete stands upright with the ball held at chest level. The computer vision system will verify full hip and knee extension, confirming the athlete is prepared to begin the next repetition. Human judges will look for a brief pause in the standing position to ensure no bouncing between reps occurs.
Descent State begins when the athlete starts the controlled downward movement into the squat position. The system will track the rate of hip and knee bending, ensuring smooth controlled movement rather than dropping or bouncing. Joint angles will be continuously monitored as the athlete descends toward the required depth position.
Bottom State occurs at the critical validation point when the athlete reaches maximum squat depth. The system will precisely measure whether the hip crease has descended below the knee level using three-dimensional spatial analysis. This measurement will account for individual body proportions while maintaining strict adherence to competition standards, with human judges visually confirming the hip-knee relationship from their positioned viewpoint.
Ascent State tracks the athlete driving upward from the squat position toward standing. The system will monitor the acceleration pattern and joint extension sequence to ensure proper form. The ascent must be continuous without pausing or segmented movement that could indicate fatigue or improper technique.
Throw State activates when the athlete reaches the standing position and releases the ball toward the target. The system will track ball trajectory, release point, and projected impact location. Release timing relative to full standing position will be validated to ensure proper exercise sequencing.
Target Hit State confirms when the ball makes contact with the designated target zone. The system will verify impact occurred at the correct height (10 feet for men, 9 feet for women) and within the acceptable target area. Ball impact patterns will confirm solid contact versus glancing blows.
Catch State validates that the athlete receives the descending ball with control. The system will verify the ball was caught cleanly without dropping or bobbling, with both hands maintaining control. Proper catching position at chest level will be confirmed before allowing transition to the next repetition.
Complete State finalizes the valid repetition counting and recording. The system will log all validation metrics, update the rep counter, and prepare to track the next repetition cycle. Any validation failures during the sequence will instead trigger a transition to the No-Rep state with specific feedback about the violation.
Wall Ball Validation Requirements
Based on HYROX competition standards, the state machine would enforce specific validation criteria for each wall ball repetition:
Target Height Requirements will specify precise elevation standards based on athlete category and gender. Men must hit targets at 10 feet (3.048m) while women target 9 feet (2.743m), with ball contact required at the center of the target zone for valid repetition counting. Professional divisions will maintain the same height requirements as standard categories to ensure consistent competition standards.
Ball Weight Standards will ensure consistent resistance across all competition categories. Men will use 9kg (20lbs) wall balls while women will use 6kg (14lbs) implements, with professional divisions maintaining identical weight requirements to standard categories. These specifications will align with official HYROX competition regulations and ensure fair competition standards across all athlete categories.
Movement Standards will define the complete exercise execution requirements for valid repetitions. Squats must reach parallel or below with hip crease positioned below knee level, while athletes must catch the ball before initiating the next repetition. Full standing position must be achieved between reps with no dropping of the ball, requiring controlled descent followed by explosive upward movement patterns.
Form Validation will encompass comprehensive technique requirements beyond simple depth measurement. Hip crease must pass below knee level during the squat phase, while full hip and knee extension is required at the standing position. Ball contact confirmation with designated target height must occur, followed by proper catching technique with ball control before beginning the next repetition, with no bouncing permitted at the bottom of the squat position.
Each state transition would require specific biomechanical criteria to be satisfied, ensuring that only properly executed repetitions advance through the complete state sequence. Advanced temporal analysis would prevent premature state transitions that could result from detection noise or brief occlusion events.
Validation Rule Implementation
The proposed state machine would enforce HYROX's official competition standards through precise geometric analysis of 3D pose data and ball tracking. The critical squat depth requirement—hip crease positioned below knee level—would be validated through sophisticated spatial analysis that accounts for individual athlete anthropometry and measurement uncertainty.
Additional Validation Rules encompass comprehensive movement quality requirements beyond basic positional criteria. Controlled movement tempo requirements prevent bouncing or partial repetitions that could compromise exercise integrity.
Wall Ball Contact and release timing validation ensure proper exercise execution with confirmed target impact.
Target Height Validation occurs for each throw to verify compliance with competition standards, while ball catching requirements must be satisfied before initiating the next repetition.
Form Consistency Checks identify and reject compensatory movement patterns that may indicate improper technique or attempts to circumvent proper exercise execution.
Squat Depth Validation Logic
Geometric Analysis Framework
The proposed system would perform precise 3D geometric calculations to determine hip-to-knee spatial relationships using advanced algorithms that account for joint center estimation uncertainty and measurement confidence. Hip crease positioning would be calculated through sophisticated anatomical modeling that considers individual athlete body proportions and movement patterns.
Multi-frame validation would prevent false positives from brief measurement artifacts or temporary occlusion events. The system would require consistent depth achievement across multiple consecutive frames (typically 150-300ms) to confirm valid squat depth, ensuring robust validation even under challenging detection conditions.
Anthropometric Adaptation
Individual athlete characteristics would significantly impact squat biomechanics and optimal depth achievement strategies. The proposed system would implement adaptive validation thresholds that account for limb length ratios, joint mobility variations, and anthropometric differences while maintaining consistent competition standards.
Gender-specific biomechanical models would provide tailored validation criteria that reflect documented differences in squat movement patterns between male and female athletes. These adaptations would ensure fair and accurate judging across all athlete categories while preserving the integrity of competition standards.
Temporal Analysis and Movement Quality
Movement Pattern Recognition
Sophisticated temporal analysis algorithms would identify characteristic movement signatures associated with proper wall ball execution. The system would analyze movement velocity profiles, joint angle progressions, ball trajectory patterns, and coordination patterns to distinguish between valid repetitions and compensatory movements that may appear geometrically correct but violate proper form requirements.
Advanced pattern matching would detect common form violations including knee valgus collapse, forward lean compensation, inadequate hip hinge patterns, improper ball release timing, and insufficient target contact. These biomechanical assessments would provide comprehensive form validation beyond simple depth measurement, ensuring complete adherence to exercise standards.
Rhythm and Tempo Validation
Proper wall ball execution would require controlled movement tempo with distinct phases for descent, pause at depth, explosive ascent, ball release, target contact, and controlled catch. The state machine would analyze movement timing to identify and reject rapid bouncing motions, incomplete range-of-motion attempts, dropped balls, or missed target contacts that may appear to meet some requirements without proper exercise execution.
Temporal consistency requirements would prevent gaming of the validation system through artificially rapid or segmented movements. The system would enforce minimum duration requirements for each movement phase while accommodating natural variations in individual athlete movement preferences and capabilities.
Competition Rule Enforcement
HYROX Standard Compliance
The proposed state machine would implement complete adherence to official HYROX competition standards through comprehensive rule validation logic. Beyond squat depth requirements, the system would enforce ball contact rules, target height validation, throwing accuracy requirements, catch control standards, and full standing position requirements that comprise complete wall ball exercise validation.
Advanced rule interpretation would handle edge cases and boundary conditions that may arise during competition. The system would provide consistent rule application across all athletes while maintaining the flexibility to accommodate individual movement variations that remain within competition standards.
Adaptive Division Considerations
Special accommodation algorithms would address the unique requirements of adaptive division athletes who may have movement limitations that affect standard exercise execution. These algorithms would maintain competitive integrity while providing appropriate modifications for athletes with physical adaptations or limitations.
Customizable validation parameters would allow for individual athlete accommodations while preserving automated judging capabilities. The system would maintain detailed logs of any modified validation criteria to ensure transparency and consistency in adaptive division competition management.
Performance and Reliability
Real-Time Decision Making
The state machine operates with deterministic timing characteristics, providing consistent decision-making performance regardless of system load or environmental conditions. Sub-millisecond state transition decisions ensure that validation logic never becomes a bottleneck in the overall system latency budget.
Advanced buffering and prediction algorithms provide robust operation even during temporary data quality degradation. The system maintains state consistency through brief occlusion events or detection uncertainties, ensuring continuous operation throughout complete exercise sequences.
Error Handling and Recovery
Comprehensive error handling prevents state machine corruption during challenging conditions such as severe occlusion, detection failures, or temporary hardware issues. Robust recovery mechanisms restore normal operation without losing tracking continuity or requiring system restart.
Advanced validation prevents impossible state transitions that could result from sensor noise or detection errors. The system maintains logical consistency through comprehensive state validation and automatic error correction that preserves operational integrity.
Integration and Data Flow
Pipeline Component Coordination
Seamless integration with upstream pose estimation and tracking components ensures optimal data utilization for state machine decision-making. The system processes rich metadata including pose confidence scores, tracking stability metrics, and measurement uncertainty to make informed validation decisions.
Tight coordination with downstream feedback systems ensures immediate communication of rep validation decisions to athletes and judges. Real-time status updates provide continuous visibility into exercise progression and validation state for optimal user experience.
Quality Assurance and Monitoring
Comprehensive performance monitoring tracks state machine accuracy, decision consistency, and timing performance across all active stations. Advanced analytics identify patterns that may indicate validation logic optimization opportunities or environmental factors affecting decision quality.
Detailed audit logging captures all validation decisions with supporting biomechanical data, providing complete transparency for dispute resolution and system performance analysis. These audit trails support evidence-based system improvements and competitive integrity maintenance.