A student reaction force and lower limb strength interesting exercise test method based on dynamic difficulty adjustment

Abstract

This invention discloses a fun exercise test method for student reaction time and lower limb strength based on dynamic difficulty adjustment. The method uses a camera to acquire an initial posture image of the student, presenting a "wooden hammer" pattern on the screen as a stimulus signal. The student is required to complete a squatting motion within a preset time and hold the position until the pattern disappears. The system extracts the coordinates of key skeletal points of the student in real time and calculates the squatting motion score frame by frame based on these coordinates. This score is composed of the product of squatting posture score, symmetry score, balance score, height score, and displacement score. Student performance is evaluated by calculating the completion degree score, the action completion time score, and the action completion score. The system sets a fixed interval between the first few appearances of the wooden hammer, and then calculates an adjustment score for action quality and student speed based on historical data, achieving dynamic adjustment of the test difficulty. This invention can objectively assess students' reaction time and lower limb strength, improving the fun and adaptability of the test.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of sports testing methods, and in particular to a student reaction force and lower limb strength interesting sports testing method based on dynamic difficulty adjustment. BACKGROUND

[0002] With the improvement of children's health awareness and the development of physical education, student physical fitness testing has become an important means to assess the physical fitness of adolescents. Traditional physical fitness testing methods mainly assess students' reaction ability and lower limb strength through standardized motion testing, but face many challenges in practical application.

[0003] Existing physical fitness testing technologies have developed to some extent. Chinese patent CN116650922A discloses a comprehensive testing method for adolescent physical fitness based on deep learning, which realizes the testing of multiple physical fitness indicators such as strength, flexibility, and balance through human posture estimation and image recognition technology. Chinese patent CN109513198A discloses a multifunctional muscle strength assessment and exercise feedback system that can collect and feedback data for muscle strength training. Chinese patent CN114011026A provides a non-contact physical fitness testing system that uses human posture recognition technology to accurately count sit-ups, push-ups, and other movements. In addition, Chinese patent CN114367086A discloses a lower limb rehabilitation training game system that uses a game-like form to enhance the interest of training.

[0004] However, the existing technology still has significant deficiencies: first, the testing form is monotonous and boring, most systems use fixed position buttons or monotonous sound and light signals for reaction force testing, and lower limb strength assessment relies on repetitive mechanical movements, lacking game design and interesting elements, resulting in low participation enthusiasm and difficulty in concentrating attention of children; second, the difficulty setting is fixed, existing methods generally use uniform standards for testing, which cannot adapt to the ability differences of different individuals, and children with strong ability feel that the test is too simple and lacks challenge, while children with weak ability may experience frustration; third, there is a lack of intelligent dynamic adjustment mechanism, which cannot adaptively adjust the task difficulty according to the real-time performance of children, affecting the accuracy of test results and possibly causing safety hazards; finally, the evaluation dimension is relatively single, existing technologies often separate reaction force and strength testing, which cannot effectively reflect the comprehensive explosive force performance of children under rapid reaction conditions, and is difficult to fully assess their sports ability. SUMMARY

[0005] To address the technical problems of existing children's physical fitness testing methods, such as monotonous testing formats, rigid difficulty settings, lack of intelligent adjustment mechanisms, and single assessment dimensions, and to achieve the technical effects of improving children's participation, intelligently adapting to individual differences, and comprehensively assessing reaction ability and lower limb strength, this paper proposes a fun sports test method for students' reaction ability and lower limb strength based on dynamic difficulty adjustment.

[0006] The technical problem this invention aims to solve is that existing methods for testing children's physical fitness have the following drawbacks: the testing methods are monotonous and boring; reaction time tests often use fixed-position buttons or monotonous sound and light signals; lower limb strength assessment relies on repetitive mechanical movements, lacking gamification and storylines, resulting in low participation and difficulty in concentrating among children; the difficulty settings are rigid, and the use of uniform standards cannot adapt to different individual differences, causing high-ability children to feel bored and low-ability children to experience frustration; there is a lack of intelligent adjustment mechanisms, which cannot dynamically adjust the difficulty of tasks based on children's real-time performance, affecting both test accuracy and safety hazards; and the assessment dimensions are singular, separating reaction time and strength tests, failing to reflect the comprehensive explosive power under rapid reaction.

[0007] The technical solution adopted by this invention to solve its technical problem is: a fun exercise test method for student reaction ability and lower limb strength based on dynamic difficulty adjustment, comprising the following steps: S1. The student stands in the designated test area, and the system acquires the student's initial posture image through the camera. S21. The system displays a "wooden hammer" pattern on the screen as a stimulus signal. Students need to complete the squatting action within a preset time threshold t1 and maintain the squatting posture until the wooden hammer pattern disappears (the number of frames of dwell time t2). S22. Acquire student images in real time via camera and extract key skeletal point coordinates: neck coordinates (nx) ij ny ij ), left hip coordinates (ulx) ij uly ij ), right hip coordinates (urx) ij ,ury ij Left knee coordinates (klx) ij ,kly ij ), right knee coordinates (krx) ij ,kry ij ), left foot coordinates (flx) ij fly ij ), right foot coordinate (frx) ij fry ij ), where the subscript ij represents the j-th frame after the i-th appearance of the "wooden hammer" pattern; S3. Based on the extracted skeletal point coordinates, calculate the squatting motion score (gd) frame by frame. ij The gdij The score for the squatting posture is gd1 ij Squatting symmetry score gd2 ij Balanced score gd3 ij High score gd4 ij And displacement score gd5 ij The product; S4. After a fixed time frame t3, calculate the completion score gf. ij When the average value of gd within the most recent t3 frames is greater than the second judgment threshold ts2, it is determined that the student has performed a standard squatting action; the action completion time score gt is calculated. i Record the time taken to complete each squat; calculate the score for completing the squat. i When the average value of gd during the time period from t1 to t2 is greater than the third judgment threshold ts3, it is determined that the student has completed the squatting action according to the standard and continues until the pattern disappears. S5. Score based on completion of the action. i Calculate the score for each individual attempt, and sum the scores of all attempts to obtain the final sports score gs; S61. Set the interval between the first n2 (n2>6) appearances of the wooden hammer to a fixed time frame t4. S62. When the number of attempts i > n2, calculate the motion quality adjustment score gz1 based on the historical data of the previous n2 attempts. i And student speed adjustment score gw i ; S63, based on gz1 i and gw i Calculate the time frame difference td between the i-th and (i-1)-th appearances of the wooden hammer. i This allows for dynamic adjustment of the test difficulty; among which gz i Based on the quality criterion score gz1 i To assess the quality of students' squatting movements, gw i Based on the speed criterion, score gw1 i And fluctuation criterion score gw2 i Assess the speed and stability of students' squatting movements.

[0008] Preferably, the squatting posture score gd1 ij The calculation formula is: .

[0009] Preferably, the squatting symmetry score gd2 ij The calculation formula is: .

[0010] Preferably, the balance score gd3 ij The calculation formula is: .

[0011] Preferably, the height score gd4 ij The calculation formula is: .

[0012] Preferably, the displacement score gd5 ij The calculation formula is: .

[0013] Where ts1 is the set first judgment threshold.

[0014] Preferably, the calculation completion score gf ij The calculation formula is: ; Among them, gd im ts2 is the score for the squatting action in the m-th frame after the i-th appearance of the "wooden hammer" pattern; ts2 is the set second judgment threshold. The action completion time score gt i The calculation formula is: ; Where t2 is the number of frames the hammer pattern stays on the screen; The action was completed and scored ge i The calculation formula is: ; Where ts3 is the set third judgment threshold.

[0015] Preferably, the formula for calculating the final motion score gs is: ; Where n1 is the number of times the "wooden hammer" appears; g c This is the base score for completing a single action.

[0016] Preferably, the motion quality adjustment score gz i The calculation formula is: ; Where ts4 is the set fourth judgment threshold, ts5 is the set fifth judgment threshold, and gz1 i The quality criterion score; the action quality adjustment score gz1 i The calculation formula is: ; Among them, ge hLet n be the score for completing the action of the wooden hammer pattern in the hth time, and n2 be the historical count and n2>6; The student speed adjustment score gw i The calculation formula is: ; Where ts6 is the set sixth judgment threshold, ts7 is the set seventh judgment threshold, and gw1 i The score is determined by speed, gw2 i Scoring based on fluctuation data; The gw1 i The formula for calculating the score based on speed is: ; Among them, gt h The score is the time taken to complete the h-th hammer pattern action. The gw2 i The formula for calculating the criterion score for fluctuation data is as follows: .

[0017] Preferably, the time frame difference td between the i-th and (i-1)-th occurrences of the wooden hammer is... i The calculation formula is: td i =int(gz) i gw i t4); Here, int() is the floor function, and t4 is the initial fixed interval time frame number.

[0018] The beneficial effects of this invention are as follows: By designing a fun "Monster is Coming" game scenario, the traditionally tedious physical fitness test is transformed into a lively and engaging interactive game, effectively improving children's enthusiasm and concentration during testing, and solving the problem of the traditional test format being dull and boring; an intelligent dynamic difficulty adjustment mechanism is established, which can adaptively adjust the task difficulty according to students' real-time performance, increasing rest time and reducing difficulty for students with declining abilities, while reducing intervals and increasing difficulty for students with outstanding abilities, avoiding the shortcomings of uniform standards that cannot adapt to individual differences; a comprehensive assessment of reaction speed and lower limb strength is achieved, using a multi-dimensional scoring system including indicators such as squatting posture, symmetry, balance, height, and displacement to comprehensively reflect students' comprehensive explosive power under rapid reaction, overcoming the limitations of traditional separate tests; the accuracy and safety of the test are improved, by intelligently adjusting the test difficulty through real-time monitoring of students' movement quality and completion speed, ensuring that the test process is both challenging and within the students' capabilities, effectively avoiding safety hazards. Detailed Implementation

[0019] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to embodiments. The content mentioned in the embodiments is not intended to limit the present invention.

[0020] Example 1 A fun sports test method for assessing student reaction time and lower limb strength based on dynamic difficulty adjustment is an intelligent testing method that uses a fun sports game format called "Monster is Coming" to comprehensively evaluate students' reaction ability and lower limb strength through computer vision technology and a dynamic difficulty adjustment mechanism. This method captures students' movement postures in real time using a camera, and combines a multi-dimensional scoring system and an adaptive difficulty adjustment algorithm to achieve accurate assessment of students' physical fitness levels.

[0021] S1. The student stands in the designated testing area, and the system acquires an initial posture image of the student via a camera. Before the test begins, the student needs to stand in the preset testing area, maintaining a natural standing posture. The system uses a high-definition camera to capture the student's initial posture image, establishing a benchmark reference for subsequent motion recognition and evaluation. The camera is set at an appropriate angle and distance to ensure that it can fully capture the student's full range of motion, especially the positional information of key skeletal points.

[0022] S21. The system displays a "wooden hammer" pattern on the screen as a stimulus signal. Students must complete a squatting motion within a preset time threshold t1 and maintain the squatting posture until the hammer pattern disappears. The hammer pattern remains on the screen for t2 frames. When the "wooden hammer" pattern appears on the screen, it serves as a visual stimulus signal, prompting students to react immediately. Students must quickly transition from standing to squatting within the preset time threshold t1 and maintain a standard squatting posture until the hammer pattern disappears from the screen. The hammer pattern remains on the screen for t2 frames, during which time students must continuously maintain the squatting motion, testing their lower limb strength and endurance.

[0023] S22. Acquire student images in real time via camera and extract key skeletal point coordinates: neck coordinates (nx) ij ny ij ), left hip coordinates (ulx) ij uly ij ), right hip coordinates (urx) ij ,ury ij Left knee coordinates (klx) ij ,kly ij ), right knee coordinates (krx) ij ,kry ij ), left foot coordinates (flx) ij fly ij ), right foot coordinate (frx) ij fry ijThe system employs an advanced human posture recognition algorithm to analyze the image sequence captured by the camera in real time and accurately extract the coordinate information of key skeletal points on the student's body. These skeletal points include seven key locations: the neck, left and right hips, left and right knees, and left and right feet. By analyzing the coordinate changes of these points, the system can accurately determine the student's movement state and posture quality. The design of the subscript ij facilitates tracking the changes in skeletal point positions in each time frame after the appearance of the wooden hammer.

[0024] S3. Based on the extracted skeletal point coordinates, calculate the squatting motion score (gd) frame by frame. ij The gd ij The score for the squatting posture is gd1 ij Squatting symmetry score gd2 ij Balanced score gd3 ij High score gd4 ij And displacement score gd5 ij The system assesses the standard of a student's squatting posture by comprehensively analyzing multiple dimensions of movement quality indicators. Squatting posture score gd1 ij The standard squatting posture is determined by judging the relative positions of the hips, knees, and feet. The calculation formula is as follows: .

[0025] This ensures that the hips are higher than the knees, and the knees are higher than the feet, forming a standard squatting position.

[0026] Squat symmetry score gd2 ij The symmetry of the movement is assessed using the following formula: .

[0027] This scoring standard ensures that the student's knees are correctly positioned inside the corresponding hips on both sides, maintaining the symmetry and stability of the movement.

[0028] Balanced score gd3 ij The formula for assessing a student's balance during a squat is as follows: .

[0029] This standard requires students to keep their necks near the center line of their body, avoiding excessive forward or backward tilting, and demonstrating good balance control.

[0030] High score gd4 ij To assess whether the squat depth meets the standard, the calculation formula is: .

[0031] This requires students to keep their necks below their knees to ensure that the squatting motion reaches a sufficient depth and fully exercises the lower limb muscle groups.

[0032] Displacement score gd5 ij The formula for assessing a student's positional stability during a squat is: .

[0033] ts1 is the set first judgment threshold. This score ensures that the student's foot position remains relatively stable during the squatting process, avoiding unnecessary displacement.

[0034] S4. After a fixed time frame t3, calculate the completion score gf. ij When the average value of gd within the most recent t3 frames is greater than the second judgment threshold ts2, it is determined that the student has performed a standard squatting action; the action completion time score gt is calculated. i Record the time taken to complete each squat; calculate the score for completing the squat. i When the average value of gd during the time interval t1 to t2 is greater than the third judgment threshold ts3, it is determined that the student has completed the squatting action according to the standard and continues until the pattern disappears.

[0035] Completion score gf ij The calculation formula is: .

[0036] Among them, gd im ts2 is the score for the squatting action in the m-th frame after the i-th appearance of the "wooden hammer" pattern; ts2 is the set second judgment threshold. This scoring mechanism determines whether the student has stably completed the standard squatting action by analyzing the average level of action quality within consecutive t3 frames.

[0037] Action completion time score gt i The calculation formula is: .

[0038] Where t2 represents the number of frames the hammer pattern remains on the screen. This calculation method can accurately record the time required for a student to complete a standard squatting motion from the start of their reaction, reflecting the student's reaction speed and motor execution ability.

[0039] Action completion score ge i The calculation formula is: .

[0040] ts3 is the set third judgment threshold. This scoring standard requires students to maintain high-quality squatting movements within a specified time window, ensuring the continuity and stability of the movement.

[0041] S5. Score based on completion of the action. i Calculate the score for each individual attempt, and sum the scores of all attempts to obtain the final sports score gs. The formula for calculating the final sports score gs is: , where n1 is the number of times the "wooden hammer" appears; g c This is the base score for each successful completion of a movement. The system calculates the student's overall performance by accumulating the scores for each successful completion of the movement. This score comprehensively reflects the student's responsiveness and lower limb strength level throughout the test.

[0042] S61. Set the interval between the first n2 appearances of the wooden hammer (n2>6) to a fixed time frame t4. In the initial stage of the test, the system uses a fixed time interval to present the wooden hammer pattern, providing students with an opportunity to adapt to the test rhythm and also collecting basic data for subsequent dynamic difficulty adjustments. n2 is set to a value greater than 6 to ensure sufficient sample data for reliable statistical analysis.

[0043] S62. When the number of attempts i > n2, calculate the motion quality adjustment score gz1 based on the historical data of the previous n2 attempts. i And student speed adjustment score gw i Once the initial fixed-interval phase is completed, the system begins dynamic analysis based on students' historical performance data. By calculating movement quality adjustment scores and speed adjustment scores, the system can comprehensively assess students' current state and trends in ability level.

[0044] Action quality adjustment score gz i Based on the quality criterion score gz1 i The calculation is performed using the following formula: .

[0045] Where ts4 is the set fourth judgment threshold, ts5 is the set fifth judgment threshold, and gz1 i Quality criterion score gz1 i The calculation formula is: , Among them ge h Let n be the score for completing the hammer pattern action in the h-th iteration, and n² be the historical count, where n² > 6. This calculation method assigns higher weight to recent performance, thus more accurately reflecting the student's current level of action quality.

[0046] Student speed adjustment score gw i The calculation formula is: .

[0047] Where ts6 is the set sixth judgment threshold, ts7 is the set seventh judgment threshold, and gw1 i The score is determined by speed, gw2 i The score is used to determine the criterion for fluctuating data.

[0048] Speed ​​judgment score gw1 i The calculation formula is: , Among them gt h The score is the completion time of the h-th hammer pattern movement. Fluctuation data criterion score gw2 i The calculation formula is: .

[0049] This comprehensive scoring system not only considers students' reaction speed but also analyzes the stability of that speed, and can identify trends in changes in students' physical fitness.

[0050] S63: Based on gz1 i and gw i Calculate the time frame difference td between the i-th and (i-1)-th appearances of the wooden hammer. i This allows for dynamic adjustment of the test difficulty. (Time frame difference td) i The calculation formula is: td i =int(gz) i gw i t4), where int() is the floor function and t4 is the initial fixed interval time frame. This dynamic adjustment mechanism can automatically adjust the test difficulty according to the student's real-time performance: when the student's action quality decreases or the reaction speed slows down, the system will appropriately increase the interval time of the hammer appearance, giving the student more rest and preparation time; when the student's performance is excellent and stable, the system will shorten the interval time, increase the test intensity, and realize personalized ability assessment and training.

[0051] This testing method, by integrating computer vision technology, multi-dimensional motion assessment, and intelligent difficulty adjustment mechanisms, can not only accurately assess students' reaction speed and lower limb strength, but also make personalized adjustments based on students' real-time performance, thereby improving the scientific nature and fun of the test and providing an innovative technical solution for students' physical fitness assessment and training.

[0052] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A fun exercise test method for students' reaction time and lower limb strength based on dynamic difficulty adjustment, characterized in that: Includes the following steps: S1. The student stands in the designated test area, and the system acquires the student's initial posture image through the camera. S21. The system displays a "wooden hammer" pattern on the screen as a stimulus signal. Students need to complete the squatting action within a preset time threshold t1 and maintain the squatting posture until the wooden hammer pattern disappears (the number of frames of dwell time t2). S22. Acquire student images in real time via camera and extract key skeletal point coordinates: neck coordinates (nx) ij ny ij ), left hip coordinates (ulx) ij uly ij ), right hip coordinates (urx) ij ,ury ij Left knee coordinates (klx) ij ,kly ij ), right knee coordinates (krx) ij ,kry ij ), left foot coordinates (flx) ij fly ij ), right foot coordinate (frx) ij fry ij ), where the subscript ij represents the j-th frame after the i-th appearance of the "wooden hammer" pattern; S3. Based on the extracted skeletal point coordinates, calculate the squatting motion score (gd) frame by frame. ij The gd ij The score for the squatting posture is gd1 ij Squatting symmetry score gd2 ij Balanced score gd3 ij High score gd4 ij And displacement score gd5 ij The product; S4. After a fixed time frame t3, calculate the completion score gf. ij When the average value of gd within the most recent t3 frames is greater than the second judgment threshold ts2, it is determined that the student has performed a standard squatting action; the action completion time score gt is calculated. i Record the time taken to complete each squatting movement; Calculate the score for completing the action (ge) i When the average value of gd during the time period from t1 to t2 is greater than the third judgment threshold ts3, it is determined that the student has completed the squatting action according to the standard and continues until the pattern disappears. S5. Score based on completion of the action. i Calculate the score for each individual attempt, and sum the scores of all attempts to obtain the final sports score gs; S61. Set the interval between the first n2 (n2>6) appearances of the wooden hammer to a fixed time frame t4. S62. When the number of attempts i > n2, calculate the motion quality adjustment score gz1 based on the historical data of the previous n2 attempts. i And student speed adjustment score gw i ; S63, based on gz1 i and gw i Calculate the time frame difference td between the i-th and (i-1)-th appearances of the wooden hammer. i This allows for dynamic adjustment of the test difficulty; among which gz i Based on the quality criterion score gz1 i To assess the quality of students' squatting movements, gw i Based on the speed criterion, score gw1 i And fluctuation criterion score gw2 i Assess the speed and stability of students' squatting movements.

2. The method for testing student reaction speed and lower limb strength using fun sports based on dynamic difficulty adjustment according to claim 1, characterized in that: The squatting posture score gd1 ij The calculation formula is: 。 3. The method for testing student reaction speed and lower limb strength using fun sports based on dynamic difficulty adjustment according to claim 1, characterized in that: The squatting symmetry score gd2 ij The calculation formula is: 。 4. The method for testing student reaction speed and lower limb strength using fun sports based on dynamic difficulty adjustment according to claim 1, characterized in that: The balance score gd3 ij The calculation formula is: 。 5. The method for testing student reaction speed and lower limb strength using fun sports activities based on dynamic difficulty adjustment according to claim 1, characterized in that: The height score gd4 ij The calculation formula is: 。 6. The method for testing student reaction speed and lower limb strength using fun sports based on dynamic difficulty adjustment according to claim 1, characterized in that: The displacement score gd5 ij The calculation formula is: ； Where ts1 is the set first judgment threshold.

7. The method for testing student reaction speed and lower limb strength using fun sports activities based on dynamic difficulty adjustment according to claim 1, characterized in that: The calculation completion score gf ij The calculation formula is: ； Among them, dg im ts2 is the score for the squatting action in the m-th frame after the i-th appearance of the "wooden hammer" pattern; ts2 is the set second judgment threshold. The action completion time score gt i The calculation formula is: ； Where t2 is the number of frames the hammer pattern stays on the screen; The action was completed and scored ge i The calculation formula is: ； Where ts3 is the set third judgment threshold.

8. The method for testing student reaction speed and lower limb strength using fun sports based on dynamic difficulty adjustment according to claim 1, characterized in that: The formula for calculating the final motion score gs is: ； Where n1 is the number of times "wooden hammer" appears; g c This is the base score for completing a single action.

9. The method for testing student reaction speed and lower limb strength using fun sports based on dynamic difficulty adjustment according to claim 1, characterized in that: The motion quality adjustment score gz i The calculation formula is: ； Where ts4 is the set fourth judgment threshold, ts5 is the set fifth judgment threshold, and gz1 i Assign a score to the quality criterion; The motion quality adjustment score gz1 i The calculation formula is: ； Among them, ge h Let n be the score for completing the action of the wooden hammer pattern in the hth time, and n2 be the historical count and n2>6; The student speed adjustment score gw i The calculation formula is: ； Where ts6 is the set sixth judgment threshold, ts7 is the set seventh judgment threshold, and gw1 i The score is determined by speed, gw2 i Scoring based on fluctuation data; The gw1 i The formula for calculating the score based on speed is: ； Among them, gt h The score is the time taken to complete the h-th hammer pattern action. The gw2 i The formula for calculating the criterion score for fluctuation data is as follows: 。 10. A fun exercise test method for student reaction speed and lower limb strength based on dynamic difficulty adjustment according to claim 9, characterized in that: The time frame difference td between the i-th and (i-1)-th appearances of the wooden hammer i The calculation formula is: td i =int(gz i gw i t4); Here, int() is the floor function, and t4 is the initial fixed interval time frame number.

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