Exercise Therapy Control Using Response Time Constant Lag
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing exercise therapy devices, such as ergometers and treadmills, fail to adequately account for individual differences in response time constants of exercisers' heart rates, leading to excessive exercise loads, particularly for those with cardiac disease, as they do not consider the varying response time constants when adjusting exercise loads based on heart rate or pulse rate.
Innovation Solution
A control apparatus and method that calculates a first-order lag waveform of the target heart rate value based on the exerciser's response time constant, allowing for a corrected target value to be set, which helps in generating a command value for the exercise load to ensure it does not exceed safe limits, thereby preventing excessive load application.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the exercise load is controlled based on the difference between the target heart rate value and the measured heart rate value without considering the response time constant, then the control system is simple and responsive, but the exercise load becomes excessively large for exercisers with large response time constants (e.g., cardiac disease patients)
Solution Approach 1:
The control apparatus performs preliminary action by calculating a corrected target heart rate value that anticipates the delayed response of exercisers with large response time constants. Before applying the full target heart rate value, the system pre-adjusts it based on the response time constant, thereby preventing excessive exercise load from being applied in the first place rather than reacting after the problem occurs.
Solution Approach 2:
The system changes the parameter of the target heart rate value by applying a correction based on the response time constant. The corrected target heart rate value is calculated as a function of the original target value and the response time constant, thereby adapting the control parameter to match the exerciser's physiological characteristics and avoid excessive load.
2Reliability
If the response time constant is taken into consideration to calculate a corrected target heart rate value, then the exercise load control becomes more accurate and safe, but the control system complexity increases
Solution Approach 1:
The control apparatus implements feedback by continuously monitoring the measured heart rate value and comparing it with the corrected target heart rate value. The system uses the response time constant as a feedback parameter to dynamically adjust the exercise load control, thereby improving reliability while maintaining a manageable level of complexity through systematic feedback processing.
Solution Approach 2:
The response time constant serves as an intermediary parameter that mediates between the target heart rate value and the actual exercise load control. By introducing this intermediate correction factor, the system achieves more accurate and safe load control without requiring fundamentally complex control architecture, as the intermediary simplifies the relationship between target and actual values.
3Ease of operation
If a fixed target heart rate value is used for all exercisers, then the control system is simple to operate, but it cannot accommodate individual differences in response time constants among exercisers
Solution Approach 1:
The system transitions from a static fixed target heart rate value to a dynamic corrected target heart rate value that adapts to individual exercisers based on their response time constants. The corrected target value is dynamically calculated considering each exerciser's physiological characteristics, thereby achieving individualization while maintaining ease of operation through automated calculation.
Solution Approach 2:
The system changes the target heart rate parameter from a fixed universal value to a variable corrected value that depends on the individual exerciser's response time constant. This parameter transformation enables the system to accommodate individual differences while keeping the user interface simple, as the parameter adjustment occurs automatically based on measured physiological data.
Data Source
AI summary
Provided are a control apparatus and method for an exercise therapy device, including the following steps: calculating a first-order lag waveform of a waveform of the target value of the exercise physiological response as a corrected target value of the exercise physiological response using a response time constant; calculating a difference between the corrected target value of the exercise physiological response and the measured value of the exercise physiological response as an exercise physiological response deviation after correction; generating a command value for the exercise load based on the exercise physiological response deviation after correction, so that the exercise physiological response of the exerciser approaches the corrected target value of the exercise physiological response, to thereby control the exercise load to be applied to the exerciser.