Is a higher sampling frequency always better for a plantar pressure analysis system?

The sampling frequency of a plantar pressure analysis system is not necessarily better when higher; instead, the optimal range should be selected based on actual application needs. Excessively high sampling frequencies often lead to resource waste, while too low a frequency may result in loss of critical data.

Below is a detailed analysis:

1. Role of Sampling Frequency
Sampling frequency (measured in Hz, or data points collected per second) determines the system’s ability to capture dynamic pressure changes. Higher frequency enables richer recording of gait details and higher temporal resolution.

2. Recommended Sampling Frequencies for Different Scenarios

• Static Analysis (e.g., standing balance, center of gravity distribution)
  Recommended frequency: 50–100 Hz
  Reason: Pressure changes slowly when the body is stationary. A frequency of 100 Hz is sufficient to capture subtle shifts in center of gravity and stability. Higher frequencies offer no practical benefit.

• Routine Gait Analysis (e.g., walking assessment, rehabilitation training)
  Recommended frequency: 100–200 Hz
  Reason: A normal walking cycle lasts about 0.8–1.2 seconds, including key phases such as heel strike, mid-stance, and toe-off. A frequency of 200 Hz ensures each gait phase is adequately sampled, meeting clinical and rehabilitation evaluation requirements.

• High-Speed Motion Analysis (e.g., running, jumping, training for professional athletes)
  Recommended frequency: 300–500 Hz or higher
  Reason: Foot contact time during running is extremely short (often less than 200 milliseconds). High sampling frequency is required to accurately capture dynamic features such as impact peaks and pressure transition speed, enabling performance optimization and injury prevention.
  

• 
  

• 
  

3. Why “Higher is Better” Is a Misconception?

• Data Redundancy and Storage Pressure
  Doubling the sampling frequency doubles the data volume. For example, a 500 Hz system generates 2.5 times more data than a 200 Hz system, increasing storage costs and slowing down data processing.

• Significantly Increased Hardware Cost
  High-frequency data acquisition requires faster sensors, more powerful processing modules, and more stable transmission systems, leading to a substantial increase in equipment cost.

• Increased Software Processing Burden
  High-frequency data demands more powerful algorithms and longer processing times, potentially degrading user experience, especially in real-time feedback applications.

• Prev： What is the impact of sampling frequency on plantar pressure distribution heatmaps? Next：What are the differences between a 3D foot scanner and a plantar pressure distribution system?

  Back to list