Detect contact windows for one or more force plates

Identifies threshold-based contact windows from vertical GRF signals.

Usage

detectForcePlateContacts(vgrf, threshold = 20, sampling_rate = NULL)

Arguments

vgrf

Numeric vector or matrix of vertical GRF (rows = time, columns = plates/channels).

threshold

Contact threshold in force units.

sampling_rate

Optional sampling rate in Hz. If provided, durations are returned in seconds.

Value

A data.frame with one row per detected contact and columns: plate, stance, onset, offset, duration_samples, duration_s, and peak_force.

References

Winter DA (2009). "Biomechanics and Motor Control of Human Movement." 4th ed. John Wiley & Sons.

See also

analyzeForcePlate() for comprehensive force plate analysis, analyzeForcePlatePE() for PhysioExperiment-based analysis.

Examples

v <- cbind(
  fp1 = c(rep(0, 100), rep(500, 200), rep(0, 100)),
  fp2 = c(rep(0, 200), rep(700, 100), rep(0, 100))
)
detectForcePlateContacts(v, threshold = 20, sampling_rate = 1000)
#>   plate stance onset offset duration_samples duration_s peak_force
#> 1   fp1      1   101    300              200        0.2        500
#> 2   fp2      1   201    300              100        0.1        700