Instrumented Nine-Hole-Peg dexterity from a hand-speed profile

Turns the hand-speed profile of a peg-transport task (the Nine-Hole-Peg Test of fine hand use) into instrumented dexterity metrics: the number of detected peg transports (speed peaks), the transport rate, the mean and coefficient of variation of the inter-transport intervals (movement consistency) and the overall smoothness. This is the sensor-derived complement to the clinical timed NHPT score, and realises ICF d440 (fine hand use).

Usage

nhptDexterity(speed, sampling_rate, ...)

Arguments

speed: Numeric hand speed profile over the whole task.
sampling_rate: Sampling rate in Hz.
...: Passed to movementUnits() (peak height/prominence controls).

Value

an nhpt_dexterity list: icf_code, n_transports, total_time, transport_rate (transports/s), mean_interval, cv_interval (interval consistency) and smoothness (SPARC).

References

Mathiowetz V, et al. (1985) Am J Occup Ther 39:386-391 (NHPT).

Examples

fs <- 100
bell <- function(n) { u <- seq(0, 1, length.out = n); 30 * u^2 * (1 - u)^2 }
# nine evenly spaced transports
v <- unlist(replicate(9, c(bell(40), numeric(20)), simplify = FALSE))
nhptDexterity(v, fs)$n_transports
#> [1] 9