Set or convert units on IMU burst data

Methods to attach or convert units on the burst matrices of acc, mag, and gyro vectors. Each method validates that the target unit is dimensionally compatible with its IMU class:

• acc: acceleration units (e.g., "m/s^2", "standard_free_fall")

• mag: magnetic flux density units (e.g., "tesla", "uT", "gauss")

• gyro: angular velocity units (e.g., "rad/s", "degree/s")

To calibrate raw accelerometer values rather than simply attaching or converting units, use acc_calibrate().

Usage

set_imu_units(x, value, ...)

Arguments

x

An acc, mag, or gyro vector.

value

Character specifying the target units (e.g., "m/s^2"). For units in terms of gravitational acceleration, use "standard_free_fall".

...

Unused.

Value

The input vector with units attached to each burst matrix.

See also

acc_calibrate() to calibrate raw acceleration values.

Examples

a <- acc_example()

# Attach units to unitless bursts
set_imu_units(a, "m/s^2")
#> <acceleration[2]>
#> [1] (0.67 0.01 1) [m/s^2]  (0.08 -0.52 1) [m/s^2]
#> # frequency: 20 [Hz]

# Convert between units
a_ms2 <- set_imu_units(a, "m/s^2")
set_imu_units(a_ms2, "standard_free_fall")
#> <acceleration[2]>
#> [1] (0.07 0 0.1) [standard_free_fall]     (0.01 -0.05 0.1) [standard_free_fall]
#> # frequency: 20 [Hz]

# Dimensionally incompatible units error
try(set_imu_units(a, "kg"))
#> Error in set_imu_units_(x, value, reference = "m/s^2", sensor = "acc") : 
#>   kg units not valid for `acc` vector.
#> ℹ Units must be convertible to m/s^2