‘imuf’ uses complementary filtering to estimate the orientation of aninertial measurement unit (IMU) with a 3-axis accelerometer and a 3-axisgyroscope. It takes the IMU’s accelerometer and gyroscope readings, timeduration, its initial orientation, and a ‘gain’ factor as inputs, andprovides an estimate of the final orientation as outputs.
‘imuf’ adopts the north-east-down (NED) coordinate system. Theinitial and final orientations are expressed as quaternions in (w, x, y,z) convention.
install.packages("imuf")You can install the development version of imuf fromGitHub with:
# install.packages("pak")pak::pak("gitboosting/imuf")This is a basic example which shows you how to solve a commonproblem:
library(imuf)#acc<-c(0,0,-1)# accelerometer NED readings in g (~ 9.81 m/s^2)gyr<-c(1,0,0)# gyroscope NED readings in radians per seconddeltat<-0.1# time duration in secondsinitq<-c(1,0,0,0)# initial orientation expressed as a quaterniongain<-0.1# a weight (0-1) given to the accelerometer readings## final orientation expressed as a quaternion(final<-compUpdate(acc, gyr, deltat, initq, gain))#> [1] 0.99898767 0.04498481 0.00000000 0.00000000### rotate a vector pointing east by 90 deg about northq<-c(cos(pi/4),sin(pi/4),0,0)# quaternion to rotate 90 deg about northvin<-c(0,1,0)# vector in east direction(vout<-rotV(q, vin))# after rotation, vector is in down direction#> [1] 0.000000e+00 2.220446e-16 1.000000e+00