calculate.kinematic: This function corrects translation of the direct kinematic...

In browarsoftware/RMoCap: Package for processing and kinematic analyzing motion capture data.

Description

This heuristic method is especially usable while dealing with data acquired by IMU (Inertial measurement unit) sensors. There are two possible calls of this method. The first one utilize acceleration data of body joints (.ax, .ay and .az columns). If this data is available method can calculate displacement of long motion, during which an actor uses both left and right leg. If this call is used, one should left bodypartname as NULL. The second call is used when we are dealing with data without acceleration data and actor has one stationary limb. In this case bodypartname should have value of the limb which does not translate during motion.

Usage

calculate.kinematic(dd, LeftFoot = "LeftFoot", RightFoot = "RightFoot",
  show.plot = FALSE, plot.title = "", bodypartname = NULL, dyEps = 5)

Arguments

dd	data frame with motion capture data.
LeftFoot	name of the column with data that holds coordinates of left foot (joint that touch the ground). Default value is LeftFoot = "LeftFoot". Used only for the first type of call.
RightFoot	name of the column with data that holds coordinates of right foot (joint that touch the ground). Default value is RightFoot = "RightFoot". Used only for the first type of call.
show.plot	if TRUE (default is show.plot = FALSE) plots results of an algorithm.
plot.title	part of the title over plots.
bodypartname	if not NULL value the stationary joint of the motion is column with bodypartname. Default value is bodypartname = NULL.
dyEps	Threshold value for translation calculation (used only for the first type of call). Default value is dyEps = 5.

Value

Data frame, which has Dxzy columns updated. All other columns are not updated.

Examples

  #This example uses acceleration data to calculates correct displacement.
  #header of mocap file
  data("header.mocap")
  #data frame with displacements and acceleration data
  data("heian.shodan")

  heian.shodan.corrected <- calculate.kinematic(heian.shodan, show.plot = "TRUE", plot.title = "Heian Shodan")
  original.bvh <- set.data.frame(header.mocap, heian.shodan)
  corrected.bvh <- set.data.frame(header.mocap, heian.shodan.corrected)
  #plot BVH, red is original data, green is corrected
  plot(original.bvh, frames.fraction = 0.1, my.color = "red", alpha = 0.1, spheres = FALSE)
  plot(corrected.bvh, frames.fraction = 0.1, my.color = "green", alpha = 0.1, spheres = FALSE, append = TRUE)

  #writing BVH to disk
  write.bvh(original.bvh, "original.bvh")
  write.bvh(corrected.bvh, "corrected.bvh")

  #This example uses single body joint which coordinates should be constant during motion
  data(mawashi.geri.left.1)
  plot(mawashi.geri.left.1, frames.fraction = 0.1, my.color = "red", alpha = 0.5, spheres = FALSE)
  mawashi.geri.left.1$data.frame <- calculate.kinematic(mawashi.geri.left.1$data.frame, bodypartname = "RightFoot")
  plot(mawashi.geri.left.1, frames.fraction = 0.1, my.color = "green", alpha = 0.5, spheres = FALSE, append = TRUE)

browarsoftware/RMoCap documentation built on May 16, 2019, 7:28 a.m.