orient_feather {AvInertia} R Documentation

## Determine the feather orientation

### Description

Code that returns the orientation of each primary and secondary feather on the wing.

### Usage

```orient_feather(no_pri, no_sec, Pt1, Pt2, Pt3, Pt4, Pt8, Pt9, Pt10, Pt11, Pt12)
```

### Arguments

 `no_pri` a scalar representing the amount of primary feathers. `no_sec` a scalar representing the amount of secondary feathers. `Pt1` a 1x3 vector (x,y,z) representing the point on the shoulder joint (m). `Pt2` a 1x3 vector (x,y,z) representing the point on the elbow joint (m). `Pt3` a 1x3 vector (x,y,z) representing the point on the wrist joint (m). `Pt4` a 1x3 vector (x,y,z) representing the point on the end of carpometacarpus (m). `Pt8` a 1x3 vector (x,y,z) representing the point on tip of most distal primary (m). `Pt9` a 1x3 vector (x,y,z) representing the point on the tip of the last primary to model as if it is on the end of the carpometacarpus (m). `Pt10` 1x3 vector (x,y,z) representing the point on tip of last primary to model as if it was distributed along the carpometacarpus (m). Usually the first secondary feather tip. `Pt11` 1x3 vector (x,y,z) representing the point on tip of most proximal secondary feather (m). `Pt12` 1x3 vector (x,y,z) representing the point on exterior shoulder position (wing root leading edge) (m).

### Value

a list called "feather". This contains three matrices.

1. "loc_start" a matrix defining the 3D point where each feather starts. Rows are the different feathers and columns are x, y, z coordinates respectively.

2. "loc_end" a matrix defining the 3D point where each feather end. Rows are the different feathers and columns are x, y, z coordinates respectively.

3. "normal" a matrix that gives the vector that defines the normal to each feather plane. Rows are the different feathers and columns are x, y, z vector directions respectively.

Christina Harvey

### Examples

```# refer to the vignette
library(AvInertia)

data(dat_id_curr, package = "AvInertia")
data(dat_bird_curr, package = "AvInertia")
data(dat_feat_curr, package = "AvInertia")
data(dat_bone_curr, package = "AvInertia")
data(dat_mat, package = "AvInertia")
data(clean_pts, package = "AvInertia")

# 1. Determine the center of gravity of the bird's torso (including the legs)
dat_torsotail_out = massprop_restbody(dat_id_curr, dat_bird_curr)
# 2. Calculate the inertia of the flight feathers about the tip of the calamus
feather_inertia <- compute_feat_inertia(dat_mat, dat_feat_curr, dat_bird_curr)
# 3. Determine the center of gravity of one of the bird's wings
dat_wing_out      = massprop_birdwing(dat_id_curr, dat_bird_curr,
dat_bone_curr, dat_feat_curr, dat_mat, clean_pts,
feather_inertia, plot_var = 0)
# Visualize the center of gravity of each wing component in the x and y axis
dat_wing_out      = massprop_birdwing(dat_id_curr, dat_bird_curr,
dat_bone_curr, dat_feat_curr, dat_mat, clean_pts,
feather_inertia, plot_var = "yx")
# or the y and z axis
dat_wing_out      = massprop_birdwing(dat_id_curr, dat_bird_curr,
dat_bone_curr, dat_feat_curr, dat_mat, clean_pts,
feather_inertia, plot_var = "yz")
# 4. Combine all data and obtain the center of gravity, moment of inertia
# and principal axes of the bird
curr_full_bird      = combine_inertialprop(dat_torsotail_out,dat_wing_out,
dat_wing_out, dat_id_curr, dat_bird_curr, symmetric=TRUE)

```

[Package AvInertia version 0.0.1 Index]