improve some docstrings

Author: baggepinnen

src/components.jl

@@ -11,7 +11,7 @@ purple = [0.5019608f0,0.0f0,0.5019608f0,1.0f0]
 """
     ori(frame, varw = false)
 
-Get the orientation of `sys` as a `RotationMatrix` object.
+Get the orientation of `sys` as a `RotationMatrix` object. See also [`get_rot`](@ref). `ori(frame).R` is the rotation matrix that rotates a vector from the world coordinate system to the local frame.
 
 For frames, the orientation is stored in the metadata field of the system as `sys.metadata[:orientation]`.
 

src/frames.jl

@@ -33,6 +33,11 @@ The `Frame` connector has internal variables for
 - `r_0`: The position vector from the world frame to the frame origin, resolved in the world frame
 - `f`: The cut force resolved in the connector frame
 - `tau`: The cut torque resolved in the connector frame
-- Depending on usage, also rotation and rotational velocity variables.
+- Depending on usage, also rotation and rotational velocity variables, accessed using `ori(frame).R` and `ori(frame).w`. The rotation matrix represents the rotation to rotate the world frame into the connector frame
+
+# Parameters
+- `render = false`: If true, the connector is rendered in animations
+- `length = 1.0`: Length of the frame when rendered
+- `radius = 0.1`: Radius of the frame when rendered
 """
 Frame

src/orientation.jl

@@ -382,6 +382,7 @@ The rotation matrix returned, ``R_W^F``, is such that when a vector ``p_F`` expr
 ```math
 p_W = R_W^F  p_F
 ```
+This is the inverse (transpose) of the rotation matrix stored in frame connectors (e.g. `ori(frame).R = get_rot(sol, frame, t)'`).
 
 The columns of ``R_W_F`` indicate are the basis vectors of the frame ``F`` expressed in the world coordinate frame.