What's the difference between Pose Measurement and Position Measurement?

Question

I have read a robotic related paper called Estimating SE(3) elements using a dual quaternion based linear Kalman filter, and the author proposed that the equation of position measurement is denoted as:

$\mathbf{a}=\mathbf{R}\mathbf{b}+\mathbf{t}$

where $\mathbf{a}$ is the sensor measurement, $\mathbf{R}$ ∈ SO(3) is the rotation matrix, $\mathbf{b}$ ∈ $\mathbf{R}^{3}$is the point to be transformed and $\mathbf{t}$ ∈ $\mathbf{R}^{3}$ is the translation vector. In an application such as rigid registration of images, $\mathbf{a}$ is the sensed location of points and $\mathbf{b}$ is the corresponding point on the CAD model of the object.

The equation of pose measurement is denoted as:

$\mathbf{AX-XB=0}$

where $\mathbf{A,B}$ are pose-measurements, and the $\mathbf{X}$ is the desired transformation to be estimated.

So is there anyone who know what the difference between pose measurement and position measurement?

Answer 1

referring to your equation $$ \boldsymbol{a}=\boldsymbol{Rb}+\boldsymbol{t} ,$$ the position measurement would be $\boldsymbol{t}$ whilst the orientation measurement would be $\boldsymbol{R}$. These quantities can be obtained in different ways, e.g. position could be measured using GPS while orientation could be obtained using an IMU. I hope this helps,

P.S. feel free to ask further details, I've written my master thesis about a similar estimator.

Answer 2

what you are looking for is written in the paper. Position refers only to x,y,z translational measurements while pose means position and orientation.