insMotionPose

Model for 3-D motion estimation

Since R2022a

Description

The insMotionPose object models 3-D motion assuming constant angular velocity and constant linear acceleration. Passing an insMotionPose object to an insEKF object enables the estimation of 3-D motion, including orientation, angular velocity, position, linear velocity, and linear acceleration. For details on the motion model, see Algorithms.

Creation

Syntax

model = insMotionPose

Description

model = insMotionPose creates an insMotionPose object. Passing model to an insEKF object enables the estimation of:

• The orientation quaternion from the navigation frame to the body frame.

• The angular velocity of the platform, expressed in the body frame.

• The position of the platform, expressed in the navigation frame.

• The velocity of the platform, expressed in the navigation frame.

• The acceleration of the platform, expressed in the navigation frame.

Examples

Create insMotionPose for Use in insEKF

Create an insMotionPose object and pass it to an insEKF object.

motionModel = insMotionPose

motionModel = 
  insMotionPose with no properties.

filter = insEKF(motionModel)

filter = 
  insEKF with properties:

                   State: [16×1 double]
         StateCovariance: [16×16 double]
    AdditiveProcessNoise: [16×16 double]
             MotionModel: [1×1 insMotionPose]
                 Sensors: {}
             SensorNames: {1×0 cell}
          ReferenceFrame: 'NED'

Show the state maintained in the filter.

stateinfo(filter)

ans = struct with fields:
        Orientation: [1 2 3 4]
    AngularVelocity: [5 6 7]
           Position: [8 9 10]
           Velocity: [11 12 13]
       Acceleration: [14 15 16]

Algorithms

The insMotionPose object models the motion of platforms. The state equation of the motion model is:

$$\begin{array}{l}\dot{q}=\frac{1}{2}q\omega \\ \dot{\omega }=0\\ \dot{p}=v\\ \dot{v}=a\\ \dot{a}=0\end{array}$$

where:

• q = (q₀, q₁, q₂, q₃) is the quaternion from the navigation frame to the body frame.

• ω = (0, ω_x, ω_y, ω_z) is the angular velocity of the platform, expressed in the body frame.

• p is the position of the platform, expressed in the navigation frame.

• v is the linear velocity of the platform, expressed in the navigation frame.

• a is the linear acceleration of the platform, expressed in the navigation frame.

Version History

Introduced in R2022a