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insMotionOrientation

Motion model for 3-D orientation estimation

Since R2022a

Description

The insMotionOrientation object models orientation-only platform motion assuming a constant angular velocity. Passing an insMotionOrientation object to an insEKF object enables the estimation of 3-D orientation and angular velocity. For details on the motion model, see Algorithms.

Creation

Description

model = insMotionOrientation creates an insMotionOrientation object. Passing the created 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.

example

Examples

collapse all

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

motionModel = insMotionOrientation
motionModel = 
  insMotionOrientation with no properties.

filter = insEKF(motionModel)
filter = 
  insEKF with properties:

                   State: [7x1 double]
         StateCovariance: [7x7 double]
    AdditiveProcessNoise: [7x7 double]
             MotionModel: [1x1 insMotionOrientation]
                 Sensors: {}
             SensorNames: {1x0 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]

Algorithms

The insMotionOrientation object models the orientation-only motion of platforms. The state equation of the motion model is:

q˙=12ωqω˙=0

where:

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

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

Version History

Introduced in R2022a