Centrifugal Effect Model

Implement mathematical representation of centrifugal effect for planetary gravity

  • Library:
  • Aerospace Blockset / Environment / Gravity

  • Centrifugal Effect Model block

Description

The Centrifugal Effect Model block implements the mathematical representation of centrifugal effect for planetary gravity. The gravity centrifugal effect is the acceleration portion of centrifugal force effects due to the rotation of a planet. This block implements this representation using planetary rotation rates. You use centrifugal force values in rotating or non-inertial coordinate systems.

Ports

Input

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Planet-centered planet-fixed coordinates from the center of the planet, specified as a scalar. If Planet model has a value of Earth, this matrix contains Earth-centered Earth-fixed (ECEF) coordinates. The block does not use explicit units.

Data Types: double

Planetary rotation rate, specified as a scalar, in rad/sec.

Dependencies

To enable this parameter, set Planetary rotational rate (rad/sec) to Custom.

Data Types: double

Output

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Gravity values, returned as an m-by-3 array, in the x-axis, y-axis, and z-axis of the planet-centered planet-fixed coordinates, in input distance units per second squared.

Data Types: double

Parameters

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Planetary model, specified as Mercury, Venus, Earth, Moon, Mars, Jupiter, Saturn, Uranus, Neptune, or Custom. The block uses the rotation of the selected planet to implement the mathematical representation of the centrifugal effect.

Dependencies

Selecting Custom enables the Planetary rotational rate (rad/sec) and Input planetary rotation rate parameters.

Programmatic Use

Block Parameter: ptype
Type: character vector
Values: 'Mercury' | 'Venus' | 'Earth' | 'Moon' | 'Mars' | 'Jupiter' | 'Saturn' | 'Uranus' | 'Neptune' | 'Custom'
Default: 'Earth'

Planetary rotational rate in radians per second.

If you want to specify the planetary rotational rate as an input to the block, see the Input planetary rotation rate parameter.

Dependencies

Selecting the Input planetary rotation rate check box disables the Planetary rotational rate (rad/sec) parameter.

Programmatic Use

Block Parameter: omega
Type: character vector
Values: '7.2921150e-05' | scalar
Default: '7.2921150e-05'

Select this check box to enable the ω input port. You can then input a planetary rotation rate as a block input.

Dependencies

Selecting this check box enables the ω and disables the Planetary rotational rate (rad/sec) parameter.

Programmatic Use

Block Parameter: rate_loc
Type: character vector
Values: 'off' | 'on'
Default: 'off'

References

[1] Vallado, David. Fundamentals of Astrodynamics and Applications. New York, NY: McGraw-Hill, 1997.

[2] "Department of Defense World Geodetic System 1984, Its Definition and Relationship with Local Geodetic Systems." NIMA TR8350.2.

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using Simulink® Coder™.

Introduced in R2010a