Abstract
The trajectory and attitude dynamics of an orbital spacecraft are defined by a unified state model, which enables efficient and rapid machine computation for mission analysis, orbit determination and prediction, satellite geodesy and reentry analysis. The state variables are momenta — a general form for attitude, and a parametric form for orbital motion. The orbital parameters are the velocity state characteristics of the orbital hodograph. The coordinate variables are sets of four Euler parameters, which define the rotation transformation by the quaternion algebra.
The unified state model possesses many analytical properties which are invaluable for dynamical system synthesis, numerical analysis and machine solution: regularization, unified matrix algebra, state graphs and transforms. The analytic partials of position and velocity with the state and coordinate variables are presented, as well as representative perturbation functions such as air drag, gravitational potential harmonics, and propulsion thrust.
Similar content being viewed by others
Abbreviations
- A :
-
wind cross-section of orbital body
- Az :
-
direction of the wind velocityq in the local horizon plane, referred to the projection of the Z-axis on that plane
- C, R :
-
parametric variables of orbital velocity state
- C D :
-
drag coefficient of orbital body
- C 22,S 22 :
-
coefficients of the cos and sin terms (respectively) of the tesseral harmonics for the gravitational potential function (m=n=2)
- [E]:
-
transformation matrix of body attitude rotation, with elementsɛ ij
- e 1,e 2,e 3 :
-
rotating polar set of unit vectors defining the point-mass motion about the planetocentric origin 0
- e 1,e 2,e 3,e 4 :
-
Euler parameters defining rotation of a coordinate set
- e a1,e a2,e a3,e a4 :
-
Euler parameters defining attitude rotation of the orbital body about its center-of-mass
- e 01,e 02,e 03,e 04 :
-
Euler parameters defining rotation of the orbital trajectory frame about the planetocentric origin 0
- f 1,f 2,f 3 :
-
intermediate set of unit vectors defining coordinates in the instantaneous orbital plane, referred to axisX′
- g 1,g 2,g 3 :
-
planetocentric inertial set of unit vectors fixed in inertial space about the planetocentric origin 0
- [H]:
-
angular momentum matrix of the body attitude dynamics
- [J]:
-
inertia matrix of the orbital body, with elementsJ ij
- J 2,J 3,J 4 :
-
coefficients of the zonal harmonics for the gravitational potential function (n=2, 3, 4 respectively)
- Lo, La :
-
topocentric coordinates of longitude and latitude, respectively
- m :
-
mass of the orbital body
- g :
-
a unitary quaternion
- q :
-
atmospheric wind velocity in the local horizon plane
- R e :
-
spherical Earth's radius
- r, v, α,J :
-
position, velocity, acceleration and jerk (i.e., time-rate of acceleration change) vectors of orbital motion, respectively
- T :
-
torque vector of attitude perturbation
- u :
-
angle of rotation of a coordinate set about a directed axis whose points are invariant
- v r :
-
relative velocity
- w x, wy, wz :
-
angular velocity of the body attitude rotation about its principal axes
- w 1,w 3 :
-
angular velocity of the rotating polar coordinates of the orbital body motion about the planetocentric origin 0
- α, β, γ:
-
direction angles defining space orientation of a directed line
- δ:
-
angle of rotation of the axisX about the line-of-nodesLN, to axisX′ in the instantaneous orbital plane
- ζ:
-
square of the Mach number for the orbital velocity at the given altitude
- η:
-
constant (ζ/r) assumed in the exponential model of atmospheric density as a function of altitude
- θ:
-
flight path angle (i.e., angle between the orbital velocity vector and the local horizon in the instantaneous orbital plane)
- ι:
-
angle of incidence between the instantaneous orbital plane and the equatorial planeXY
- λ:
-
angle of rotation from the axisX′ to the orbital position vectorr, in the instantaneous orbital plane
- μ:
-
planetary gravitational constant
- ν≡ui:
-
angle from the line-of-nodesLN to the orbital position vectorr
- ϱ:
-
atmospheric density
- ϱ0:
-
atmospheric density at sea level
- ϕ:
-
true anomaly
- σ:
-
angle of rotation from the axisX′ to the perigee apsis
- Ω:
-
angle from the inertial axisX to the line-of-nodesLN
- ω e :
-
planetary rate of rotation about its spin axisZ
- B :
-
orbital body axes
- b :
-
ballistic
- e1,e2,e3:
-
rotating polar coordinate components of orbital motion
- f1,f2:
-
intermediate coordinate components of orbital motion
- I :
-
inertial axes
- T1,T2,T3,T4:
-
Euler parameter components of the topocentric coordinates
References
Altman, S. P.: 1966, inRecent Developments in Space Flight Mechanics, Vol.9, AAS Science and Technology Series, AAS Publications Office, Tarzana, Calif., pp. 45–102.
Acceleration Hodograph Analysis Techniques for Powered Orbital Trajectories, NASA Contractor Report CR-61615, June 1967.
Altman, S. P. and Pistiner, J. S.: 1968, ‘Application of State Space Transformation Theory to Orbit Determination and Prediction’, AAS Paper No. 68-111, AAS/AIAA Astrodynamics Specialist Conference, Jackson, Wyoming, September 3–5.
Tapley, B. D., Szebehely, V., and Lewallen, J. M.: 1968, ‘Trajectory Optimization Using Regularized Variables’, AAS Paper No. 68-099, AAS/AIAA Astrodynamics Specialist Conference, Jackson, Wyoming, September 3–5.
Lewallen, J. M., Schwausch, O. A., and Tapley, B. D.: 1969, ‘Coordinate System Influence on the Regularized Trajectory Optimization Problem’, AIAA Paper No. 69-903, AIAA/AAS Astrodynamics Conference, Princeton, New Jersey, August 20–22.
Wilcox, J. C.: 1967,IEEE Transactions on Aerospace and Electronic Systems, VolumeAES-3, No. 5, pp. 796–802.
Jackson, D. B.: 1969,Proceedings of the Symposium on Spacecraft Attitude Determination, The Aerospace Corporation, September 30/October 1–2, 1969, pp. 89–111.
Toda, N. F., Heiss, J. L., and Schlee, F. H.: 1969, ‘SPARS; The System, Algorithms and Test Results’,Proceedings of the Symposium on Spacecraft Attitude Determination, The Aerospace Corporation, September 30/October 1–2, 1969, pp. 361–370.
Ickes, B. P.: 1970,AIAA J. 8, pp. 13–17.
Sir William Rowan Hamilton: 1966,Elements of Quaternions, Volumes I and II, (ed. by C. J. Joly), reprint by Chelsea Publishing Company, New York, 1969.
Larson, R. E., Dressler, R. M., and Ratner, R. S.: ‘Precomputation of the Weighting Matrix in an Extended Kalman Filter’, Stanford Research Institute, Menlo Park, California, publication and date unknown.
Broglio, L.: 1964,AIAA J. 2, 1774–1781.
Research Study on the Acceleration Hodograph and Its Application to Space Trajectory Analysis, NASA Contractor Report CR-19, September 1963.
Arsenault, J. L., Ford, K. C., and Koskela, P. E.: 1970,AIAA J. 8, 4–12.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Altman, S.P. A unified state model of orbital trajectory and attitude dynamics. Celestial Mechanics 6, 425–446 (1972). https://doi.org/10.1007/BF01227757
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF01227757