Attitude motion planning for a spin stabilised disk sail

Craig David Maclean, James Biggs

Research output: Contribution to conferencePaper

Abstract

While solar sails are capable of providing continuous low thrust propulsion the size and flexibility of the sail structure poses difficulties to their attitude control. Rapid slewing of the sail can cause excitation of structural modes, resulting in flexing and oscillation of the sail film and a subsequent loss of performance and decrease in controllability. Disk shaped solar sails are particularly flexible as they have no supporting structure and so these spacecraft must be spun around their major axis to stiffen the sail membrane via the centrifugal force. In addition to stiffening the structure this spin stabilisation also provides gyroscopic stiffness to disturbances, aiding the spacecraft in maintaining its desired attitude. A method is applied which generates smooth reference motions between arbitrary orientations for a spin-stabilised disk sail. The method minimises the sum square of the body rates of the spacecraft, therefore ensuring that the generated attitude slews are slow and smooth, while the spin stabilisation provides gyroscopic stiffness to disturbances. An application of Pontryagin’s maximum principle yields an optimal Hamiltonian which is completely solvable in closed form. The resulting analytical expressions are a function of several free parameters enabling parametric optimisation to be used to provide reference motions which match prescribed boundary conditions on the initial and final configurations. The generated reference motions are utilised in the repointing of a 70m radius spin-stabilised disk solar sail in a heliocentric orbit, with the aim of assessing the feasibility of the motion planning method in terms of the control torques required to track the motions.
LanguageEnglish
PagesArticle IAC-12-C1.9.7
Number of pages9
Publication statusPublished - 1 Oct 2012
Event63rd International Astronautical Congress - Naples, Italy
Duration: 1 Oct 20125 Oct 2012

Conference

Conference63rd International Astronautical Congress
CountryItaly
CityNaples
Period1/10/125/10/12

Fingerprint

Solar sails
Motion planning
Spacecraft
Stabilization
Stiffness
Hamiltonians
Maximum principle
Torque control
Attitude control
Controllability
Propulsion
Orbits
Boundary conditions
Membranes

Keywords

  • solar sail
  • motion planning
  • geometric control

Cite this

Maclean, C. D., & Biggs, J. (2012). Attitude motion planning for a spin stabilised disk sail. Article IAC-12-C1.9.7. Paper presented at 63rd International Astronautical Congress, Naples, Italy.
Maclean, Craig David ; Biggs, James. / Attitude motion planning for a spin stabilised disk sail. Paper presented at 63rd International Astronautical Congress, Naples, Italy.9 p.
@conference{a3867c1c833e47df9a6bff5c569bf132,
title = "Attitude motion planning for a spin stabilised disk sail",
abstract = "While solar sails are capable of providing continuous low thrust propulsion the size and flexibility of the sail structure poses difficulties to their attitude control. Rapid slewing of the sail can cause excitation of structural modes, resulting in flexing and oscillation of the sail film and a subsequent loss of performance and decrease in controllability. Disk shaped solar sails are particularly flexible as they have no supporting structure and so these spacecraft must be spun around their major axis to stiffen the sail membrane via the centrifugal force. In addition to stiffening the structure this spin stabilisation also provides gyroscopic stiffness to disturbances, aiding the spacecraft in maintaining its desired attitude. A method is applied which generates smooth reference motions between arbitrary orientations for a spin-stabilised disk sail. The method minimises the sum square of the body rates of the spacecraft, therefore ensuring that the generated attitude slews are slow and smooth, while the spin stabilisation provides gyroscopic stiffness to disturbances. An application of Pontryagin’s maximum principle yields an optimal Hamiltonian which is completely solvable in closed form. The resulting analytical expressions are a function of several free parameters enabling parametric optimisation to be used to provide reference motions which match prescribed boundary conditions on the initial and final configurations. The generated reference motions are utilised in the repointing of a 70m radius spin-stabilised disk solar sail in a heliocentric orbit, with the aim of assessing the feasibility of the motion planning method in terms of the control torques required to track the motions.",
keywords = "solar sail, motion planning, geometric control",
author = "Maclean, {Craig David} and James Biggs",
year = "2012",
month = "10",
day = "1",
language = "English",
pages = "Article IAC--12--C1.9.7",
note = "63rd International Astronautical Congress ; Conference date: 01-10-2012 Through 05-10-2012",

}

Maclean, CD & Biggs, J 2012, 'Attitude motion planning for a spin stabilised disk sail' Paper presented at 63rd International Astronautical Congress, Naples, Italy, 1/10/12 - 5/10/12, pp. Article IAC-12-C1.9.7.

Attitude motion planning for a spin stabilised disk sail. / Maclean, Craig David; Biggs, James.

2012. Article IAC-12-C1.9.7 Paper presented at 63rd International Astronautical Congress, Naples, Italy.

Research output: Contribution to conferencePaper

TY - CONF

T1 - Attitude motion planning for a spin stabilised disk sail

AU - Maclean, Craig David

AU - Biggs, James

PY - 2012/10/1

Y1 - 2012/10/1

N2 - While solar sails are capable of providing continuous low thrust propulsion the size and flexibility of the sail structure poses difficulties to their attitude control. Rapid slewing of the sail can cause excitation of structural modes, resulting in flexing and oscillation of the sail film and a subsequent loss of performance and decrease in controllability. Disk shaped solar sails are particularly flexible as they have no supporting structure and so these spacecraft must be spun around their major axis to stiffen the sail membrane via the centrifugal force. In addition to stiffening the structure this spin stabilisation also provides gyroscopic stiffness to disturbances, aiding the spacecraft in maintaining its desired attitude. A method is applied which generates smooth reference motions between arbitrary orientations for a spin-stabilised disk sail. The method minimises the sum square of the body rates of the spacecraft, therefore ensuring that the generated attitude slews are slow and smooth, while the spin stabilisation provides gyroscopic stiffness to disturbances. An application of Pontryagin’s maximum principle yields an optimal Hamiltonian which is completely solvable in closed form. The resulting analytical expressions are a function of several free parameters enabling parametric optimisation to be used to provide reference motions which match prescribed boundary conditions on the initial and final configurations. The generated reference motions are utilised in the repointing of a 70m radius spin-stabilised disk solar sail in a heliocentric orbit, with the aim of assessing the feasibility of the motion planning method in terms of the control torques required to track the motions.

AB - While solar sails are capable of providing continuous low thrust propulsion the size and flexibility of the sail structure poses difficulties to their attitude control. Rapid slewing of the sail can cause excitation of structural modes, resulting in flexing and oscillation of the sail film and a subsequent loss of performance and decrease in controllability. Disk shaped solar sails are particularly flexible as they have no supporting structure and so these spacecraft must be spun around their major axis to stiffen the sail membrane via the centrifugal force. In addition to stiffening the structure this spin stabilisation also provides gyroscopic stiffness to disturbances, aiding the spacecraft in maintaining its desired attitude. A method is applied which generates smooth reference motions between arbitrary orientations for a spin-stabilised disk sail. The method minimises the sum square of the body rates of the spacecraft, therefore ensuring that the generated attitude slews are slow and smooth, while the spin stabilisation provides gyroscopic stiffness to disturbances. An application of Pontryagin’s maximum principle yields an optimal Hamiltonian which is completely solvable in closed form. The resulting analytical expressions are a function of several free parameters enabling parametric optimisation to be used to provide reference motions which match prescribed boundary conditions on the initial and final configurations. The generated reference motions are utilised in the repointing of a 70m radius spin-stabilised disk solar sail in a heliocentric orbit, with the aim of assessing the feasibility of the motion planning method in terms of the control torques required to track the motions.

KW - solar sail

KW - motion planning

KW - geometric control

UR - http://www.iac2012.org/

M3 - Paper

SP - Article IAC-12-C1.9.7

ER -

Maclean CD, Biggs J. Attitude motion planning for a spin stabilised disk sail. 2012. Paper presented at 63rd International Astronautical Congress, Naples, Italy.