midas.nav.guide

MIDAS guidance (midas.nav.guide)

This is the midas.nav module for implementation of the Guidance block in a navigation analysis.

The Guidance takes the estimated state distribution from the Estimator that is known at the commanding epoch before the manoeuvre execution. The Guidance then performs a computation, e.g., a linearised guidance computation or a Monte Carlo optimisation, to compute the commanded control parameters. It is possible to command one or multiple manoeuvres at each commanding cycle.

The result of the Guidance are the commanded control parameters distribution at the commanding epoch, which is then passed to the ErrorSimulator to simulate the manoeuvre execution errors and, finally, the executed control parameters distribution is passed to the Simulator that propagates the state and parameters distribution to the next commanding opportunity (or end of mission).

Guidance

The Guidance base class defines the methods to be implemented by any guidance algorithm.

Guidance()

An abstract class that defines the guidance interface.

Linear Guidance

The LinearGuidance algorithm implemented in MIDAS simulates the manoeuvre optimisation and tries to correct the deviation on some state representation of the state (e.g., b-plane parameters) at some future point in time (e.g., TCA or entry point) from the nominal trajectory. This allows commanding multiple manoeuvres at the same time but does not attempt to minimise delta-V expenditure.

LinearGuidance(targets, controls, ...[, ...])

LinearGuidance class.

The LinearGuidance requires as input a list of Targets, which define the central body, spacecraft and epoch of all available targets, and a list of Controls, which define the manoeuvres to be commanded at each commanding epoch and their respective Targets and TargetedStates.

Target(name, epoch, body, spacecraft)	Target configuration to pass to LinearGuidance.
TargetedState(name, variables[, axes, ...])	Targeted state configuration to pass to Control.
Control(name, epoch, targeted_states, ...)	Control configuration to pass to LinearGuidance.