AirshipAutopilot:
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Autopilot for an airship.
Given the desired trajectory and the current measured state, compute the
body-frame velocity and angular rate commands for the controllers.
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Form:
cmd = AirshipAutopilot( action, data )
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Inputs
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action (:) String name of action to take. Choices are:
* 'reset' ... Reset the commands to current states
* 'set limits' ... Supply rate limits
* 'set dt' ... Supply the time step
* 'update' ... Update the commands
data (.) Data required for action
if action == 'reset'
(when no data provided, sets all to 0)
- data.u ... current axial velocity [m/s]
- data.v ... current lateral velocity [m/s]
- data.w ... current normal velocity [m/s]
- data.p ... current roll rate [rad/s]
- data.q ... current pitch rate [rad/s]
- data.r ... current yaw rate [rad/s]
if action == 'set limits'
- data.u ... rate limit, axial velocity [m/s/s]
- data.v ... rate limit, lateral velocity [m/s/s]
- data.w ... rate limit, normal velocity [m/s/s]
- data.p ... rate limit, roll rate [rad/s/s]
- data.q ... rate limit, pitch rate [rad/s/s]
- data.r ... rate limit, yaw rate [rad/s/s]
if action == 'set dt'
- data ... time-step [sec]
if action == 'update'
- trajDes ... desired trajectory data (psi,theta,vel)
- trajMeas ... measured trajectory data (psi,theta,vel)
- stateMeas ... measured state data (p,q,r,u,v,w)
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Outputs
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cmd (.) Data structure of commanded rates
- cmd.u ... Axial velocity command [m/s]
- cmd.v ... Lateral velocity command [m/s]
- cmd.w ... Normal velocity command [m/s]
- cmd.p ... Roll rate command [rad/s]
- cmd.q ... Pitch rate command [rad/s]
- cmd.r ... Yaw rate command [rad/s]
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Children:
Common: Control/Limit
Math: Trigonometry/WrapPhase
