The Pilot trajectory generator, developed by Network Sensing Technologies (NST), is based on a point mass 3 degree-of-freedom (3DOF) simulation to create flight trajectories relative to the WGS84 ellipsoid.
Pilot.exe is a 32-bit C# software application that executes on Windows platforms. Pilot provides a graphical user interface (GUI) to define a sequence of maneuver events to generate a trajectory file. These trajectory files are predominately used by other applications or in studies. Internally, Pilot uses four coordinate systems: Earth-Centered, Earth-Fixed (ECEF), North-West-Up (NWU), North-East-Down (NED) and Body. All coordinate systems follow the right-hand rule. Pilot's Bearing and Dive Angle are aligned with the Velocity Vector.
Pilot is not an aircraft model, has no autopilot, no lift/drag metrics, no alpha/beta. It is a mathematical based WGS-84 trajectory development tool suitable for rapid trajectory development, exploration and modification. No, it does not accept waypoints. Conceptually, Pilot allows one to generate a trajectory by specifying the initial position and velocity, attitude of a point mass and define a sequence of maneuver events and rotations that describe the trajectory.
The point mass roll channel can be coupled or uncoupled depending on the desired platform. For a conventional aircraft, a Bank to Turn Mode (BTT) automatically computes roll angles. The Skid-to-Turn (STT) mode sets roll to zero and the User Entered roll mode is just that.
Pilot is not designed for trajectories over the poles for barrel loops. It is direction cosine based and a north-slaved system. Pilot does not implement a wander azimuth so discontinuities will exist at high latitudes. Contact NST if a wander azimuth implementation is desired.
Trajectory segments can be saved to templates and later imported making quick resuse of complicated or commonly used maneuves such as a climbing S-Maneuver.
The Pilot GUI provides an easy method to enter of maneuver events. After each event is entered, Pilot iteratively computes the trajectory attempting to converge the trajectory as specified by maneuver event attributes (velocity, accelerations attitude etc). Although Pilot internally models translational motion only, it exports orientation, angular rate, and angular acceleration data. Pilot assumes that the x-axis of the body frame remains aligned with the x-axis of the velocity vector (no angles-of-attack). Roll angles are created by internal models or from a user-defined time history of roll.
Pilot's Maneuver Editor is Based on Initial Conditions, Prior Maneuver's Final State, (et. al.) Maneuver Type and Selection of a Free Variable with A Final Achieved State Field and the Derivative Field
The Free Variable combo box values are dependent on the maneuver type and selects the free variable (unconstrained variable). Pilot will use the starting conditions for this maneuver, the Final State and the Derivative fields to compute the Free Variable.
For example the Free Variable Selection (the Variable Pilot Computes) per Maneuver Type:
Example of the Manuever Editor Free Variable Selection:
Pilot's Configuration Options Allow for User Selectable Tolerances, Entry Units and Display Units:
As each manuever is entered, Pilot updates the predefined plot displays to allow for instant analysis. Predefined plots are:
The Rise Time Factor configuration file parameter controls smoothing of accelerations and resulting angles. The picture that follows shows the effect of Rise Time Factor values (RTF) on raw roll, smoothed roll and roll accelerations via Bezier curve method. The trajectory is a series of S-Turns with the user entered Rise Time Fraction of .1 to .5 in .1 increments, left to right. (Note the decrease in instantaneous roll acceleration due to smoothing and RTF.)
|4||Altitude||Meters Relative to WGS84|
|5..7||ECEF Vel X,Y,Z||Meters/Seconds|
|8..10||ECEF Accel X,Y,Z||Meters/Second2|
|11.13||Roll, Pitch, Yaw (hdg)||Degrees|
|14..16||Body Rate X,Y,Z||Radians/Second|
|17..18||Angular Accel X,Y,Z||Radians/Second2|
|4||Altitude||Meters Relative to WGS84|
|15..17||Body Rate X,Y,Z||Radians/Second|
|18..20||Angular Accel X,Y,Z||Radians/Second2|
|2..4||ECEF Position X,Y,Z||Meters|
|5..7||ECEF Velocity X,Y,Z||Meters/Seconds - Relative to Earth|
|8..10||ECEF Acceleration X,Y,Z||Meters Relative to Earth|
|11..13||ECEF Jerk X,Y,Z||Meters/Second3|
|14..16||Roll, Pitch, Yaw (hdg)||Degrees|
|17..19||Body Rate X,Y,Z||Radians/Second Relative to an Inertial Frame In Body Cords|
|20..21||Angular Accel X,Y,Z||Radians/Second2 Relative to an Inertial Frame In Body Cords|
Note: Specifications, Capabilities, Features and Availability Subject to Change Without Notice and May Be Restricted to Certain Users.