parameters (described below). The present ground track is used as the track for the trick.
The "Turnaround" column indicates if the manoeuvre results in a course reversal, which impacts how it is used in
AUTO missions. Once the trick is completed, the mode that was being used at the start of the trick is restored. If the mode is CRUISE, its
track and altitude are reset to the values present when the mode is restored. Tricks in AUTO missions require that they be performed between two waypoints to establish
| 31 | Multi Point Roll | length | num points | hold frac | pts to do | No |
Some notes about maneuver arguments (arg1 - arg4):
These are parameters each maneuver requires to execute. For example the length of a roll or radius of a loop (in meters), the number of rolls, the height of the maneuver, etc.
When setting up a multi-point roll, for example, the length is in meters, the number of points is 'how many points should the roll have during 360 degrees', the hold fraction is the amount of the maneuver 'not rolling', and the points to do is how many points do you wish to fly. For example, if we want '2 of 4 point roll' : two points of a four point roll. From upright roll through 90 degrees, pause, and then roll through a further 90 degrees - finishing inverted. And we want the maneuver to happen over 100m, and the pause between points to be 50% of the maneuver length. Then the four arguments would be?
Length = 100, num points = 4, hold fraction = 0.5, pts to do = 2.
Remember, the model is now exiting inverted so the next maneuver must be planned to start from this position.
Note: ID's 202-203 are best flown with a mission start point 150m out from the pilot, with the prior and subsequent mission waypoints in a straight line with the model starting the script flying down wind. ID 201 is best started in the same manner, but the model positioned 100m out from the pilot.
## Adding Schedules
Schedules can be added to those above by creating a text file in the /scripts directory or the root directory on the SD card where the plane_aerobatics.lua script is stored.
An example for the "Airshow" schedule is included as trick72.txt and would be executed as TRIK_ID = 72 via switch or in an AUTO mission command. The schedule will display its "name" when started, and as each trick begins the "message" will sent to the GCS to indicate its start.
Note, that the "straight_align" command is not a trick, but rather a command as to when the next trick is to begin. Its parameter is meters from the
schedules initial entry point. Positive numbers are meters away from that point in the entry direction on the ground track, while negative numbers are in the opposite direction on the track line. If the aircraft is already past that point in the desired direction along the track, the trick will begin immediately.
manoeuvre, then the NAV_SCRIPT_TIME with the trick or schedule ID, a timeout that is long enough to allow the trick or schedule, and then a normal waypoint after the manoeuvre.
There are a number of parameters you can set to adjust the path
tracking. Some of the key parameters are:
- AEROM_ANG_ACCEL : maximum angular acceleration in degrees per second per second. Reduce to give smoother flight, but more lag
- AEROM_ANG_TC : time constant for correcting angular roll errors. Reduce for snappier rolls, but more risk of oscillation
- AEROM_KE_ANG : knifeedge angle. This is the required pitch angle in knifeedge flight to hold height at cruise speed.
- AEROM_ENTRY_RATE : roll rate in degrees per second for entering and exiting a roll change
- AEROM_THR_MIN : minumum throttle percentage for all aerobatic maneuvers
- AEROM_THR_BOOST: minumum throttle percentage for maneuvers marked as throttle boost
- AEROM_YAW_ACCEL: maximum yaw acceleration in degrees per second per second. Lower to soften yaw control
- AEROM_PATH_SCALE: scale factor for all maneuvers. A value above 1.0 will increase the size of the maneuvers. A value below 1.0 will decrease the size. A negative value will mirror the maneuvers, allowing a sequence designed for left-to-right to be flown right-to-left.
