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Mission Flight

AutoQuad is born to perform mission flights. But first a statement about safety:

The AutoQuad is able to perform autonomous missions.Please observe (local) regulations like maximum altitude, safe distances to populated areas and traffic. Never loose sight of the aircraft, use a spotter when flying (autonomous) FPV missions. Never plan missions directly over attended audience. In general, use common sense when planning a mission.There are (currently) no restrictions build into the system and being opensource the code could easily removed anyway

AutoQuad is capable of performing the following mission commands:

Command Minimum firmware Explanation
take off 6.6 take off to a settable height above ground with settable vertical speed, perform a ‘loiter’ for a settable time
land 6.6 land at GPS position with settable descend speed
waypoint 6.1 Go-To GPS location, settable altitude, settable horizontal speed, settable wait time
return to home 6.1 Execute a return to the stored home position at stored altitude with pre-defined horizontal speed
orbit 6.6 Execute an orbital flight around a GPS point, settable radius, settable horizontal (orbital) speed, settable altitude

The orbit command has additional features; it will keep the heading (front of multirotor) pointed to the center and if the altitude of the point of interest and altitude of the AutoQuad is different, it will keep the camera gimbal tilted to the altitude of point of interest. This will provide a great way to circle around an object while keeping the camera pointed to the object.

Missions can be created, uploaded, retrieved and stored offline using the Ground control station(s). It is even possible to load or store them on the uSD card so missions can be created at home.

There are no limits in the mission waypoints, no altitude or position distances. Currently there is a 25 waypoint limit in the code because we simple don’t know yet the flash limitations for storing complex missions. The limit can obviously be changed in the firmware code for developers.

Create a Mission

Missions can be created using the GroundControl station windows or the Android GCS. Both the GCS types will allow to place a waypoint somewhere on the map, select the type and upload the mission plan to the AutoQuad flightcontroller. In this example we concentrate on the windows GCS.

First connect to the AutoQuad flightcontroller using the FTDI interface. Obviously connecting with a bluetooth or Xbee device to upload/retrieve the mission is possible.

Place a waypoint on the map using the mouse and select the type in the menu. You can move waypoints sequence in the list, edit them or delete them.

Forum discussion: Step by Step mission planning via PC QGC

Upload / retrieve a Mission

Once satisfied you can use the write button to upload the mission to the AutoQuad flightcontroller. The buttons Save/Load WP will create or load an offline file with the created mission. Retrieving a stored mission can be done with the read button.

A mission is store in volatile memory, it will be lost after a power cycle or reboot.

Store on uSD

Using the Groundcontrol station(s) an option is available to store a just created mission on the AutoQuad onboard uSD. For that a uSD must be placed in the AutoQuad flight controller. Inserting the card will trigger the log function but an store command from the ground control stations will cause the waypoint list to be stored on the uSD card. This is also available on the Android GCS in the mission planner menu.

For the windows GCS select the engineer tab, AutoQuad widget.

Here you will find the ‘All parameter widget’ with two buttons: WP from SD and WP to SD for loading the missionplan or saving the mission plan to the uSD card.

Execute the Mission

Most of the missions will be engaged while in flight, either a hover or position hold. The mission is a sequential set of commands and will simply start at command 1. After all commands in the queue are done the mission will transition into position hold. Start a mission by switching to the mission mode ( aux 2 ) and center throttle stick . Below or above center will command an ascend or descend of the multirotor. Don’t worry about the precise midpoint, a default deadband around center of 35us will give you a neutral zone around center where nothing will happen. If that is to narrow, you can increase the deadband parameter in the configuration.

Failsafe events during mission: during the execution of the mission, a radio loss signal is ignored until the last mission command is executed.

Abort an Mission

At any time during the mission you can abort the execution by switching to manual mode. At that time the radio fail safe event is also active again.

Take off Command

Once stored in the AQ as a takeoff command, a special sequence is needed to execute this command and the next mission commands. Start with the multirotor on the ground, arm the AutoQuad, switch to mission mode ( AUX2 – mission mode ) and.. this is very important, center the throttle stick. Without centering, the navigation routine will think it is in descending command, every mission should be flown with the throttle in center position. Because the throttle commands altitude change in navigation modes, a throttle not in center will command ascending or descending.

Parameters in Mission Commands

Number P1 P2 P3 P4 P5 P6 P7
Description Latitude Longitude Altitude Delay Hit Radius Yaw Angle Free
Units       ms meter degree  
  Go to Home      
Number P1 P2 P3 P4 P5 P6 P7
Description Free Free Free loiter Time Hit Radius Free Free
Units       ms meter    
  TAKE OFF            
Number P1 P2 P3 P4 P5 P6 P7
Description MaxHorizSpeed Hit Radius Poi Heading loiterTime Target Alt Free Free
Units m/sec meter degree ms meter (absolut)    
Number P1 P2 P3 P4 P5 P6 P7
Description MaxHorizSpeed Free Free Free Free Free PoiAltitude
Units m/sec           meter
Number P1 P2 P3 P4 P5 P6 P7
Description Latitude Longitude target Altitude MaxHorizSpeed Hit Radius loiterTime Poi Heading
Units     meter m/sec meter ms degree

Troubleshooting and Tips for autonomous Flights

Problem: when sending the copter on a mission with several waypoints it seems to stop after the first WP is reached.
Solution: If you selected a too small value for the target radius (Hit Rad.) the aircraft tries to  reach the exact point. Especially under windy conditions it might take long until it hits the position precisely. Set the “Hit Rad.” to 2m or more like shown in the image below. The delay should disappear then and the copter will always continue its flight to the next WP.

Problem: the copter doesn’t turn towards the waypoint on a mission flight but keeps the heading i.e. flying sidewards.
Solution: Select a negative value in the Yaw box, like -1.0

This page was created on 18-Jun-12 by menno. Last modified on 20-Oct-15 by kinderkram.