EKF Initialization via Spoof

After successful integration of the Cyclops system, you will see the position of the drone on Mission Planner is centered at the coordinate 0 N 0 E. This is because the EKF can only initialize if a position is injected on the ground. To initialize the EKF, Cyclops has a built-in spoof mapped to channel 6 on your RC (RC6) by default.

Setup

In Mission Planner and on your RC, map a switch to RC6.

Procedure

The spoof lasts for 15 seconds. It is very important to not move the drone while the spoof is active, as it will cause EKF invariance.

In simple terms, the spoof initialization procedure is as follows:

BEGIN SPOOF -> ARM -> SPOOF ENDS -> LAUNCH

Step 1:

Place your drone on the ground at the launch point. Power the drone on.

Step 2:

Flip the switch mapped to RC6. On your GCS you will see the message:

SRC=1/191:VPS HOME SPOOF ACTIVE
EKF3 IMU ORIGIN SET
GPS 2:DETECTED MAV
FIELD ELEVATION SET: (x)M 

It is normal to see other messages as the EKF initializes.

Step 3:

Now you must ARM the system on the ground. Do not take off until you see this message:

SRC=1/191:VPS HOME SPOOF ENDED

It is best to Arm the system while the spoof is active, as arming can reset the altitude and cause the system to produce bad altitude readings.

Moving the drone while the EKF is initializing can cause very unexpected behavior and is generally harmful for the EKF.

Step 4:

Once the spoof ends you may launch. Cyclops will initialize when it reaches 20m AGL and the position will update on the GCS.

The position may return to 0 N 0 E after the spoof ends. This is normal and will update once Cyclops reaches 20m AGL.