> For the complete documentation index, see [llms.txt](https://docs.theseus.us/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.theseus.us/cyclops/autopilot-integration/ardupilot/cyclops-v2.x.x/ekf-initialization-via-spoof.md).

# 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, we have shipped a spoof which is mapped to RC Channel 6.

## Setup

In Mission Planner and on your RC, configure a switch to map to RC Channel 6.

## Procedure

{% hint style="info" %}
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.
{% endhint %}

### Step 1:

Flip the switch that you have configured to channel 6. You should now see the message:

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

### Step 2:

Now you must ARM the system, but do not take off until you see this message:

```
SRC=1/191:VPS HOME SPOOF ENDED
```

{% hint style="info" %}
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.
{% endhint %}

{% hint style="danger" %}
Moving the drone while the EKF is initializing can cause very unexpected behavior and is generally harmful for the EKF.
{% endhint %}

### Step 3:

Take off. At 20m AGL, Cyclops will initialize and you will start to see the position updating live in Mission Planner.