Manual Relocalization

If you are flying with cyclops in the loop but have some additional information (maybe visual information, or a GPS fix) you may want to reset the cyclops and ekf position to that new ground truth. You can do that when connected the the drone over mavlink with vozilla.

Just right click on the map while connected over mavlink and click "Relocalize here" to move the EKF and cyclops to the point you clicked. It also resets cyclops and can be useful if scale or heading estimation is offset.

Overview

Cyclops can accept a manual relocalize command over MAVLink. Send a targeted COMMAND_INT using command id 43003 (MAV_CMD_EXTERNAL_POSITION_ESTIMATE) with the new WGS84 latitude and longitude. When accepted, Cyclops synchronously resets its map-match position state to that coordinate.

Use COMMAND_INT, not COMMAND_LONG, so latitude and longitude are carried as degE7 integers instead of lossy float32 values.

Target

Target the Cyclops MAVLink identity:

Field	Default	Source
target_system	218	mavproxy.source_system
target_component	191	mavproxy.mvps_compid

Read the deployed values with:

vns-config get mavproxy.source_system
vns-config get mavproxy.mvps_compid

The command must arrive on a MAVLink path that Cyclops receives. For autopilot Lua scripts, send it from the flight controller. For external test clients using MAVProxy, add a temporary upstream endpoint and restart MAVProxy:

vns-config add mavproxy.device udpin:0.0.0.0:14610
sudo systemctl restart mavproxy

The standard external GCS output is not forwarded to other MAVProxy outputs, so it is not a reliable path for commands targeted at Cyclops.

COMMAND_INT Fields

Field	Value
command	43003 (MAV_CMD_EXTERNAL_POSITION_ESTIMATE)
frame	MAV_FRAME_GLOBAL (0)
current	0
autocontinue	0
param1	0 for a reset request
param2	0
param3	Optional accuracy in meters; 0 is accepted
param4	0
x	Latitude in degE7, e.g. 37.4221234 -> 374221234
y	Longitude in degE7, e.g. -122.0839876 -> -1220839876
z	NaN; altitude is not used for the reset

Cyclops validates that latitude and longitude are finite and inside normal WGS84 bounds. The target must also be inside the loaded map area.

Response

Cyclops replies with COMMAND_ACK for command 43003:

Result	Meaning
MAV_RESULT_ACCEPTED	Reset succeeded.
MAV_RESULT_TEMPORARILY_REJECTED	Cyclops is already relocalizing. Retry later.
MAV_RESULT_FAILED	Coordinates are invalid, outside the map, or the map matcher is unavailable.

After an accepted reset, Cyclops also publishes a GLOBAL_POSITION_INT confirmation at the reset coordinate. Normal map matching resumes after the first post-reset odometry sample refreshes the displacement baseline.

pymavlink Example

import math
from pymavlink import mavutil

MAV_CMD_EXTERNAL_POSITION_ESTIMATE = 43003

lat = 37.4221234
lon = -122.0839876

master = mavutil.mavlink_connection("udpout:192.168.218.100:14610")
master.mav.command_int_send(
    218,  # target_system: mavproxy.source_system
    191,  # target_component: mavproxy.mvps_compid
    mavutil.mavlink.MAV_FRAME_GLOBAL,
    MAV_CMD_EXTERNAL_POSITION_ESTIMATE,
    0,  # current
    0,  # autocontinue
    0,  # param1: reset request
    0,  # param2
    0,  # param3: optional accuracy_m
    0,  # param4
    round(lat * 1e7),
    round(lon * 1e7),
    math.nan,
)

ack = master.recv_match(type="COMMAND_ACK", blocking=True, timeout=3)
print(ack)

Use the endpoint that reaches Cyclops in your deployment. With MAVProxy, that is the flight-controller path or a configured upstream endpoint like the example above.