Assistance with GPS Integration of Drones for Extended Flights

[Kitty12]

Hello Everyone ,

I’m currently working on a drone project focused on achieving long-range autonomous flights using GPS integration, and I’ve run into a few challenges. I’m using a Pixhawk flight controller with a Here2 GPS, and the goal is to establish a reliable GPS connection for precise waypoint navigation over extended distances (around 5 km or more).

I’ve already set up the basic GPS functionality and have successfully done short-range test flights (up to 1 km), but I’ve noticed that the GPS signal weakens as I increase the flight range, sometimes causing momentary losses in signal, which obviously isn’t ideal for long-distance autonomous missions.

Here are a few questions I could really use some help with:

1. Improving GPS Signal Strength : Are there any hardware adjustments or GPS module upgrades I can make to improve signal strength and reliability over longer distances?
2. Alternative Solutions : Should I consider adding RTK (Real-Time Kinematic) to improve accuracy and reduce signal issues? If so, any recommendations on compatible RTK modules?
3. Failsafe Settings : What are the best failsafe configurations for long-range flights to ensure the drone returns home safely if the GPS signal is lost or if communication with the ground station is interrupted?

Please help me. I need information on Indoor Autonomous Flying

I’m doing a college project and I can only work indoors. I’m getting ‘GPS: No Fix’ on the Mission Planner. I watched the course “Indoor Flying for GPS-less Flight” but it means I need to buy a new device. Will the Pi camera which came with the kit not do? For now, I just want the motors to spin with the Python code. Please provide me with any information you have. I would greatly appreciate any help. Thank you.

Any tips, recommendations, or experiences you can share would be greatly appreciated! I’d love to hear about similar projects or how you overcame similar challenges with your snowflake drones.

Thank you in advance!

[jax200]

Of course what you are asking is how you can improve signal strength to the GCS. The drone itself more than likely is getting a strong GPS signal for its mission.

Any radio signal will weaken with distance. That is why Caleb introduced drone control via cellular networks.
https://dojofordrones.com/4g-drone/

RTK helps with local operations that require more precision, not long distance control that requires greater signal strength. You would want to look at signal boosters or directional antennas instead. However, you might be stepping on regulations as governed, for example, by the US FCC.

You can set failsafe for various triggers.
Here are some common ones:

1. Radio Failsafe : This activates when the drone loses connection with the remote controller. The drone can be programmed to either hover, land, or return to home (RTH) when this happens
   (https://ardupilot.org/copter/docs/failsafe-landing-page.html).
2. Battery Failsafe : This triggers when the drone’s battery level drops below a certain threshold. The drone can be set to return to home or land immediately to prevent a crash due to power loss
   (https://ardupilot.org/copter/docs/failsafe-landing-page.html).
3. GPS Failsafe : If the drone loses GPS signal, it can switch to a mode like Dead Reckoning, where it continues to fly based on its last known position until the signal is regained
   (https://ardupilot.org/plane/docs/apms-failsafe-function.html).
4. Ground Control Station (GCS) Failsafe : This occurs when the drone loses communication with the ground control station. Similar to radio failsafe, the drone can be programmed to return to home or land
   (https://ardupilot.org/copter/docs/failsafe-landing-page.html).
5. EKF Failsafe : This involves the drone’s Extended Kalman Filter (EKF) system, which monitors the drone’s state estimation. If the EKF detects significant errors, it can trigger a failsafe response
   (https://ardupilot.org/copter/docs/failsafe-landing-page.html).
6. Vibration Failsafe : If excessive vibrations are detected, which could indicate a mechanical issue, the drone can be programmed to land immediately
   (https://ardupilot.org/copter/docs/failsafe-landing-page.html).
7. Parachute Deployment : In case of a critical failure, some drones are equipped with parachutes that can be deployed to safely bring the drone down
   (https://ardupilot.org/copter/docs/failsafe-landing-page.html).
8. Crash Detection : Some drones have sensors to detect a crash and can trigger a failsafe response to minimize damage
   (https://ardupilot.org/copter/docs/failsafe-landing-page.html).

However, it should be underscored for various reasons this project is a bad idea:

1. In most jurisdictions it is simply illegal to fly beyond the visual line of sight (BVLOS) without a waiver.
2. Regardless of regulations, it makes no sense to send an aircraft off on a blind mission, without any means of avoiding obstacles or situational awareness.
3. Your drone might impact a person/animal, another aircraft, an electrical wire, or start a wildfire. You will be responsible for the liability and criminal ramifications.

[nimbus]

1. GPS module is probably accurate enough (its about number of satellites connected, rather than a super expensive gps module)
2. That’s why RTK is unnecessary for what you are describing, which has to do with signal strength. DJI drones (like Mavic 2, Mini 4, etc.) are in theory rated for close to 10km signal range; however, this depends entirely on interference between RC controller and the drone- so you need to be in like a flat plains or high on a mountain to achieve anywhere near this distance even in theory.
3. In practice, you have to deal with the regulatory issue of BVLOS. If you are flying in a remote area and get a waiver, then you want a combo and redundancy of failsafes- such as 4G internet connection, and probably some very powerful control station. Auto return to home at low battery, RTH if signal is lost with RC controller, etc.