Tips and tricks for troubleshooting and flying drones safely

Your drone may have some problems when you fly it regularly or if you have just started piloting a drone. This can be because of maintenance or accidents. So, we need to troubleshoot and fly our drone safely. In this article, we will look at a few common troubleshooting drone tips.

This is an excerpt from Building Smart Drones with ESP8266 and Arduino written by Syed Omar Faruk Towaha. 

1. My drone tries to flip or flip when I turn it on

This problem may occur for several reasons. Check if you calibrated your ESCs. Are your propellers balanced? Have you configured the radio properly? Are your ArduPilot's sensors working properly? Have you checked all the wire connection? Have you calibrated the drone frame? Have you added the wrong propellers to the wrong motors (for example, clockwise propellers to anticlockwise motors)? I hope you can solve the problem now.

2. My motors spin but the drone does not fly or take off

This happens because the motors are not giving enough thrust to take off the drone. From the parameter list of the Mission Planner, change THR_MAX . Make sure it is in between 800 and 1000. If THR_MAX is 800 and still the drone does not take off, change the parameter to above 800 and try flying again.

3. My drone moves in any direction

The drone moves in any direction even though the stick of the transmitter is cantered. To solve the problem, you must match the RC channel's 1 and 2 values to the PWM values displayed on the Mission Planner. If they are not the same, this error will happen. To match them, open your Mission Planner, connect it via telemetry, go to the Advanced Parameter List, and change HS1_TRIM and HS2_TRIM. With the roll and pitch stick cantered, the RC1 channel and RC2 channel should be the same as the values you wrote for the HS1_TRIM and HS2_TRIM parameters.

If the values are different, then calibrate your radio. The HS1 trim value must match the live stick cantered roll value, and the HS2 trim value must match the pitch stick cantered value. You must not use the radio trim for yaw. Make sure the center of gravity of the copter is dead center.

4. When I pitch or roll, the drone yaws

This can happen for several reasons. For the brushless AC motors, you need to swap any two of the three wires connected to the ESC. This will change the motor spinning direction. For the brushless DC motors, you need to check if the propellers are mounted properly because the brushless DC motors do not move in the wrong directions unless the connection is faulty. Also, check that the drone's booms are not twisted. Calibrating the compass and magnetometer will also help if there is no hardware problem.

5. It faces GPS lost communication

This happens because of a bad GPS signal. You can do one thing before launching the drone. You need to find a spot where the GPS signal is strong so that it can be set to return to home or return to launch if the radio communication is lost. Before flying the drone, you may disarm the drone for a couple of minutes in a strong GPS signal.

6. It shows radio system failed

To solve this issue, we can use the radio amplifier. Using the radio amplifier can increase the signal strength. You can have radio failure when there is a minor block in between the drone and the receiver.

7. My drone's battery life is too short

When a drone is not used, we should keep the battery stored at room temperature with low humidity. High temperature and moisture will cause the battery to damage the chemical elements inside the battery cells. This will result in a shorter battery life. For the LiPo battery, I would suggest using a balance charger.

8. Diagnosing drone problems using logs

For our ArduPilot, we used telemetry to communicate the drone to our Mission Planner. So, after the flight, we can analyze the telemetry logs. The telemetry logs are known as tlogs. There is Sik radio telemetry, Bluetooth telemetry, XBee, and so on. Before going any further, let's see where we can find the data files and how we can download them:

1. In the home screen, you will find the telemetry logs below the Flight Data panel. From there you can choose the graph type after loading the log.
2. When you load the logs, you will be redirected to a folder where the tlogs are situated. Click any of them to load. You can sort them by time so that you can be sure which data or log you need to analyze. You can also export your tlog data to a KML file for further analysis.

You can also see the 3D data of the flight path from the tlog files:

1. Open the Mission Planner's flight data screen. Click on the Telemetry Log tab and click on the button marked Tlog>KML or Graph. A new window will appear. Click on the Create KML + GPX button. A .kmz and .kml file will be created where the .tlog files are saved. In Google Earth, just drag and drop the .kmz file and you will see the 3D flight path.
2. You can see the graphs of the tlog files by clicking Graph Log on the screen after the Togl>KMs or Graph button has been clicked. From there you need to select the flight tlog and a Graph this screen will appear. Check the necessary data from the screen and you will see the graphs.

We have learned to diagnose drone issues through logs and have also learned to analyze graphs depending on data and troubleshooting flight problem. Get to know more about radio control calibration problems and before/after flight safety from this book Building Smart Drones with ESP8266 and Arduino.

Drones: Everything you ever wanted to know!