16

A serial signal is composed of a series of High and Low electrical signals sent down a wire. In the standard serial protocol, a high signal is 0 and low is 1. In an inverted signal this is reversed so that a high is 1 and low is 0. You might think it makes more sense that low should always be 0 and high be 1 but electronics engineers decided that standard ...


11

Yes, you actually can! There are a couple of options for the Betaflight firmware which are mostly plug and play. OpenTX Lua Scripts Radios running OpenTX can use scripts written in Lua to control these parameters with the radio's scroll wheel and buttons. Please see @PaulKendall's answer for an explanation of how this method works. Betaflight OSD If you ...


10

This is a setting that is needed for RPM sensing and RPM filtering. An ESC can not sense the RPM of your motors directly, but can sense how often the magnets in the motor bell pass by the coils in its stator (this is called eRPM), and will report that number to the flight controller if you've got bidirectional DSHOT enabled. If your motor bell has x magnets (...


10

There are a few differences: Firstly, the F7 chip used in F7 flight controllers operates at a much higher frequency, so can handle more operations per second. This is useful when you want to start adding lots of dynamic filters, for example RPM filtering, alongside features such as antigravity. Whilst an F4 can handle almost anything you will want to ...


10

You might be able to write custom flight control software for a multi-copter that would simulate this. You might get close just by radically limiting the pitch and roll rates and being gentle on the throttle. In either case it wouldn't be intrinsic to the design. If you want smooth, soaring flight, you'd be best to build a fixed wing model with a fairly ...


9

(Edit: The original version of this question asked about "drones" in general. This answer was based on the question pre-edit, hence the clarification of drones vs. quadcopters.) First, a word of clarification. A drone is just any unmanned aircraft. The specific type of drone you described in your first paragraph is called a quadcopter. Now, if you ...


6

There are three ways you should know to enter DFU mode. The first, as mentioned before, is to push down the bootloader button and power on your board. The second method is to be used on boards that don’t have a bootloader button (which is increasingly rare). You will need to bridge two bootloader pads on your flight controller to enter DFU mode. Check the ...


6

DShot is a protocol that flight controllers use for communicating with ESCs. It stands for 'Digital Shot'. It is a new digital communication protocol developed by Flyduino in collaboration with Betaflight as an alternative to Oneshot and Multishot. Oneshot and Multishot (and standard PWM) all use analogue signals. The length of an electrical pulse ...


6

Airmode and idle up both seek to increase a control authority and stability during ultra-low throttle moves. In normal flight, when the pilot commands the multirotor to pitch or roll (cyclic), the flight controller responds by increasing thrust on one side of the craft and decreasing thrust on the other side by the same amount proportional to the cyclic ...


6

There is actually no such thing as a 6-axis gyro; the correct term for this is "IMU", which stands for "Inertial Measurement Unit". An IMU is a device that combines several inertial sensors that measure the craft's orientation and position in space. The 6-axis IMU is a composite sensor, which contains two different types of 3-axis sensors on one chip. ...


6

TL;DR: Probably, but you'd likely be spending a lot of time locating a programming interface on the flight controller board and custom-compiling or custom-writing firmware to work on the special board configuration. Some more expensive toy-grade drones may have accompanying smartphone apps that allow you to change some flight parameters, but very few of ...


5

Is the shunt resistor usually mounted high-side (i.e. at the positive battery terminal), or low-side (at the negative terminal), and why? Does it matter? There should be no significant difference to the measurement if the shunt resistor is on the high or low side. As the resistor is in series the absolute voltage across, and current through, the resistor ...


5

You can always run an older version of betaflight. Also, if you have older F3 controllers you may also like to like to look at https://github.com/spatzengr/betaflight/releases which are maintained by UAV Tech. I have used these on some older F3 boards and it breathes new life into these old boards.


5

Reprogramming toy-drone flight controllers which are based on readily recognizable microcontrollers is definitely "a thing", heavily benefiting from a few open source projects, one of the most popular being "Silverware" which has now become a whole family of repositories on github and years-long history of threads in places like rcgroups. ...


5

Beta flight has helicopter modes ("Heli 120", "Heli 90", etc. depending on your swashplate layout), as does pretty much every other programmable flight controller software. The outputs from the flight controller are the inputs for the ESCs, which have the same signal protocol as servos. The exception are the flight controllers with ...


4

@Kralc's answer is correct. However, besides device redundancy such setup is also used to achieve measurement redundancy. When the two gyros are mounted rotated (usually 90°) to each other, the flight controller is able to cancel out (to some extent) the effect of a noisy axis on one of the IMU's. In Cleanflight/Betaflight/Emuflight when dual gyro mode is ...


4

A major advantage is redundancy, so that the aircraft can continue flying if one fails. It is also common to see multiple GNSS (e.g. GPS) receivers, and sometimes even a redundant flight controller. Of course, the problem with only two is that the software can't necessarily tell which of them has failed; 'at least three' is common for high resilience ...


4

The rpm filters in betaflightwill be off the correct frequency by about 14%, and the rpm reported in the motors tab will be incorrect also. When the rpm notch filter centres are not exactly at the correct frequency, they won’t work as well, leading to increased noise in the motor signal, which may cause hot motors and limited thrust at high throttle.


4

In digital electronics, a signal is sent as a series of ones and zeros. In simple serial implementations, these are represented by zero volts and another voltage, typically 3.3V or 5V depending on the voltage of the system. Some systems use the higher voltage as the one and zero volts as the zero, but some are the other way around - hence, 'inverted', and a ...


4

After making sure that you have the RX_Loss beeper disabled, the next port of call would be to check your DShot config. It may not be the beeper that is making the noise - there is a DShot beacon configuration that allows you to set your ESCs to beep in the case of RX_Loss - Id recommend you make sure you have that setting correct. Edit: from your Diff ...


4

The short answer is that F7 is faster than F4, mainly because the F7 can execute two instructions simultaneously. At 216 MHz clockspeed, the STM32F722RE series you asked about has more than double the frequency of the STM32F411 series. What might matter the most apart from the speed when it comes to flight controllers is UARTs; the STM32F411 has 3 of them, ...


4

OpenTX LUA Scripts Also available if you have an OpenTX radio and a smartport telemetry capable receiver are the Betaflight LUA script available from https://github.com/betaflight/betaflight-tx-lua-scripts/releases These scripts allow you to change PIDs, Rates, Anti-gravity, D-Term Set point, Filters, PWM Settings, ESC protocol, Looptime, RX Settings and VTX ...


4

A three-axis gyro measures the speed of rotation in three-axis - pitch, roll, and yaw. A six-axis gyro is a slight misnomer, as it is a three-axis gyro with a three-axis accelerometer, which measures acceleration in three axes (x, y, and z). As it can measure the acceleration from gravity, these sensors can be used to determine which way is down relative to ...


4

You can do this with a configuration known as a 'repeater'; there are a number of examples of people using this to convert their favourite controller's RC system to that of a specific aircraft, but you could do the same with a single mode: FrSky to Dragonlink Repeater 2.4ghz to EZUHF repeater I'm not aware of an open-source implementation or Arduino ...


4

If you must use dshot then try this library https://github.com/gueei/DShot-Arduino However, for just playing around, it would be much easier to use PWM protocol and the servo library for Arduino. Most ESC's are backwards compatible so I recommend trying using PWM first and if you must, use DSHOT.


3

I think your best bet would be Ardupilot. The communication protocol it uses, called MavLink, is documented and easy to use. Connect to the UART with an Arduino and you will have full control over the UAV. There is even an Arduino library and a bunch of examples, like this forum post, of people doing exactly what you are looking to do. I did this once ...


3

Your description of the dramatic voltage drop (from 5V to 0.5V) upon the connection between the flight controller (FC) and 4-in-1 ESC makes me think that the issue you're seeing is most likely due to a short or low resistance path to ground. There are other possible failure modes that could cause this, but a ground fault sounds most probable here. Why? When ...


3

Reinforcement Learning can be used for UAV control. This video details a method to use RL for quadcopters. In summary, you program a model of your UAV that effectively simulates your drone. You then create a policy and value neural network to control your drone and train it using your simulation. I'm pretty sure similar methods are used in zipline's ...


3

The premise of your question is based on fairly limited observation of aviation. First there are many fixed wing "drones". They just haven't been as prevalent in the consumer market as in the segments of the hobby market that grew out of the longstanding R/C aircraft hobby, and in the professional market. Next, in terms of rotary wing flight, it's ...


2

Without knowing more specifics about the board(s) you're asking about, it's more than likely that the filtered power pads on your flight controllers are just the normal output from the 5v voltage regulator on the board which has a capacitor between the voltage regulator output and ground. Because the 5v regulator's output is shared by all kinds of devices ...


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