Gimbal

For those who are crazy about aerial photography, or high quality FPV videos, you might want to consider using camera gimbals. Camera gimbals could be driven by brushless motors or servos. The choice between brushless motor, or servo based gimbals ultimately depends on what you have and what you need. Although brushless gimbals are very popular right now I still think there is a place for some of the servo based gimbals. So we will discuss the pros and cons of each type of camera gimbals for quadcopters, and other multicopters.

What is a Camera Gimbal and How does Gimbal work?

When quadcopter is flying, in order to to maintain balance either automatically or manually, the motors changes speed to adjust roll/pitch/yaw angles. Therefore even with the best balanced aircraft, you will still see some level of shakiness in your video. By using a cemera gimbal, it compensates the change of roll/pitch angle, and leaves  the camera steady so you have perfect images.

Camera gimbals can remove some of the shakiness by stabilizing all three axes (Pan, Tilt, and Roll or sometimes just 2 axis) with the help of brushless motors or servos, and sophisticated sensors and micro controllers. You can freely move around with your camera and the Gimbal will keep it steady.

Also vibration from the motors could translate to the gimbal, if the copter shakes up and down that camera will shake up and down as well. When the shaking is in sync, it’s not as bad as they will cancel out. But when the shaking frequency is not the same (out of sync), it will result in terrible image, what we call “jello”.

Do I need a Camera Gimbal?

If you don’t care about video quality and it doesn’t bother you, you don’t need one.If you want one, your options are basically servo driven or brushless motor driven gimbals.

Servo Gimbals are generally cheaper, and lighter. Most flight controllers can handle servo gimbals so additional controller and sensor are not needed for this type of gimbals. However Brushess Motor gimbals give you better result, smoother image quality. I will try to explain further in the following article of the goods and bads of both types of gimbals.

Servo Gimbals

First impressions of the Servo based gimbals are, cheap, and light weight.

However they give amateur looking results, you can still see some jittering in the video due to overshooting movements. It’s a mechanical limitation of the servo. They are also slow to react because of the fundamental structure of a servo. More complex servo and Digital metal gear servos might be better, but then it gets expensive.

The light weight feature is very good for RC air-planes and quadcopters, also many flight controllers support servo gimbals, so you can just plug the servos directly to the FC, and don’t need to worry about additional controller board. Brushless gimbals usually require a separate control board, and sensor.

I personally like using servo gimbals for my FPV cameras where video quality is not essential. When I just want to be able to turn the camera horizontally and vertically using my radio transmitter, so I can look around in the air.

Brushless Camera Gimbals

Apart from being the opposite of the above, you cannot deny the video quality offered from a brushless gimbal is better. The reaction is fast, and the movement is very smooth.

However if you only mainly shoot photos then you can save some money and weight to use a servo gimbal.

Conclusion

Overall I would suggest that you go for a brushless motor gimbal if you plan to shoot aerial photography type of video, whenever you can. ‘Weight’ is one of the most important factors with multicopters, you can flight longer for every gram you save. Take a look at the experiment I did earlier about weight and flight time.

Both types of camera gimbal work, the question is which one do you need. I can see there is a decrease in the price of brushless motor gimbals, some can be as low as $60. If you ask me is a $120 gimbal better than than the $60 one? The answer is most likely to be “yes”. But is it twice better? Probably not.

No matter what gimbal you use, balance it before power on. It makes a HUGE difference.

Anyway, many people consider camera gimbal as a “luxury upgrade” than a “necessary upgrade”. In exchange of getting better quality recording video (hopefully), you will lose something in return. It doesn’t make flying easier, safer, or more fun, but adding extra weight to your aircraft, shortened flight time, and will cost you quite a bit of money. Not to mention in the case of fatal crash or fly away, you would lose more $$. So there are quite a few things to consider before clicking the “buy” button.

Naze32 vs CC3D

 

What are Naze32 and CC3D?

I wrote a very brief post on some of the popular flight controllers not long ago. In this post I will focus on comparing the differences between Naze32 and CC3D flight controllers, hopefully can help you to decide which you should get.

Naze32 and CC3D are both modern 32-bit Flight Controllers, compared to other 8-bit FC such as the KK2.1 or APM2. This gives them advantages in precision and computation speed. Both FC are also popular in acro flying especially with mini quadcopter FPV racing. CC3D has been around for years, and Naze32 came later.

In this comparison, I am referring Naze32 to the “Acro” version, not the “Full” version which has built-in compass and baro. There is also another FC in this class called “Flip32+”, it’s very similar to the Naze32 (allegedly a clone of Naze32) and we won’t go into detail about it.

Hardware Comparison: Naze32 vs CC3D

They are very similar to each other: both are 36x36mm in size and use 32-bit STM processor. But Naze32 uses a MPU6050 sensor chip (gyro + accelerometer) and CC3D uses the MPU6000. The MPU6050 is a better sensor in theory, but whether the firmware developer is taking advantage of that is another matter.

 

 Naze32 has 3 colours, black, white and red

PC Connection: The Naze32 has Micro USB and the CC3D has Mini USB.

As for component connection, the Naze32 uses standard servo lead pins, while the OpenPilot CC3D uses JST type plug. I guess the reason is to save space, but I find it truly not convenient.

 

 CC3D has 2 colours, black and white

The CC3D board has a USB port that is directly connected to the processor. Other boards like the Naze32 and Flip32 have an on-board USB to UART adapter which connect to the processor’s serial port instead. That means when you flash firmware like Cleanflight on the CC3D board, additional USB-Serial converter is required.

 

Software Comparison: OpenPilot GCS VS Baseflight & Cleanflight

So with the similarity in hardware, you will find software to be the complete opposite.

Naze32 and Baseflight

Naze32 uses Baseflight configurator. The firmware is originated from Multiwii, which has a lot of parameters you can play around with to fine tune the performance of your quadcopter.

Baseflight configurator is a Google Chrome App, the design is very simple and straight forward. Apart from the graphics interface, there is also a command line style interface “CLI”, where you can find all the setting variables.

 

CC3D and OpenPilot GCS

On the other hand, the CC3D was somewhat limited in terms of tuning, and since the appearance of Naze32 people was complaining about the lack of “locked in” feeling with this FC compared to the Naze32. After that the developers improved it, and offered users more freedom to fine tune their quadcopters especially for Acro flying.

The OpenPilot GCS is very well design GUI with user friendly interface. However I somehow find it a bit complicated especially for beginners.

 

Cleanflight

With the success of Naze32 and Baseflight, the firmware and configurator were forked and Cleanflight was born. It does not only support Naze32, but some other flight controller boards as well such as CC3D, Sparky and so on.

 

 



 

 

What’s even better is, you can have both firmwares OpenPilot and Cleanflight installed on the CC3D board if you want.

Currently, this firmware doesn’t support Hexacopter and Octocopter configuration on the CC3D.

You can find more information about Cleanflight and Baseflight here.

 

Which One Should I Get?

They are both good Flight controllers, it’s hard to decide. You might find people debating which is better in terms of performance. But I think each board has their own audience and they both get the job done. You probably can’t tell until you try both out.

I personally find the Naze32 is easier to plug in my radio and other components, because of the standard servo plug pins. Extra soldering might be required with the mini JST cables on the CC3D. Also I found the Baseflight / Cleanflight configurator is easier to use as well.

But price wise, CC3D is about 40% cheaper than the Naze32 currently. If you want to run Cleanflight, and don’t mind the JST connectors, CC3D might be a good option. It’s interesting to know that just over 6 months ago, the CC3D used to be priced at $65 for some reason.

 

Flash Cleanflight on CC3D

From the Cleanflight documentation, it seems there are two flashing modes, one, you can completely remove OpenPilot and install Cleanflight, two, you can run both firmware on the board. For more detail check out the Cleanflight documentation.

Do it in Cleanflight with USB UART Adapter

Connecting the CC3D flight controller with the USB to UART adapter: 5V, GND, TX and RX to the MainPort on the CC3D. Now follow the instructions here to flash the firmware just like how you do it with the Naze32.

After flashing your CC3D is now literally a Naze32, all the settings can be done through the Cleanflight configurator.

Do it in GCS without USB UART adapter

Aternatively, you can follow this video (Jan 2015) and this video (Feb 2015) to flash it without an usb/uart adapter. Basically you load up GCS, go to firmware, hit “HALT” to put the board in bootloader mode, download the Cleanflight FW, flash it. If you want to go BACK to OpenPilot from Cleanflight. Just load up GCS, go to Firmware, hit “Rescue” and follow the prompts. You’ll need to download a FW image of OpenPilot, and then load it back.

FPV Frequency

Radio Frequencies for FPV

As soon as you look deeper into FPV flying, you will realize not only there are many brands of equipment you can choose from, there are also a range of different FPV radio frequencies available. Usually people decide on what frequency they want to use before picking a brand/model of FPV system, since some of the brands specialize / only produce equipment for certain frequencies.

Usually these frequencies are available for FPV system equipment.

• 900 Mhz


• 1.2 ghz


• 1.3 ghz


• 2.4 ghz


• 5.8 ghz

Difference in FPV Frequency

Generally, you want to go lower in FPV frequency, because the lower the frequency band, the longer the waveform is produced. The longer the wavelength, the better it can get around or penetrate objects such as hills, buildings and trees (see penetration depth VS frequency), so the longer distance the signal can travel in our flying environment.

Unfortunately, not all frequency bands are legal, and there are restrictions on certain frequencies in some countries. Do find out about what frequencies are legal to use in the country you are planning to fly FPV, before buying the equipment. In this article, I will use the UK as an example.

900 MHz

Brilliant range, great penetration.

This would have been the most obvious choice for FPV, but the UK government start using this frequency band for mobile 3G network in 2009, so it’s no longer legal.

1.2 GHz

This band provides great range and good penetration ability. But again it’s illegal for use in the UK as it’s used by other sources.

1.3 GHz

Similar Good range and good penetration ability to the 1.2 GHz band. People in America use this frequency band for transmitting video/audio if they have a Amateur Television or ATV license from a ground based station. For the UK at the moment it is used for aerial work, so it’s again illegal in the UK.

2.4 Ghz

You can get a good range out of this frequency band, and it has a very good range to power ratio. The 2.4 GHz video equipment is very popular among FPV frequencies, and it’s the most commonly made equipment and generally is the cheaper of all the bands to buy.

However, the penetration ability is not very good compared to the previous frequency bands. Also since it’s the most popular band for many other equipment such as WiFi, Bluetooth, RC transmitter/receiver, you might get serious interference. So usually if you decide to go with this band for FPV, you need to choose a difference frequency for your RC transmitter, and telemetry (if you are using one) other than 2.4GHz.

5.8 GHz

Finally, the 5.8 GHz frequency band is growing in its popularity, and manufacturers are making it cheaper and more affordable. This band is useful because its off the 2.4GHz that most flyer’s will be on so that’s that problem solved. Another good thing is thecircular polarized antenna can be made very small, thanks to the high frequency. These antenna can solve problems on poor reception due to polarization and multi-path. Many FPV pilots have been using this system and it’s been proven practically that this a great frequency band for FPV.

Although it has got a decent range to power ratio, again due to the high frequency it has a very poor penetration property. Therefore flying is restricted within line of sight area mainly. It is most useful for multicopter pilots (quadcopter, tricopter, hexacopter and so on), which doesn’t fly very far away compared to air planes (within 500m to 1 km range?). And the video transmitter can be in close proximity to everything else with no obvious negative effects.

Legal FPV Frequency and Power Level In The UK

Not only are there certain frequencies that are legal for FPV flying but there are also constraints on the video transmission power levels as well. For more detail check out this PDF.

So we know we can only use 2.4Ghz and 5.8 Ghz frequency bands for FPV in the UK, we will have a look at these for their max legal transmission power level.

For 2.4Ghz, the max power is 10mW. For 5.8Ghz the max power allowed is 25mW. (information from here)

Conclusion – What Frequency Should We Use for FPV?

In the case of flying FPV legally in the UK, not fun at all. Most decent FPV equipment are baiscally illegal to run due to the transmission power restrictions. However if we are only talking about frequency, the most popular choice is using 2.4 GHz for Radio control and 5.8 GHz for FPV, for the reason of being legal and the cheapest option.

Some people have also suggested using the 35MHz for radio control, which gives us excellent range and faultless results for control, as the 35 MHz doesn’t affect the video signal at all. And use the 2.4 GHz for FPV, which keeps us all legal and have good video quality.

I have also seen people flying FPV with illegal frequency and transmission power level, A LOT, without getting caught. When you are flying in a remote site, I seriously doubt anyone would notice you are there using a illegal frequency band, unless you annoy someone by affecting their activity. Of course, you should always follow the law, and don’t do anything stupid.

There are also things to consider when choosing frequency for your FPV system due to the fact that harmonic frequencies can cause interference, for example 2.4GHz might interfere with 5.8GHz. But from experience it doesn’t seem to be too much of a problem for me and other people I know, so I won’t talked about this in this article.

RC Radio Signals

PWM, PPM, SBus, DSM2, DSMX, SUMD

 

When it comes to radio transmitter and receiver, acronyms are often mentioned: PWM, PPM, SBUS, DSMX and so on. These are the different radio communication protocols and technologies. In this post we will explore the differences of these radio signal types. We will also have a look at some of the technology, and see how it makes flying more reliable and safer.

PWM

This is the most common receiver output signal. In the old days when there were only RC fixed wings planes, the receivers were used to control the servos or ESC directly with standard PWM signal, one channel for each servo. Until today the same technology is still being used. Multirotors require at least 4 or 5 channels (sometimes even more) and you will see the same numbers of servo leads connected between the receiver and flight controller.

PWM radio receiver is the most common and usually the cheapest option.



PWM stands for pulse width modulation, the length of the pulse specifies the servo output or throttle position. The length of the signal pulse normally varies between 1000 & 2000µs (micro seconds), with 1000µs being the minimum & 2000µs the maximum.

PPM

PPM is also known as PPMSUM or CPPM. The advantage of PPM is that only one signal wire is needed for several channels (typically 8 channels max), instead of a number of individual wires. So you should only connect the ground, power and signal cable.



A PPM signal is basically a series of PWM signals sent one after another on the same wire, but the signal is modulated differently.

PPM is what they call “analog signal in time domain”, channels are sent one after another and not at the same time. Therefore tt’s not as accurate or jitter free as serial communications, but it’s more widely available and supported by many Flight controllers.

Check out this post for a more detail difference between PWM and PPM.

PCM

PCM stands for pulse code modulation, it’s a data types like PPM. However PCM signal is digital (ones and zeros) and the PPM signal is analogue, which is the length of time the signal is on. PCM has the potential of signal error detection even error correction, but this still depends on the product you buy.

PCM is more reliable and less susceptible to interference, but additional conversion is required so the equipment is more expensive in theory. But it looks like PPM is still the mainstream in RC radio at the moment.

Serial

Serial Receiver is a digital loss-less protocol that uses only 3 wires (signal, power, ground) for multiple channels. As the name suggests this type of receiver requires serial port on the flight controller. This includes SBUS, XBUS, MSP, IBUS, and SUMD.

SBUS (S.BUS) – Frsky, Futaba

SBUS is a type of serial communication protocols, shared by Futaba and FrSky, that supports up to 18 channels using only one signal cable.

SBUS is an inverted UART communication signal. Many flight controllers can read UART input, but cannot accept inverted one (such as the Naze32) and an inverted is required. But some FC such as Pixhawks has built-in dedicated signal inverter for this purpose.

XBUS – JR

XBUS is used by JR, which supports up to 14 channels in one signal wire. One of the advantages is the tiny time delay between each channel.

MSP (multiwii serial protocol)

Protocol that was created as part of the multiwii software. Basically it allows you to use MSP commands as the RC input and it supports 8 channels in one signal cable.

Flysky IBUS

IBUS is the new flysky serial protocol. It’s a two way communication: one port for servo data output and one port for sensors.

Graupner Hott SUMD

The Graupner SUMD is a serial protocol like Speksat and SBUS. The channels are encoded into one digital signal and there you have no latency. But we are talking ms of difference, I doubt anyone can tell the difference. Advantages of SUMD:

• VS SBUS – SUMD doesn’t require signal inverter.


• VS PPM – SUMD has better resolution and zero jitter while PPM has only 250 steps and always 4ms jitter.

Graupner SumH

SUMH is a legacy Graupner protocol. Graupner have issued a firmware updates for many recivers that lets them use SUMD instead.

Spektrum DSM2 and DSMX

DSM2 signal is more resistant to noise, interference and other transmitters transmitting on the same frequency. It also finds a backup frequency at start-up in case the primary frequency fails. This lower the chance of losing signal greatly, however if both channels becomes unusable you may still lose the connection.

DSMX was based on and improved from DSM2, which also uses the same econding scheme. The difference is the DSMX signal is able to switch to a new frequency channel in case of cut out within a couple of milliseconds, so in theory you wouldn’t even notice the glitch.

DSM2 is still a popular technology, if you are away from sources of radio interference (such as wifi, microwaves, and wireless security cameras), it should work just as well as DSMX. But DSMX is just more reliable.

Spektrum Satellite

A Spektrum Satellite is an additional antenna and receiver circuit that usually gets connected to the “main” receiver to improve link reliability by providing diversity reception.

Raspberry pi FPV

First, we connect the camera to the intended CSI interface (pictured above) and start the configuration tool of the Raspberry Pi.

pi @ raspberrypi ~ $ sudo Raspi-config

 

Further down the line "Enable Camera" should be visible. If simply press Enter, save, and the Raspberry Pi with "sudo reboot" Yes, restart the computer. If the line is missing, the system must be brought up to date with the following two commands:

pi @ raspberrypi ~ $ sudo apt-get update
pi @ raspberrypi ~ $ sudo apt-get upgrade

Take pictures

Shot in Jpeg format

pi @ raspberrypi ~ $ raspistill -o image.jpg

 

Shot in PNG format
The -e option you can create the file types jpg, bmp, gif and png.

pi @ raspberrypi ~ $ raspistill -o -e image.png png

 

Without receiving Preview

pi @ raspberrypi ~ $ raspistill -o -n image.jpg

 

Recording on left and right keys (Enter)
Is replaced by image image.jpg% 02d.jpg a new file in the format image01.jpg is created each left and right keys.

pi @ raspberrypi ~ $ raspistill -t 0 -k -o image.jpg

 

Delayed Up (3 seconds)

pi @ raspberrypi ~ $ raspistill -o -t image.jpg 3000

 

Shot in a lower resolution (640x480)

pi @ raspberrypi ~ $ raspistill -o -w 640 -h 480 image.jpg

 

Shot in a lower quality
The reduction of quality saves disk space. Valid values ​​are from 0 to 100 possible.

pi @ raspberrypi ~ $ raspistill -o image.jpg -q 20

 

Time-lapse recording
Use the following command to one hour (-t 3600000) every 5 seconds (-tl 5000) added a picture. The name% 04d is the file name for a four-digit numbering (eg image_0001.jpg).

pi @ raspberrypi ~ $ raspistill -o -t image_% 04d.jpg -tl 5000 3600000

 

The images created can be converted into an mp4 video file with the tool ffmpeg.

pi @ raspberrypi ~ $ ffmpeg -r 5 -qscale 4 -b -i 9600 IMG_% 04d.jpg zeitraffer.mp4

 

Record videos

5 second video in 1080p (1920 x 1080)
The option -t gives you the recording time in milliseconds. For an infinite recording (eg for a stream) simply set the value to 0.

pi @ raspberrypi ~ $ raspivid -o -t video.h264 50000

 

5 second video in 720p (1280 x 720)

pi @ raspberrypi ~ $ raspivid -o video.h264 -t -w 1280 -h 720 50000

 

With individual video bitrate (3.5MBits / s)

pi @ raspberrypi ~ $ raspivid -o video.h264 -t -b 50000 3500000

 

With individual video frame rate (10 frames / second)

pi @ raspberrypi ~ $ raspivid -o video.h264 -t -f 50000 10

 

Send video stream to stdout

pi @ raspberrypi ~ $ 50000 raspivid -t -o -

 

Convert videos

H264 mp4 by

pi @ raspberrypi ~ $ sudo apt-get install gpac
pi @ raspberrypi ~ $ MP4Box -add -fps 30 video.h264 video.mp4

 

LED on / off

1. Method
Add the following line to the file "/boot/config.txt" to and do a reboot. Unfortunately, it can happen that the settings are lost after a reboot.This is related to Kompatibilitätsroblemen some SD cards. If this is the case, edit the file to a different Linux box and use the second method.

disable_camera_led = 1

2. Method
Once deactivated by the above method, the LED on the GPIO 5 can be controlled.

pi @ raspberrypi ~ $ sudo echo "5"> / sys / class / gpio / export
pi @ raspberrypi ~ $ echo "out"> / sys / class / gpio / gpio5 / direction
pi @ raspberrypi ~ $ echo "1"> / sys / class / gpio / gpio5 / value

 

Stream on other Raspberry Pi computer or

Preparing the server
Use the tool Netcat can send the stream generated by raspivid directly to another computer or Raspberry Pi. Therefore one must only know of the receiver (client) IP address. This one shows under Unix with ifconfig and Windows computers with ipconfig.
Example In the following the stream to another Raspberry Pi with the IP address 192.168.178.20 is sent to port 5001:

pi @ raspberrypi ~ $ sudo apt-get install netcat
pi @ raspberrypi ~ $ raspivid -t 0 -o - | nc 192.168.178.20 5001

 

Preparing the Client - Linux
The Raspberry Pi / Linux client of the video player MPlayer in addition to netcat installed later to the stream directly displayed on the graphical interface.

pi @ raspberrypi ~ $ sudo apt-get install mplayer netcat
pi @ nc -l -p raspberrypi ~ $ 5001 | mplayer -fps 31 -cache 1024 -

 

Preparation of the client - Windows
If not already have the tools Netcat and MPlayer be installed.
The stream is started with the following command in the command prompt.

[Path to nc.exe] nc.exe -L -p 5001 | [path to mplayer.exe] mplayer.exe -fps 31 -cache 1024 -

 

Flytime calculator

Raspberry pi Spectrum Analyzer

[su_document url="http://www.larsleonhardt.com/wp-content/uploads/2015/04/freq-show-raspberry-pi-rtl-sdr-scanner.pdf" width="520" height="560"]

OSD Programming with Arduino

 



One great feature that we should add to FPV would be flight data on the screen display (OSD). By programming the MinimOSD, not only you get more accurate data on the screen, you can also select, edit what kind of data you want to have on the screen. The Crius AIOP board is supposed to work well with the MinimOSD, so I gave it a try.

I realized that you need a FTDI cable to do the programming, but if you happen to have an Arduino Uno like I do, then it’s your lucky day because you can easily turn your Arduino in to a FTDI programmer. I will show you how after the break. You can buy an Arduino from Newark.

Connecting Arduino with MinimOSD

How does it work?

A bit of technical background, skip if you like.

The Arduino UNO has an FTDI USB-TTL chip on it to communicate between a PC and the ATMEGA chip on the board. Because all of the necessary pins on the FTDI chip are connected to various pins on the edge of the board, we can just connect the MinimOSD up to the right pins and away we go! No need to spend extra money on the FTDI cable!

Let’s connect them

The connection is very simple. But first of all, if you don’t have an Arduino Uno but other Arduino boards, you need to make sure it has a FTDI chip otherwise I am afraid you are out of luck.

Connect your arduino to the computer, remember what COM port it has been assigned. Then unplug the Arduino from your PC.

Remove the ATMEGA chip from the socket. If yours is soldered directly to the board then you may still be able to continue, but you will also program the ATMEGA chip at the same time which you probably don’t want to do. This way we are just passing the data through the board to the output pins. Removing the chip means you won’t accidentally bugger up the ATMEGA chip.

Connect your MinimOSD to the Arduino board as follows:



Note that BLK on the MinimOSD is not connected to anything. Also note that TX is connected to TX, RX to RX – you don’t need to reverse them!

Connect the Arduino to your PC again. Your PC should recognize the device as usual and assign it the COM port we noted down earlier.

You should now be able to program the MinimOSD. However the way of programming it depends on the firmware, read on to see how.

Different Firmware for MinimOSD

Here comes the confusing part. There are some many different firmware suggested by people, I had no idea which one to use. After a lot of research, it turned out that we should flash the MinimOSD with different firmware, to work with different flight controller firmware. These firmwares are both open source, so it’s free to get them.

For MegaPirateNG, you should be using ArduCam-OSD, or MinimOSD-Extra. This firmware provides a very handy GUI tool, which allows you to flash firmware, and program the MinimOSD. All you need to do is to select the COM Port, browse to the firmware file, and click “upload firmware”.

For Multiwii, you should be using Rush-OSD. With this firmware you need to use the Arduino IDE to open the firmware files as a sketch, and upload them like you do with a normal Arduino.

It works great with this wiring diagram when using MegaPirateNG. But it just WON’T work with Multiwii for some reason. No matter which Serial port I plug the MinimOSD to, the ST LED didn’t light up, I get no image from the OSD. Although it’s working fine when testing with the Rush-OSD Gui and I can see the ST LED blinking. I think the Crius AIO Board is not talking to the MinimOSD, because the MinimOSD only accept certain data format (maybe telemetry data), and I couldn’t see any settings in the Multiwii config.h file either. After a couple of hours of trying and researching, I decided to leave it there. I don’t need it right now anyway.



I think that’s it, if I made any mistakes in explaining please let me know because I have only looked into this in the last few hours.

Thoughts about these open source OSD projects

I am sure the developers must have put much efforts and time into these projects, they do this not for money but for the convenience of others, and we are all very grateful.

However It’s not very straightforward to work these things out, because they are not well documented, and what is documented is not user friendly, at all. The “instructions are all over the place, you need to read through some 100-page long forum threads. Most of the time you need to guess, and do lots of trial and errors. After hours of trying only find out it’s not working. Very frustrating.

That is the problem with open source stuff, and sometimes it’s wiser to pay a little bit more and save the troubles.