according to my understanding the Camera Tilt and record start/stop function is directly managed by the Wi-Fi frontend firmware and the Flight Controller FW is not involved in this.
For this reason, camera control is not available on the C-FLY logs.
The basic Drone architecture should be something like this (bottom camera is certainly different, but general architecture should be ok):
Serial5 embeds the RC control commands through a Mavlink interface.
QUESTION: does anyone know how to retrieve C-FLY listener logs from an iPhone? Is there any File Manager that could let me browse trough the iPhone filesystem?
I believe the bottom camera is not an actual camera, it’s a optical flow sensor which in effect is a video camera but it’s signal is not intended for display and there should be some sort of processor that takes this imagery in and outputs movement increments that feed into the flight controller as deviations from a specific position. Since there is no GPS involved it can only provide deviations, not absolute values for position, so the FC takes this info and corrects to the supposedly previous position. The precision of this mechanism is actually quite good, even with these low-end sensors and slow boards. As I understood this kind of position sensors, the frequency of updates as well as sensitivity of the optical sensor are key in how effective this system is. Obviously it’s best used indoors where there’s no GPS signal, but as I recall DJI uses a sort of “sensor fusion” to get GPS position data and then refines it with the optical flow giving them that rock solid positioning they boast.
Maybe I’m mistaken so I’ll gladly welcome any corrections.
The bottom camera IS a low resolution video camera plus the processor to compute horizontal deviations for the Flight Controller.
That’s why I’ve depicted it as part of the Wi-Fi/Camera sub-system in my block diagram above.
You can even display it on the C-FLY app (at least on Android, not sure about iPhone), take pictures from it and I found it very useful to pinpoint the landing pad when flying BVLOS!
I know it’s a video camera and you can see its live feed, just that you’ve shown it as part of the main camera which I think could be misunderstood as being dedicated for the video part when it’s actually intended to be used for positioning and landing, as you mentioned.
My block diagram reflects the real physical connection of the bottom camera, you are free to improve it if you believe to have a better understanding of the drone architecture…
Hi Daniele. I was reading all of this post hoping to find an answer to my wish; I don’t want (presently) modify my EX4 hardware to add a USB connector but I would like to download pictures and videos stored into the SD (TF) plugged into. I saw that the Drone should be reachable by an FTP request to the IP 172.50.10.1 but I do not know the answers to give when it requires a Username and a Password to establish the connection. Can you (or anyone on this site) help me?
Thanks in advance
Not my intention to contradict on your diagram which seems to be in line with how I think this drone is wired as well, my comment was just about the optical flow sensor which you’ve shown as being solely connected to the camera/gimbal assembly and then to the wifi module, which is correct since the video feed from the sensor camera is viewable on the app, but its main purpose I think is to provide the optical flow information to the flight controller so I would add a line from this sensor to the FC, not removing the one to the camera/gimbal assembly though since that is a valid existing setup but to complement it.
I don’t think the optical flow processing is done on the phone, then the corrections are sent back to the FC via wifi. This would be very slow, cumbersome and dangerous.
But you can read on your phone all the images stored on the SD Card. The app has this option to preview and download locally both images and videos. On the right hand of the screen there are 3 icons for taking stills, starting/stopping video and the bottom one is for opening the media library manager. Here you can see what’s stored on your phone and what media is on the drone. It’s not very user friendly and the download, particularly for large video files, sometimes errors out but it is functional once you get used with it.
My understanding from the literature is that the EX4 “Pro” (3km) version is referencing an improvement in image transmission distance, not actual control distance (note how the specs always say “3km image transmission”). This suggests the upgrade is only on the drone and not on the control transmitter. Can anyone verify this? Also, can anyone who has the “Pro” version in hand identify markings on the drone and/or box that differentiate the Pro version from the standard (“1km”) version? Thanks!
Thank you Denis for your reply. I was confused about the third icon on the right side because it’s named “Camera” so I thought it was referred to the live imagine on the camera and it seems to me a stupid feature. Instead I tried now your suggestion and…ok I see the list of pictures and videos stored into the SD but…yes, the download is very long but it works. The problem is…to know WHERE the download is stored. At the end I searched the downloaded file everywhere into my phone and…I do not find it. Could you tell me something more?
Thank you TT300. I found them; downloading the videos the names have been changed with a prefix that sounds like 1080p so I didn’t find them until now.
Ok, all is right.
So far I haven’t found anyone who has an EX4 “Pro” (“3 Km”) model to confirm what sort of range they’re actually seeing in terms of control and video, vs. the “standard” EX4.
My log in post 155 gives some other details in the top line.
I have not tested the range more than 50m as it keeps running away and crashing. I may try driving away from it to test the range with it on the ground but it will be hard to keep it unobstructed.
I would like to know what has been changed to get the claimed extra range - controller, quad or both incase I have to change a pcb to stop the run aways.
We haven’t really talked about the batteries for this unit much. Obviously they are 3S, and the label claims the max voltage is 13.05. Indeed QGC reports about 13.05 at full charge, so these are apparently LIHV batteries. This introduces a possible problem if counterfeit packs containing ordinary lipos start to appear, or if someone tries to replace the packs’ internal LIHV batteries with ordinary lipos (perhaps because of counterfeit batteries that claimed to be LIHV but actually weren’t). In all of these cases, depending on how the included battery charger works, the possibility of significant overcharge and damage would exist.
Has anyone cracked open a pack and determined the pinouts for the connector, batteries, and any internal circuitry? Any photos of the pack internals? Thanks very much!
Again I have to point to the FB groups, there are some folks who did just that, some because their packs swell so bad the case just burst open. I recall one guy who actually made some adjustments to allow a regular 3S LiPo balance charger to charge the packs. The control board on the pack seems to have indications about each cell’s pin so in theory it should be easy to adapt it to a regular charger for 3S.
This post might help:
You might need to join the group to see it though.
