This post is about how i put a GoPro 4 Black on a Emax Tinyhawk 2 drone.
Before we start let me tell you this is not a great idea since even you strip the GoPro Hero 4 Black and bring it down to 23gr with the buttons and cables it is still too heavy for the Tinyhawk 2. Does it fly? Hell yea! But Im not sure how long the tiny ESC's can take the abuse. So if you are curious like me to see if it works and have a Tinyhawk 2 that you will not be upset making it useless in the second flight, than it is a go for you. Othervise it might not worth the risk. Also you will be able fly gopro with only 2s batteries. 1s batteries don't have the juice to power both the quad and the go pro! And even with a 2s battery, flight time is arround 2 minutes max (2s 300mah HV).
update: I have flown arroud 10 packs with little crashes no problems yet.
For a more proper gopro on a mini drone setup dont hassitate to visit the Naked Cinewhoop facebook group which you can find all the info about using GoPro 5/6/7/8 with ReelSteady software and having smoother results. All this info is available for GoPro 5 and above at the facebook group I mentioned above shared by many talented curious people. Im just addapting shared information to my GoPro 4 Black and adding on it where necessary.
For the lazies; just 3d print the supplied go pro / analog camera holder below, solder the right cables, strip down a GoPro 4 Black and put them all back together and fly it with a 2s battery.
For others; shell we start? Ok.
1- Striping Down A Gopro 4
There are tons of videos online. here is one,
What we need is the mainboard, lens and the image sensor as you can guess. We will not be needing any ribbon cables since we will attach our own switches.
Don't forget to bind the GoPro to your phone before tearing down your GoPro. Since there will be no screen and it will be not possible to pair it later once it is ripped apart.
By the way Im using a Hero 4 Black not because there is something secretly special about it, Im just using what I readily have :D
2- Wiring On The GoPro Mainboard I used mostly the test points in the mainboard to make the right connections and the buttons. On the GoPro mainboard I used ground, positive, shuter, Power On/Off, Wifi and Power Sense pins. There are a lot of info about this pins on GoPro 5/6/7/8 but I couldnt find much info on GoPro 4 Black, so here it is.
With this connection setup I was able to autopower the GoPro when Tinyhawk 2 is connected to the battery. I used 0.1mm enamelled copper wire for button connections and Micro JST ZH 1.5mm 3Pin connectors for the main connection to the Tinyhawk 2. So ; 1- connect power sense pin to power pin (to make work even without the battery) 2- connect on/off pin to ground pin (so gopro power ups as soon as you plugin the battery to drone)
3- connect a ground pin to both tacticle buttons as shown
4- connect shutter pin to one of the button's free pin as shown
5- connect shutter pin to JST yellow wire (this shutter pin is the same with previous one. By connecting this way we are having record button on go pro and a signal wire that we can use to trigger recording through flight controller)
6- connect wifi pin the other button as shown. (now we can enable wifi with that button)
7- Connect power pin to JST plug's red wire (this will be our main power cable for the go pro)
8- connect the top ground ring to the JSY plug's black cable (this will be our main ground for the power coming from the flight controller)
I know it looks messy with the blue tag (actually pink) and the exposed wires but dont worry, after applying the hot glue and liquid tape it will just look... worse! :D
I placed 2 tacticle buttons. One for start/stop recording, other is for wifi since GoPro Hero 4 Black does not automaticaly turn the wifi on. (Or i couldnt find the setting I dont know :/ ) Wifi is important if you want to live preview or change the setting of gopro later. I put a small peace of gaffers tape under the buttons to avoid contact with the mainboard. Also as you can see below, I am a big fan of liquid type, I used it to cover the enamelled copper wires since they are very fragile.
I also added an extra cable for the Shutter alongside with the power and ground cable since I will be using same GoPro on bigger setups and i want to be able to start stop recording through my radio controller (if the gopro lasts that long of course.)
3- Wiring On The Tinyhawk
I first tried the 3v soldering point for powering the go pro but it was not enough. So the free 5v soldering point was a good choice to go with. And for the ground wire I used the one that is shown in the picture. For the radio controlled shuter button i was planning to use the led soldering point but i couldn't find the corresponding target pin name in betaflight to make it work, so i left it alone. I used Micro JST ZH 1.5mm 3Pin connector here again to be able to fly the Tinyhawk without the gopro if I want to.
4-Asssambling I modelled and 3d printed a gopro holder which is basically a modified version of, Herr Wild's work (Insta360Go Holder) on Thingyverse. I added hot glue on the 3d print to make the gopro stay in its housing and on the corners of gopro's mainboard to make it a little bit more durable for the crashes.
Here is the 3D Model if you want to download and print it yourself. I used PP filament and it seems it has a great durability with good elasticity. Just put packaging tape to the building plate of your printer if you are having problems with this material.
5-Final Words It works. Barely, but it works. The total weight of the quad increased from 31gr to 56gr (without the battery) with this setup. And it became too back heavy which means not only the extra weight but also the lack of ballance is effecting the motors which probably lessens the life of the quad. But I will continue flying like this until my BetaFPV 85X comes :D
By the way I am using a free app called "Myk" on my iphone to connect my gopro on Tinyhawk. It seems to be quicker to connect than GoPro's own app. Here is a sample video from the GoPro'ed Tinyhawk.