Intro: Hacking Heli Max Camera
This is my first instructable, instructions listed below are of my findings measuring control wires to the camera unit. In the future I hope to add to this on how to use with an Arduino or similar micro computer.
So I bought a Heli Max 1si because it had a camera and was at a decent price ($139.00). Wanted to try a quad copter for awhile now and finally made the dive into it. It was fun to fly, kinda frustrating at times but does well outside on calm days. The camera is capable of both video and still pictures.
But, I like to experiment ... what fun is there in buying something if it just goes about doing its only manufacturer intended purpose!
There are all kinds of video on You Tube for this thing if you want to check out video and still picture quality so I will stick to the point and post pictures as they relate to this. Just type in "1si quadcopter" into any search site and watch till your heart is content.
Step 1: The HMXZ0001 V-CAM Gets My Curiosity.
This camera is small and buying an extra like I did on Amazon to play around with was about $30. It is available from other sources too at varying prices, shopping around is a good idea. Part number is HMXZ0001 so type that into a search engine and see how cheap it goes for.
Camera has a built in micro sd card slot that stores the pictures, some websites state it can handle up to a 32 gig card, tested with an 8 gig card so far and it worked well. The sd card is the only way to store and retrieve pictures and videos. Original purchase of the 1si quad copter included a 2 gig sd card. Buying the extra camera unit did not include a sd card with it.
Camera head also swivels, will swivel about 45 degrees as shown in photos.
Camera Memory: Uses Micro SD Card
Camera Size: 40mm x 20mm x 8mm
Codec Video: Motion JPED, 1280 x 720, 30fps, file extension .avi
Codec Audio: PCM S16 LE, mono
Still Image capture: 1280 x 720, 96 dpi, file extension.jpg
Camera does well outside in bright daylight. Inside pictures will require a lot of light. Cant expect too much from such a tiny camera for around $30 USD. But it does do 720p HD! Maybe I will have to test out with an infrared light source in the near future for night time use.
Camera has 4 wires attached to it that plug into the quad copter so this cant be too difficult. The RC transmitter has 2 buttons, 1 for still pictures and another for video.
To activate still picture mode you hit camera button once to activate camera mode, hit it again it takes a picture. Same for video, took 2 button presses to take a video, 1 to activate and 1 more to start capture, and it takes 1 more to stop video, once your into video or still mode it just requires 1 button push to capture another still or video.
Step 2: Out Comes the Oscilloscope.
Started testing on the quad itself with a fully charged battery, 3.7v 350mah lipo.
Red wire measured 4.1vdc. (fully charged battery voltage).
Black wire was ground.
Yellow and Green wires were both at ground before pushing any buttons.
As you can see from the scope trace (set to 1volt dc per division and 1 second per division) when I pressed the camera button on the transmitter the receiver board on the quad sent a 2.8 volt 1 second pulse on the yellow wire as measured from ground. Scope trace picture shows me pressing button twice about 4 seconds apart, totally random time between button presses. Green video wire measured the same voltage and pulse width.
Further testing will need to be done to determine minimum time between pulses for activating camera and capture.
Some findings are if in still mode and you press capture too quickly it wont take a second picture as it is still storing and it will ignore this 2nd button press. Camera does have 1 LED for power and another one that flashes during video or still capture.
So that was pretty easy, this should hook up to a micro computer fairly easy.
Some ideas would be to mount on my friends RC airplane (as long as he has 2 extra channels), or use as a remote camera with an Arduino, IOIO, Beaglebone or Raspberry Pi. Uses for this thing are almost endless when used with whatever sensor to trigger a capture. The LED that flashes could be used as feedback confirming capture.