I’m in the early stages of a home electronics project and I’ve hit a brick wall, Thought I’d drop a quick note on here to see if anyone has any ideas!
Project:
I’m on off-road enthusiast and a chartered electronic engineer. I decided recently, that I wanted to fit a few video cameras to my car help with my off-roading. The idea is to fit two cameras to the underside of each wing mirror – one pointing at the front wheel and one pointing at the rear wheel. This would (hopefully) reduce the need to have someone ‘spotting’ for me when I’m crawling over rocks and the like.
Requirements & Constraints:
- I want the video to appear on my 9” android tablet, which already has a mount on the dash.
- Video to be as high quality as possible
- Video refresh rate to be 3 times per second as a minimum, but much higher ideally
- The tablet needs an internet connection via wifi, hence the cameras need to sit on an existing network.
- Low cost solution (i.e. £10s or £100s acceptable, £1000s not…)
The Problem:
In a nutshell, getting analogue video to appear on my android tablet.
Things I’ve considered:
- IP cameras. I considered buying a few off-the-shelf IP cameras and ripping them apart, boxing up the electronics and coming up with a way to replace the stock image sensor with some waterproof external image sensor that I can mount under the mirror. I decided this was probably unlikely to succeed given the environment (frequent cold/hot cycles etc found in cars). Plus it’s hardly an elegant solution.
- In-vehicle DVR. This looked promising, there are a great variety to choose from on ebay/amazon & Alibaba. Problem is that they all output in VGA or Composite so it still leaves me in the Analogue domain.
- Domestic DVR. This idea was to get a domestic/commercial type CCTV DVR with a network connection and then hide it in the car somewhere. Downsides are relatively long boot times, and the devices are designed to be ‘always on’ – so im not convinced it will behave properly with frequent power cycles. Also I’d need a WIFI network bridge – which adds some complexity and I’ve had poor experience with these devices in the past.
- In-car PC. This seemed like the holy grail – I found a ruggedised PC designed to be used in vehicles that came with a mini internal UPS, a PSU designed to work with vehicles (i.e. an ignition feed, so it shut down properly when power was removed), a 4 channel video capture card, a 4G modem, a WIFI adaptor and an -40’C/+50’C operating envelope. Unfortunately that configuration came in it around the £1100 mark which is just too expensive. Keeping my eyes peeled on ebay for a second hand one though….
- Raspberry Pi. Similar to the PC I wondered if I could attached a video capture USB dongle to a Pi and use it to stream the video over WIFI. Seemed like a good idea but all my investigations found that it introduced a 500ms/1s delay to the feed – which is no use for this application.
- AV / WIFI converter. I've searched far and wide for these and only really found one that looks appropriate (or several suspiciously similar devices anyway). The problem with them is that they all form a new wifi hot spot - i.e. they're not capable of joining an existing network, so i'd loose my internet connectivity when viewing them on the tablet and would have to change networks to view different cameras - which is not ideal
The Question:
Does anybody have any more ideas for getting a CCTV/TV, Composite video or some other analogue format into the digital domain – ideally broadcast of IP in a similar way to IP security cameras?
Thanks in advance,
James
