Thank you for being a valued part of the CNET community. As of December 1, 2020, the forums are in read-only format. In early 2021, CNET Forums will no longer be available. We are grateful for the participation and advice you have provided to one another over the years.

Thanks,

CNET Support

Question

What is the best way to go about making a speed monitor?

Nov 25, 2014 5:27PM PST

Hey ya'all..

I have this project idea I want to design and need your assistance in finding the most feasible way of doing it..

Okay the project is to design a system that captures the speed of a car (or any road vehicle) and sends it a computer that has software which 1) determines the location of the vehicle and (can maybe use a map interface to show the location kinda like Google maps Happy) and 2) reports via the GUI whether the vehicle is speeding or under the speed limit...and prints out a log Happy...

My questions are are:
1) How to easily construct the gauging and transmitting device...and possible programming options (for instance, will i require custom made microchips or maybe write code that can be integrated with a sim card (GSM) usage, etc)

2) What is the best and far reaching communication method that the transmitter on the vehicle can use to communicate with the computer/server? (Taking into account long distances, costs and usability)

3) and ideas on the operating software, how it receives, deciphers and reacts to the info from the transmission device and GUI?

Discussion is locked

- Collapse -
Clarification Request
In the UK
Nov 25, 2014 5:51PM PST

Here in the UK the Police and Local Authorities already use similar systems.

Speeding on motorways, speed trap cameras can capture vehicle registration numbers, and speed at the time and date,of the alleged offence, grab vehicle owner details from DVLC and send a notice of speeding/fine direct to the offender/owner.

London Metropolitan Area, has automatic vehicle recognition camera systems throughout Inner and Outer London to capture and charge vehicle owners the London Congestion Charge.

So, such systems are already in place. Are you reinventing the wheel?

Mark

- Collapse -
Not sure the OP wants to trap speeders, but,
Nov 25, 2014 10:13PM PST

more of a location type system to track the movements of vehicles.

That said, there are many systems that already do this.

LoJack, a system to track stolen vehicles and OnStar spring to mind but there are many more.

http://en.wikipedia.org/wiki/Vehicle_tracking_system

Perhaps the OP is doing this as some sort of project.

P

- Collapse -
your getting there :-)
Nov 26, 2014 12:36AM PST

Thanks

the idea is centrally about tracking movement in regard to speeding...

take it this way, the device sends the speed and location to the master computer which runs the data against road networks and sanctioned speeds to the respective road the car is in and then automatically logs that... like an ever present cop... always there... Happy

- Collapse -
Re-read please :-)
Nov 26, 2014 12:30AM PST

thanks for reading...but it seems you didnt understand....

there is no reinventing the wheel here because you system/s are all camera based... i am making a device that can be attached to the car therefore giving a kinda omnipresent traffic cop... your speed traps only work where they are installed... my system is to have the car monitored nomatter where it goes...

please feel free to ask more,

just know that i am far from trying to re-invent anything Happy

- Collapse -
Sounds close to a speed+GPS logger.
Nov 26, 2014 12:34AM PST

During some long car trips I installed a GPS logger in my Android phone. Along with the location data it logged the speed as well as GPS location. I think it went down to 15 or less second intervals. This means such logging is already out there.

On a side question, ever watch Demolition Man? It had a ticket dispenser built in to the car as well.
Bob

- Collapse -
YESSSSS!!!! Exactly like that
Nov 26, 2014 12:41AM PST

Yes BOB.. something like that... the only problem with GPS is the lag in time when satellites are out of range and all that... i want a way of building a real time system on a big scale for instance over an entire city...

- Collapse -
5 second interval is not enough?
Nov 26, 2014 12:49AM PST

I guess one could tap into the OBD port but given that tar pit I know better. Some folk must learn why on their own.

We used the GPS system to build such loggers for commercial apps (no I can't reveal who I did the work for but can share experiences) and once in a while you encounter someone that wants below 1 second reporting. That would be very expensive and no one has delivered enough suitcases of cash for it.
Bob

- Collapse -
ooopss sorry...
Nov 26, 2014 2:31AM PST

oh you said at 5 second intervals? thats sweet!!! tell me from your experience what kind of device i could use...i was wondering about SW radio frequencies and how i can use them to send the signal... a little ambitious i know but hey Happy

- Collapse -
We built a few custom models.
Nov 26, 2014 5:24AM PST

The rigs are custom SBCs with custom apps but the data is buffered then sent in blocks over a cellular data connection.

You asked about SW frequencies but a custom radio and it's certification is now over a million bucks today. I haven't found any company that's willing to burn that much cash.

Now if you take some under 99 buck Android phone, you have the basic bits and can craft what would rival what we did over the years.
Bob

- Collapse -
Interesting...
Nov 26, 2014 3:21PM PST

i hear you Bob...and your system sounds doable!!! Happy

the reason i wanted to make use of SW frequencies is that they can be picked up anywhere in the world without use of complicated equipment...you know thats like why radio enthusiasts and independent radio stations (like the ever elusive number stations) use SW, they are available and anyone anywhere can pick it up... thus my system can be deployed over a large area...an entire country if one so wishes...

thats where my idea came from....but your idea of going GSM on this sounds much more feasible...i was just wondering wont it need some licenses or heavy receiver for cellular data connection....

- Collapse -
Sorry.
Nov 26, 2014 3:35PM PST

Data over cellular is very easy with a cheap android phone. What you seem to be driving at is a customized system. Those mean a few million to get engineered so while I know this area I wonder if you have the investors and enough sales to make it worth while.
Bob

- Collapse -
Sort of..
Nov 26, 2014 4:04PM PST

Investors are in the pipeline but as you know with all "Mr Moneybags", they want to spend on something they can see...

Me and my team can write a fully detailed design and even do some visualizing with CGI but what we need the most as to build a proof of concept prototype... so even if the system will be expensive to make and implement, the monetary input will be catered for...what i need is a full-proof concept that we can initiate on a small scale (as small as one car, in a 5km {3 miles} radius) just as a prototype

- Collapse -
So why not go with a POC?
Nov 26, 2014 4:07PM PST

We used many hundred buck cellular modems and a SBC to build the first POC. Today you could gen it up with an Android phone for cheap. Today I could pick up a 50 buck phone from Ting, write code and rival/exceed what we did a few years ago.
Bob

- Collapse -
Thanks Bob...
Nov 26, 2014 5:14PM PST

Okay that sounds awesome...we will design the initial prototype concept and keep you in the loop if you are interested..

thanks a mil... Happy

- Collapse -
While Short Wave radio signals have the capability
Nov 26, 2014 11:14PM PST

of being picked up all over the world, HAM operators and the elusive number stations use specific frequencies to communicate with specific places at specific times of the day and specific times of the year.

Receiving equipment is relatively cheap but transmitting equipment is expensive and would require a large antenna.

You may also run into licensing issues with the SW transmitters due to National restrictions on frequency use and certification of operators.

Cellular, as already noted, would be much cheaper and easier.

Just saying.

P

- Collapse -
check trucker sites
Nov 27, 2014 1:59AM PST

many trucks have time and speed recording boxes installed into them, and wifi has been added to the newest versions along with GPS. Also car rental sites have this on their cars, so they can find them and know if they've been driven at illegal speeds. Some cars on lease now have this installed in them, and not every lease knows it.

https://www.google.com/search?q=tracking+rental+cars+gps+speed&gws_rd=ssl

https://www.google.com/search?q=tracking+rental+cars+gps+speed&gws_rd=ssl#q=tracking+commerical+trucks+gps

- Collapse -
see this video on one system
Nov 27, 2014 2:02AM PST