Hiring: Looking for somebody to produce a prototype

Hi there,
I'm very new to arduino. I'm looking for somebody to produce a prototype for a business idea I'm currently working on. To summarise I need a device that will detect a change in voltage/current and communicate via wi-fi or gprs / 3g with my online application. I'm based in central London and ideally I'd like the prototype complete by the end of March. Please email me for further details: (cjburrows21@gmail.com)

Thanks

Chris

To summarise I need a device that will detect a change in voltage/current

AC or DC? Microvolt or megavolt? Microamp or megaamp?

and communicate via wi-fi or gprs / 3g with my online application.

Ethernet is cheaper and simpler. Is that not an option?

Hi Paul,
Thanks for getting in touch, two good questions which I'll answer by explaining my requirements a bit more because I'm not sure of the technical answers myself. I want a device that I can plug a household appliance (say a kettle or toaster) into that will detect when it has been used. On detecting usage I want it to use wifi (if it's available) or the built in sim card and send a message to my online system so I can log the usage. I'm pretty open to how the communication will work. I hope that answers your questions in a round about way.

Thanks

Chris

I want a device that I can plug a household appliance (say a kettle or toaster) into that will detect when it has been used.

  • Detection it has been used can also doen by only monitoring the current - ==> no voltage detection needed
  • do you want to know how long it is used ==> clock
  • do you want local logging - in case wifi doesn't work ==> SD card?
  • do you want a local display?

2 cents

Hi,
I just need to know the appliance was used so timing won't be necessary. Local logging could be good and then queue the messages to send when connectivity is back. Open to measuring voltage or current whatevers best. Any takers?

Thanks

Chris

So not entirely unlike Google PowerMeter, Cent-A-Meter, Tweet-A-Watt, Kill-A-Watt, etc.?

I think CJ's looking to make a device for monitoring someone's status without his having to call in.
Someone gets up and turns on the TV, or the tea kettle, or the toaster, ordinarily/daily and that equates to all's well ["I got up this morning!"]. and failing to do so signals something out of the ordinary (maybe he needs help, etc.)

1st order price indication BOM for prototype

wifishield E70
Arduino E25
SDcard E10
Sensor E10
Housing E10
PowerSupply E5
Cabling etc E10

E150 --> 50% is the wifi !!

Hi Rob,
Thanks for the first indicative prices, what does BOM mean and I'm guessing E is for euros. Do you have any idea of labour time and costs associated to it. Are you interested in taking this further?

Thanks

Chris

Runaway pancake; pretty much that hit the nail on the head!

BOM == Bill Of Materials

Do you have any idea of labour time

Is your goal a proof of concept or a reliable device. The first can be build in a week or 2 (if materials are available) by someone familiar with techniques, making it reliable, tested and/or presentable to investors multiply that by 5.

PS. I did not include Hofstadter's law :wink:

and costs associated to it.

2 full time weeks to prototype x freelance hour price = ~5000E excl. travel costs etc. 10 weeks ~20KE (free lance prices drop a bit for longer periods).
[ok, there are many people - who want to do it for less]

Are you interested in taking this further?

dont know, What is the time schedule?

I would suggest using a Bluetooth communication means than the Wifi not only Bluetooth is easy to implement its cost effective too just because of that USB Host shield i think 30(max rate) dollars(host shield) + 8(bluetooth dongle) will do the trick or even use a radio module (OP can think of it?)

Hofstadter's law

Also quantified as "The first 90% of the project will take 90% of the available time, and the remaining 10% of the project will take the remaining 90% of the time available".

And then there's my "two, two and a half" law.

Every project will take twice as long and cost twice as much as planned, and it will earn half as much as expected.


Rob

A poorly planned project can take three times as long as the plan calls for. A well planned project takes only twice as long.

Or:

Quality product
On time
On budget

You only get to pick two, at most!

Quality product
On time
On budget

You only get to pick two, at most!

Affirmative!

A well planned project would take into consideration potential problems and extend its time to compensate in the planning stages, then if it all went well you get congratulated for bringing in in early.