Arduino Forum

Topics => Product Design => Topic started by: Thomas499 on May 28, 2015, 05:07 pm

Title: Prototype power consumption question
Post by: Thomas499 on May 28, 2015, 05:07 pm
I am interested in learning more about the process of getting an arduino prototype to market. I found a company that can mass produce the electronic side of the prototype, but they can't help design it.

I have the prototype made from arduino parts and shields working. I need the battery to last longer than it currently does though. Ideally the 9 volt battery needs to last at least one year, preferably a year and a half. How would one go by accomplishing this?

The main parts of the prototype consist of an arduino mega2560, and a wi-fi shield. I understand that to meet the power requirements, the arduino will probably need to cut itself off, and activate itself when needed, or at least the wi-fi shield.

How large of a project would this be? Could a college kid working on his forth year of bachelors in electronic do this project? Do I need someone more specialized? Is this a cad project?  Can anyone recommend a good contact that can do this kind of thing?
Title: Re: Prototype power consumption question
Post by: MorganS on Jun 03, 2015, 07:19 am
You might try posting in the "gigs and collaborations" sub-forum.

Start by reading Nick Gammon's power-saving page (http://www.gammon.com.au/power) This will give you some idea of the Arduino chip's capability for low-power aplications.

WiFi is a poor choice for low power. I'm amazed that you can get the battery to last more than a day. To really cut down on the radio's power consumption you need to carefully think about how much it transmits and how often. The guys using the simpler NRF and RFM modules are able to get a pair of AAs to last years by only transmitting for a few milliseconds every few minutes. This means the central server can't ask the remote slave a question until the slave wakes up and dials home.
Title: Re: Prototype power consumption question
Post by: Thomas499 on Jun 03, 2015, 04:15 pm
Quote
Start by reading Nick Gammon's power-saving page This will give you some idea of the Arduino chip's capability for low-power applications.
Thanks! This link is most helpful!

Quote
I'm amazed that you can get the battery to last more than a day
Amazing people is easy. Tell me this, which pin does the Wi-Fi shield use to get it's power? To be more specific, if I wanted to hook up a normally open relay, that only allows power to go to the Wi-Fi shield when that relay is charged, which pin would I target?
Title: Re: Prototype power consumption question
Post by: mixographer on Aug 06, 2015, 08:26 am
Hi Thomas499. 

What you might want to think about doing is getting rid of all the unecessary parts in your project. Especially for power-savings. Even if you turn off the radio components, you're still wasting away most of your energy converting 9v to 5v in the regulator. That turns what little energy there is in a 9v battery into heat. 

Find out what parts of the Arduino board you need (maybe the AVR, an oscillator, some capacitors), find out what components are on the wifi shield, and which ones you need, then design your circuit based on that. 

I know CrossRoads here on the forum offers assistance with board design, send him a PM and see if he can give you an idea of the scope of such a project. This is complicated work, and I wouldn't expect your friend in "electronics" school to do it, but maybe he does RF design as a hobby?

Good luck with your project,

Jimmy