help with designing a pcb - how much $$ is fair? - Page 1
Forum section: electronics / beginners

author: DanD
author_rank: Newbie
timestamp: January 24, 2012, 07:06:21 pm
content: Good afternoon friends! I need help designing a circuit for a project I am working on. It is an LED array (actually 12 led's in a row) that is powered by 4 - "aa" batteries and turned on by a keychain remote control. There are bunches out there that do this (light sources for closets, stairways, boat cabins, etc.) and I bought several and took them apart to see how they work - pretty simple and straightforward. I would like to make these changes: once the remote button is pressed, the unit goes on for 60 seconds or so and shuts off. While it is on, I want the led's to sequence or chase; the first led lights up and stays lit, 1/2 second (or sooner) later the second led lights up, etc. until all are lit, then the sequence begins again probably repeating itself 7 or 8 times depending on the delay.From what I have gathered in my endless hours of research it would be better to use an infrared remote rather than an rf remote to preserve battery life. The range is not an issue - 15 feet would suffice however the widest degree possible would be preferred as in some instances I want one click of the remote to activate 2 units simultaneously and they may be 10 feet apart. My questions are:Does this seem complicated or is it pretty simple? If I were to pay an electrical engineer or ?? to design it for me, what would be a fair price to pay? And finally, where would I look or advertise for help with this - could a student at DeVry do this? Thank you for your time-Regards - DanD

author: westfw
author_rank: Super Contributor
timestamp: January 25, 2012, 12:20:29 am
content: QuotePretty simple. It could be done with an Arduino and suitable remote.The devil is in the details. Are you making ONE for your art project, or designing something you hope will be the next be the next big toy? How long a battery life do you need while the lights are off? Safety certifications? What do you actually want when the project is over (a device, a design, and/or a process?) Who owns what when the project is over?Quote$100+ per hour for a 'real' engineering project. Probably $10000 or more to get to the first manufacturing run (more to manufacture overseas.) Not a student project (especially the manufacturing issues.)For just a device (or a couple...)It's within hacker/maker capabilities (whether a student is actually able to make anything is another question.) You buy the Arduino and the IR modules and such, you can probably find someone to put together a device for $100 and a couple (cheap) dinners. Just based on it being a neat idea and a fun diversion, and you know, "free beer"...Or, assorted folks on arduino.cc or similar forums would probably lead you through doing it yourself, all for free. (which is a hell of a bargain, because you'd be getting an education as well as a device.)As to "where"... you probably need someone local. Do you have any local "hacker spaces" ?

author: DanD
author_rank: Newbie
timestamp: January 25, 2012, 05:01:42 am
content: Thanks for the response. After watching one of Dave Jones video blog (#239 I think) where he says to design your project like you will be making thousands of them - components on reels, etc. so I'm thinking along those lines, however I need a couple of working prototypes to see if I can scare up any interest. I found a site that is interesting(www.pcbheaven.com/circuitpages/Miniature_3_Volts_LED_Flasher/) where the battery life is good and it enables the use of rechargeable batteries -- a big plus from a marketing standpoint. I think that circuit may be a good place to start. I want to own everything just in case I catch lightning in a bottle and it is the next big toy and I have a big production run. I saw several of the Arduino posts on utube and I will explore them further. I'm in the Ft. Myers Fl area and there is not a lot of manufacturing down here - I posted on Craigslist and got responses from Dallas, AZ and CA - nothing local so I went to radio shack and bought led's, a solder iron, etc. and started tinkering on my own. I have pieced together a crude unit using plastic sheets cut with my scroll saw and curved and formed (using a candle for heat) and stuffed the battery pack and the led's into it but of course the led's only go on when I flip the switch on the battery pack and they don't blink or chase yet. It has given me the opportunity to think about the case design, the packaging, etc.

author: IanB
author_rank: Super Contributor
timestamp: January 25, 2012, 05:40:18 am
content: Why do you think someone would want to buy this gadget? What is it for and how would it be used?Building on what westfw said, if your purpose is experiment and personal education, then the question is a technical one. But if your purpose is to make a product for sale, then the big questions are to do with business and marketing, and the technical aspects pale into insignificance.

author: westfw
author_rank: Super Contributor
timestamp: January 25, 2012, 07:35:09 am
content: You could add remote control tohttps://www.adafruit.com/products/332for about $5...Ian said it well: from your description, the technical aspects sound like the easy part.

author: DanD
author_rank: Newbie
timestamp: January 25, 2012, 05:26:12 pm
content: Thanks for the input - I checked the adafruit site and searched using "remote control" and got nothing - the /332 was a led belt but no mention of a remote??

author: sonicj
author_rank: Frequent Contributor
timestamp: January 25, 2012, 07:33:54 pm
content: laydyada (adafruit) has a good tutorial on decoding IR signals and integrating with an arduino (microcontroller).this tutorial, an arduino, her $2 IR sensor and a bag of leds would be a good place to start.-sj

author: westfw
author_rank: Super Contributor
timestamp: January 26, 2012, 07:40:31 am
content: Right. The belt is essentially Arduino-controlled. (a 32u breakout; one of the "bastard children" of the arduino family.) There are tutorials on how to do IR remote control of Arduinos. poof!Also check out "DJ Supplies lighting", where fancy LED lights are apparently pretty big business, and SOMEBODY has been having lots of fun designing products. A quick look didn't turn up anything battery-powered, though. (if it doesn't go to 11 and blow the circuit breakers, you didn't buy the right one!)IIRC, There are some companies that hold rather obnoxiously broad and obvious patents re LED color mixing and such :-(

author: DanD
author_rank: Newbie
timestamp: January 27, 2012, 04:50:34 pm
content: Thanks to all - I've got a lot to look at and digest! Hope to see all at next year's CES!! DanD