Author Topic: Open Source Multimeter  (Read 238481 times)

0 Members and 1 Guest are viewing this topic.

Offline House91320

  • Regular Contributor
  • *
  • Posts: 176
Open Source Multimeter
« on: June 30, 2011, 05:05:19 pm »
My friends and I have been developing an open source multimeter. I wanted to do a case design for a kick starter video, and i would like people to tell me what they think of the case so I can make it look as good as possible.
« Last Edit: June 30, 2011, 05:09:28 pm by House91320 »
 

Offline ndictu

  • Regular Contributor
  • *
  • Posts: 210
  • Country: sk
Re: Open Source Multimeter
« Reply #1 on: June 30, 2011, 05:19:42 pm »
Please don't be yet another one of those kickstarter projects that only have a rotating CAD model and long FAQ with answers to the most minutiae details, but no real proof-of-concept design.
 

Online Zero999

  • Super Contributor
  • ***
  • Posts: 15854
  • Country: gb
  • 0999
Re: Open Source Multimeter
« Reply #2 on: June 30, 2011, 05:24:08 pm »
It looks like a children's toy but it's only a prototype model.

How much are you planning to sell it for?
 

Offline House91320

  • Regular Contributor
  • *
  • Posts: 176
Re: Open Source Multimeter
« Reply #3 on: June 30, 2011, 05:30:42 pm »
Don't know yet i have to figure out the manufacturing cost.
 

Offline FreeThinker

  • Frequent Contributor
  • **
  • Posts: 791
  • Country: england
  • Truth through Thought
Re: Open Source Multimeter
« Reply #4 on: June 30, 2011, 05:51:49 pm »
My first question would be  WHY? The top end of the market is well served by the likes of Fluke et al. The budget end of the market is VERY price conscious and the low end is awash with One Hunglow Tat. This leaves the speciality sector, low volume and usually high accuracy. Without a very tight spec and a definite market to aim at you may find finance a rare resource.
Machines were mice and Men were lions once upon a time, but now that it's the opposite it's twice upon a time.
MOONDOG
 

Online Zero999

  • Super Contributor
  • ***
  • Posts: 15854
  • Country: gb
  • 0999
Re: Open Source Multimeter
« Reply #5 on: June 30, 2011, 05:59:57 pm »
A good open source oscilloscope would be nice.
 

Offline FreeThinker

  • Frequent Contributor
  • **
  • Posts: 791
  • Country: england
  • Truth through Thought
Re: Open Source Multimeter
« Reply #6 on: June 30, 2011, 06:59:28 pm »
A good open source oscilloscope would be nice.
Again WHY? For the same reasons above they are just not cost effective. Unless you are doing it just for chuckles it makes no sense to me , sorry.
Machines were mice and Men were lions once upon a time, but now that it's the opposite it's twice upon a time.
MOONDOG
 

Online Zero999

  • Super Contributor
  • ***
  • Posts: 15854
  • Country: gb
  • 0999
Re: Open Source Multimeter
« Reply #7 on: June 30, 2011, 07:00:36 pm »
There's the Nano, a crap open source 'scope so why not do the same thing with higher spec' hardware?
 

Online mikeselectricstuff

  • Super Contributor
  • ***
  • Posts: 12562
  • Country: gb
    • Mike's Electric Stuff
Re: Open Source Multimeter
« Reply #8 on: June 30, 2011, 07:21:04 pm »
A good open source oscilloscope would be nice.
Again WHY? For the same reasons above they are just not cost effective. Unless you are doing it just for chuckles it makes no sense to me , sorry.
A scope has MUCH more potential as an OS project as a lot of the cost on higher end commercial units is for software functionality. For the hardware cost of a Rigol you could in principle build something with the performance and features of a scope several times the price, although it would be a lot of work
A DMM seems pretty pointless as I can't see what you can do better/cheaper than what's already out there.
Youtube channel:Taking wierd stuff apart. Very apart.
Mike's Electric Stuff: High voltage, vintage electronics etc.
Day Job: Mostly LEDs
 

Offline FreeThinker

  • Frequent Contributor
  • **
  • Posts: 791
  • Country: england
  • Truth through Thought
Re: Open Source Multimeter
« Reply #9 on: June 30, 2011, 07:44:35 pm »
A good open source oscilloscope would be nice.
Again WHY? For the same reasons above they are just not cost effective. Unless you are doing it just for chuckles it makes no sense to me , sorry.
A scope has MUCH more potential as an OS project as a lot of the cost on higher end commercial units is for software functionality. For the hardware cost of a Rigol you could in principle build something with the performance and features of a scope several times the price, although it would be a lot of work
A DMM seems pretty pointless as I can't see what you can do better/cheaper than what's already out there.
Hmm! Good point. Do you really think that SIGNIFICANT savings could be made in the hardware (without  cutting corners) to justify the effort of a home brew software firmware? I think Rigol do a pretty good job of squeezing every last cent out of there product (performance wise) and think they would be a hard act to beat. As a kickstarter project you need a significant edge, I just don't see it.
Machines were mice and Men were lions once upon a time, but now that it's the opposite it's twice upon a time.
MOONDOG
 

Online mikeselectricstuff

  • Super Contributor
  • ***
  • Posts: 12562
  • Country: gb
    • Mike's Electric Stuff
Re: Open Source Multimeter
« Reply #10 on: June 30, 2011, 07:49:13 pm »
A good open source oscilloscope would be nice.
Again WHY? For the same reasons above they are just not cost effective. Unless you are doing it just for chuckles it makes no sense to me , sorry.
A scope has MUCH more potential as an OS project as a lot of the cost on higher end commercial units is for software functionality. For the hardware cost of a Rigol you could in principle build something with the performance and features of a scope several times the price, although it would be a lot of work
A DMM seems pretty pointless as I can't see what you can do better/cheaper than what's already out there.
Hmm! Good point. Do you really think that SIGNIFICANT savings could be made in the hardware (without  cutting corners) to justify the effort of a home brew software firmware? I think Rigol do a pretty good job of squeezing every last cent out of there product (performance wise) and think they would be a hard act to beat. As a kickstarter project you need a significant edge, I just don't see it.
I think the key would be clever people doing smart stuff in FPGAs - The Chinese makers are not good at innovating- it;s always cheaper versions of higer-end stuff with poorly designed software. You're never going to get  insane bandwidths as you're constrained by available ADCs, but I think there is plenty of scope to get things like good update rates and DPO type functionality, as well as lots of protocol analysis type functions, which are the sort of things that come as high-cost add-ons to current scopes.
Youtube channel:Taking wierd stuff apart. Very apart.
Mike's Electric Stuff: High voltage, vintage electronics etc.
Day Job: Mostly LEDs
 

Offline FreeThinker

  • Frequent Contributor
  • **
  • Posts: 791
  • Country: england
  • Truth through Thought
Re: Open Source Multimeter
« Reply #11 on: June 30, 2011, 07:49:22 pm »
There's the Nano, a crap open source 'scope so why not do the same thing with higher spec' hardware?
What? Make a crap high end scope? :o ;D. Sorry I'm in a funny mood tonight!
Machines were mice and Men were lions once upon a time, but now that it's the opposite it's twice upon a time.
MOONDOG
 

Offline FreeThinker

  • Frequent Contributor
  • **
  • Posts: 791
  • Country: england
  • Truth through Thought
Re: Open Source Multimeter
« Reply #12 on: June 30, 2011, 07:52:47 pm »

I think the key would be clever people doing smart stuff in FPGAs - The Chinese makers are not good at innovating- it;s always cheaper versions of higer-end stuff with poorly designed software. You're never going to get  insane bandwidths as you're constrained by available ADCs, but I think there is plenty of scope to get things like good update rates and DPO type functionality, as well as lots of protocol analysis type functions, which are the sort of things that come as high-cost add-ons to current scopes.
Well that rules me out! :'(.
Machines were mice and Men were lions once upon a time, but now that it's the opposite it's twice upon a time.
MOONDOG
 

Offline Kiriakos-GR

  • Super Contributor
  • ***
  • !
  • Posts: 3525
  • Country: gr
  • User is banned.
    • Honda AX-1 rebuild
Re: Open Source Multimeter
« Reply #13 on: June 30, 2011, 08:06:10 pm »
I wanted to do a case design for a kick starter video, and i would like people to tell me what they think of the case so I can make it look as good as possible.

Well I think that I am looking at one Gossen range switch,
plus the bottom of the Fluke 28II painted red, with out the holster, and a bit more square !!  :)

Well I have a tip for you,  you are in a good path, but you have to surprise us !!
Yes SURPRISE US !!

Its hard to happen,  but if you are serious in what you do, it will not be that difficult.   
If you like to know what to avoid ?  Look at Extech.   ;)
 

Online ejeffrey

  • Super Contributor
  • ***
  • Posts: 2491
  • Country: us
Re: Open Source Multimeter
« Reply #14 on: June 30, 2011, 08:14:46 pm »
There's the Nano, a crap open source 'scope so why not do the same thing with higher spec' hardware?

The nano already costs $100, and doesn't have a real scope AFE and has a pathetic sample rate, and only one channel.  Put real spec hardware in there, and you are increasing the cost a lot.

Quote from: FreeThinker
Hmm! Good point. Do you really think that SIGNIFICANT savings could be made in the hardware (without  cutting corners) to justify the effort of a home brew software firmware? I think Rigol do a pretty good job of squeezing every last cent out of there product (performance wise) and think they would be a hard act to beat.

No, I don't think you can make the equivalent of the 50 MHz Rigol for less than the market price, just based on parts cost alone, at least not in the volume a small open hardware project would get.

The bottom end of the market is under tremendous price pressure.  Manufacturers are basically selling their cheapest models near cost (at their much larger volumes) and making their profit and recovering the development costs on the premium for higher end features -- extra channels, extra bandwidth, mixed signal, and so forth all cost proportionally more than the base model.

So I think the only place you could attack the scope market is to aim higher, and especially with analysis tools.  If you had a few really good mixed signal designers who had been made independently wealthy and wanted to build an open hardware oscilloscope platform in their free time, you might be able to design something like a 4 channel, 200 MHz mixed signal scope where the production costs were less than a comparable commercial unit.  They key then would be to be able to add in all of the bonus firmware stuff for free: the measurements, the pass/fail analysis, and the protocol decoders. 

If you did that right, you might end up with something that had the hardware cost and specs of the 200 MHz/4 channel Rigol, but all the unlock codes from the Agilent 3000X.  Of course, you aren't going to get the obscene waveform update rate and real-time advanced triggering and protocol decoding without the agilent ASIC.

There are two problems with this: it takes a really talented team a long time to design something that has the functionality of a higher end scope.  You have to find those guys and convince them to work for free.  Second, the scope you build is still going to end up costing considerably more than the $400 a lot of hobbyists already balk at paying.  You might end up with the most powerful $1600 scope that nobody buys because the target audience can't afford it, and the people who can afford it and want the features are more interested in getting a name brand scope with support than a hackable open platform.  Plus you still have to contend with the problem that the big players are sitting there with their ASICs that you can't match in terms of performance.
 

Offline tnt

  • Regular Contributor
  • *
  • Posts: 239
Re: Open Source Multimeter
« Reply #15 on: June 30, 2011, 08:54:06 pm »
Personally I'm convinced that an open source scope would be a good thing.

You're not going to get the low end market, I'd target something like 5000$ or so unit cost (I mean you do have to recoup the dev cost as well). But you could have in it a lot of the functionality of much higher priced scopes. Sure not every hobbyist is gonna buy it ... but I'm convinced there is enough of a market for it anyway. (I'm just a hobbyist/hacker and I have a 7500$ scope ...)

If you do the design modular enough (mostly front end separate from the acq) to allow modules for scope / logic analyzer / spectrum analyzer / ...

The agilent asic function could all be replaced by a good FPGA (I did and still do FPGA design for a living so I know what I'm saying). Agilent went the asic way because it's much cheaper given the volume they have and they're all about having more margin. But for a project like this, even 500$ of FPGA cost would be acceptable and for that price, you get a pretty good one that can definitely compute your 800x600 image composite of 50k wfrm/s in its internal memory.
 

Offline ivan747

  • Super Contributor
  • ***
  • Posts: 2027
  • Country: us
Re: Open Source Multimeter
« Reply #16 on: June 30, 2011, 10:58:40 pm »
There's the Nano, a crap open source 'scope so why not do the same thing with higher spec' hardware?
What? Make a crap high end scope? :o ;D. Sorry I'm in a funny mood tonight!
So am I! I have trolled all over the forum! Sorry.
 

Offline vtl

  • Regular Contributor
  • *
  • Posts: 136
  • Country: au
Re: Open Source Multimeter
« Reply #17 on: July 01, 2011, 02:21:42 am »
Markets pretty saturated for multimeters, how about a decent LCR meter that does ESR as well? Make it cost under $100 and you got a winner, seems like you have to pay double or triple that for something worthwhile.
For a hobbyist it doesn't sound great to spend that much to measure the ESR of a 10c cap of old electronics.
 

Online Zero999

  • Super Contributor
  • ***
  • Posts: 15854
  • Country: gb
  • 0999
Re: Open Source Multimeter
« Reply #18 on: July 01, 2011, 03:59:06 pm »
It would have to do RMS measurements too.
 

Offline Afrotechmods

  • Supporter
  • ****
  • Posts: 44
  • Country: 00
    • Afrotech
Re: Open Source Multimeter
« Reply #19 on: July 01, 2011, 07:27:30 pm »
As has been said before, I don't think you will actually be able to come up with a solution that will ever be able to compete with $40 off the shelf meters which are manufactured in quantities of 100+k.

However! I would like to applaud you for what you are doing anyway, because I think the real value in this project is the educational value. If you are able to document the project and the design process thoroughly it would be a cool thing to learn from. You could make money from putting ads up on the webpage documenting the project. I am particularly interested in the process of how you will design the case and get it manufactured, as industrial design is something I never got a chance to study in school.

Now to answer your questions, I think the design you've got so far looks pretty good. What does the D stand for by the way? Diode? If so, I recommend using the diode symbol instead. Also, I am used to seeing ºC instead of TMP.
The bright red on black looks a bit jarring. Perhaps a slightly more subdued red would look better.
 

Offline FreeThinker

  • Frequent Contributor
  • **
  • Posts: 791
  • Country: england
  • Truth through Thought
Re: Open Source Multimeter
« Reply #20 on: July 01, 2011, 07:55:55 pm »
As has been said before, I don't think you will actually be able to come up with a solution that will ever be able to compete with $40 off the shelf meters which are manufactured in quantities of 100+k.

However! I would like to applaud you for what you are doing anyway, because I think the real value in this project is the educational value. If you are able to document the project and the design process thoroughly it would be a cool thing to learn from. You could make money from putting ads up on the webpage documenting the project. I am particularly interested in the process of how you will design the case and get it manufactured, as industrial design is something I never got a chance to study in school.

Now to answer your questions, I think the design you've got so far looks pretty good. What does the D stand for by the way? Diode? If so, I recommend using the diode symbol instead. Also, I am used to seeing ºC instead of TMP.
The bright red on black looks a bit jarring. Perhaps a slightly more subdued red would look better.
As I understand it it's a kickstarter project.. he's looking for finance.
Machines were mice and Men were lions once upon a time, but now that it's the opposite it's twice upon a time.
MOONDOG
 

Offline Bored@Work

  • Super Contributor
  • ***
  • Posts: 3933
  • Country: 00
Re: Open Source Multimeter
« Reply #21 on: July 01, 2011, 08:40:11 pm »
As I understand it it's a kickstarter project.. he's looking for finance.

But the issues are the same. Would you finance a development which has that much >< of a change to become profitable?
I delete PMs unread. If you have something to say, say it in public.
For all else: Profile->[Modify Profile]Buddies/Ignore List->Edit Ignore List
 

Offline FreeThinker

  • Frequent Contributor
  • **
  • Posts: 791
  • Country: england
  • Truth through Thought
Re: Open Source Multimeter
« Reply #22 on: July 01, 2011, 09:01:46 pm »
As I understand it it's a kickstarter project.. he's looking for finance.

But the issues are the same. Would you finance a development which has that much >< of a change to become profitable?
Exactly my point. See my first post :D
Machines were mice and Men were lions once upon a time, but now that it's the opposite it's twice upon a time.
MOONDOG
 

Offline tinhead

  • Super Contributor
  • ***
  • Posts: 1926
  • Country: 00
    • If you like my hacks, send me a donation
Re: Open Source Multimeter
« Reply #23 on: July 01, 2011, 10:06:25 pm »
there is handheld open source scope "ourdso", v2 is the latest revision, Based on Cyclone EP2C8Q208, as ADC the good known AD9288 (so 2 x 100MSs).
Based on NIOS , 320x240 ... far from perfect but it works already suficient. All sources available and actually can be easy modified to
support e.g. 2 x 500MSs or even 2 x 1GSs ADC, whatever.

But open source DMM ? For what reason ? Buy a 5USD single-chip DMM, few good resistors , attach cheap 8bit µC and here we go - DMM ready.
I don't want to be human! I want to see gamma rays, I want to hear X-rays, and I want to smell dark matter ...
I want to reach out with something other than these prehensile paws and feel the solar wind of a supernova flowing over me.
 

Online Zero999

  • Super Contributor
  • ***
  • Posts: 15854
  • Country: gb
  • 0999
Re: Open Source Multimeter
« Reply #24 on: July 02, 2011, 07:58:57 am »
But open source DMM ? For what reason ? Buy a 5USD single-chip DMM, few good resistors , attach cheap 8bit µC and here we go - DMM ready.
I don't think he's talking about building a basic meter.

I often think with Fluke, you're just paying for the name most of the time. It's true that Fluke offers good safety features and excellent accuracy which is why they're popular but they don't really cost much to build. A Chinese company could probably build a meter with the same accuracy and safety features as a Fluke but it's not worth their while as the kind of people who want them would just buy a Fluke and the cheap hobbyists would just buy a cheaper Chinese meter which doesn't have them.

I think an open source meter with the same accuracy and safety features of a Fluke would sell because people would be able to see the the quality of the components and would know that it's got the protection of a Fluke but at a lower price.
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf