Please recommend oscilloscope for robotics research

[rstofer]

I would design the measurement capability into the individual drivers.  The high side current sense amplifier and some kind of voltage measurement would be easy to add.  In fact, I can see an I2C bus running around to the various drivers and interrogating ADCs.  Maybe I would route a 'trigger' around such that all measurements are taken at the same time.  In fact, I would just put a small uC on each driver which would already have a suitable ADC.

Suppose I did put extra hardware, including an uC at each driver.  I could do something really neat by adding RS485 and having a multi-master network.  Doing this would allow me to interact with the uCs with some kind of RS485 driver on any PC USB bus.

Having the data readily available opens up the opportunity for logging and reporting.

I'm not sure how this thing would go because I have no idea about what is being built.  I could see WiFi as a communication strategy, all I would need is a TCP connection to grab the data.

A scope would be a necessary tool for some part of the project but not for data logging.

[saturation]

You can get data logging power meters from the same sources I mentioned.  Also most Agilent DMM's can log as well as send log data via bluetooth, even its low cost ones.  The GWInstek 1054B has a logging app included.

The real question you need ask is is how much time of log data will you collect, what accuracy do you need, digits, is it data points or waveforms?  If unlimited or undefined you'll need it logged to a PC, which has buku memory via its hard drive for data or full waveforms.  Many stand alone loggers have limited local memory, is that long enough for your purpose? 

E.g. the 1054B has a logger for ~ 100 hours [ i.e., 4 continuous days] of waveforms, not just data points. 

In the USA, not as popular as the Rigol, it available discounted from Tequipment, just ask for a price lower than listed.

I want to do sensory motor integration and motor control at home. Besides, I need a scope to test some circuits. As for the reason for data logging, I want to publish the data in academic reports. So, being able to store the data to a computer would be desirable. I guess I should not spend more than 3K. Of course, if paying a bit more makes a big different, I would consider it.

[JPortici]

I would design the measurement capability into the individual drivers.  The high side current sense amplifier and some kind of voltage measurement would be easy to add.  In fact, I can see an I2C bus running around to the various drivers and interrogating ADCs.  Maybe I would route a 'trigger' around such that all measurements are taken at the same time.  In fact, I would just put a small uC on each driver which would already have a suitable ADC.

i would do this as well. you need it anyway if you don't want to bother with current probes and/or lots of wires hanging around, which also get quiclky very impractical. how then they send the data to the computer or other unit is up to you

[Fungus]

I would design the measurement capability into the individual drivers.

Me too. Not all motors will have equal consumption (it depends on load) so looking at them in groups won't be very useful.

Each motor should probably have a small microcontroller attached to it for position control. You can add in power measurement as well.

Network them all together and you have full monitoring. No need for an oscilloscope.

The oscilloscope will be used for debugging the communications network, a DS1054Z is perfectly capable of that.

[rstofer]

Of all the ways to communicate between a PC and the world, a USB HID device is about the easiest to implement.  Among many other boards, the Teensy boards can do this nicely:
https://www.pjrc.com/teensy/rawhid.html

https://www.pjrc.com/store/teensy32.html

I'll leave reading through the 1100 page manual to others but it appears that the chip has 16 bit ADCs:
https://www.pjrc.com/teensy/K20P64M72SF1RM.pdf

I used a much older Teensy and the HID interface to tie physical knobs and dials to Microsoft Flight Simulator so coding for HID must have been pretty easy.

It would be worth verifying which versions of Teensy support the RAW HID code.

[eeguy]

For general purpose testing of electronic circuits, sensors, motor controllers and motors, would you recommend the DSOX2012A (100MHz, 1Mpts, 2GSa/s), 2022A (200MHz, 1Mpts, 2GSa/s) or the 3012T (100MHz, 4Mpts, 5GSa/s)? Not sure if it is worth to spend that much money on the 3012T.

How is the quality of Rigol and GW Instek scopes? Tektronix was very famous many years ago but it seems that their scopes are not popular anymore. What is wrong with Tektronix scopes?

[TheSteve]

If you're going to up your budget how about a used DSOX3014A from ebay etc?

[nctnico]

How is the quality of Rigol and GW Instek scopes? Tektronix was very famous many years ago but it seems that their scopes are not popular anymore. What is wrong with Tektronix scopes?

The build quality of Rigol and GW Instek is just fine.

Tektronix used to make great scopes but their current offerings (not just their scopes!) are very poor value for money and it seems they are only selling to universities and schools nowadays. I wouldn't be surprised if Tektronix' T&M division gets bought by another T&M manufacturer because the brand name still has value.

[Wuerstchenhund]

For general purpose testing of electronic circuits, sensors, motor controllers and motors, would you recommend the DSOX2012A (100MHz, 1Mpts, 2GSa/s), 2022A (200MHz, 1Mpts, 2GSa/s) or the 3012T (100MHz, 4Mpts, 5GSa/s)? Not sure if it is worth to spend that much money on the 3012T.

That is difficult to say without knowing what exactly you will be working on. For very basic tasks the DSOX2k is fine, but it comes with very small memory and comes with some limitations (IIRC serial decode only works on analog channels) that make it less suitable for more complex tasks. It's not a bad scope per se but these days I'd rather get a GW Instek GDS-2000E which has more memory.

And as said before the DSOX3kT is very expensive for a scope with just 4Mpts of memory. The much better alternative is the LeCroy WaveSurfer 3000 but I guess you have reasons for not considering it.

How is the quality of Rigol and GW Instek scopes?

GW Instek has been around for a long time, like Hameg (now owned by R&S) they pretty much foxus on entry-level instruments. The build quality has always been good from what I know. Support had been a bit spotty but that was probably 10 years ago, and since then they have made lots of improvements and now are very responsive.

Rigol, well, I think the build quality is good. What would concern me more is that they are apparently unable to properly design their hardware (search for 'Project Yaigol'). Also, pretty much all their products come to market in a bug-infested state, and it can take a while until the worst ones get fixed (and some are probably never fixed, like ETS on the DSO6000). Rigol is cheap, the scopes are widespread amongst hobbyists, and they can be hacked.

Tektronix was very famous many years ago but it seems that their scopes are not popular anymore. What is wrong with Tektronix scopes?

As I already said above, Tek was famous when analog scopes were still a thing, and Tek has made the best analog scopes that were ever made, sometimes using some very sophisticated technology for back then. But Tektronix never really made the mental jump to digital, they would have gladly continued to make analog scopes if the market and their customer hadn't forced them to make digital ones. Unfortunately that is visible in most of their DSOs, which are average at best and in many cases a pain to use. There's very litte innovation in Tek scopes aside from the price, for which you get slow hardware with an awful UI that was designed by someone who must have hated humans. New scope models often aren't new scope models but simply a re-hash of their older scopes. Support has also taken a steep decline.

The equivalent to Tektronix for digital scopes is LeCroy, which are the ones who really push DSO technology forward and who do a lot of stuff you can't get anywhere else, not even from Keysight.

[Fungus]

Rigol, well, I think the build quality is good. What would concern me more is that they are apparently unable to properly design their hardware (search for 'Project Yaigol').

Summary: Rigol copied/pasted a less-than-ideal design for the main oscillator. It worked well enough that there was no effect on any measurements in the lab... except in one extreme case which took the world a few months to find after launch.

Rigol responded with a firmware patch and the effect vanished. You could replace the 'broken' oscillator with a perfect one and there would be literally no difference at all. Not on screen, not in any measurements.

Do GW-Instek, etc., have similar internal "faults"? We'll probably never know because they don't sell enough units to have armies of people pulling them apart and reverse engineering them.

[Wuerstchenhund]

Rigol, well, I think the build quality is good. What would concern me more is that they are apparently unable to properly design their hardware (search for 'Project Yaigol').

Summary: Rigol copied/pasted a less-than-ideal design for the main oscillator. It worked well enough that there was no effect on any measurements in the lab... except in one extreme case which took the world a few months to find after launch.

Rigol responded with a firmware patch and the effect vanished. You could replace the 'broken' oscillator with a perfect one and there would be literally no difference at all. Not on screen, not in any measurements.

I don't know if that has any effect on any measurements, but copying a design they obviously don't understand it is a very stupid error to make and doesn't exactly instill confidence in Rigol's overall design competence.

On the other side most Rigol gear is reasonably cheap which might compensate for that. But people should make their own mind up as to how much weight they put into the individual properties and issues.

Do GW-Instek, etc., have similar internal "faults"? We'll probably never know because they don't sell enough units to have armies of people pulling them apart and reverse engineering them.

I seriously doubt that GW Instek has made similar mistakes in their design (considering that they make test gear for over 40 years now), and the big brands certainly even less so.

[Fungus]

I don't know if that has any effect on any measurements

You're the one telling people to read the "Yaigol" thread where all this is investigated. Haven't you read it yourself? 

[Wuerstchenhund]

I don't know if that has any effect on any measurements

You're the one telling people to read the "Yaigol" thread where all this is investigated. Haven't you read it yourself? 

I'm telling people to read that so that they have all the facts so they can make a better informed decision.

Since I don't own any Rigol gear any longer I haven't read all of it.

[nctnico]

Come on, this forum is mostly about Rigol and KS. There is a reason why LeCroy is not popular in DIY market, although I do not know what exactly is the reason, maybe price, maybe something else.

Who said this forum is about DIY only? Lots of professionals here who need test equipment to make a living. I'd love to see more reviews of equipment made by other manufacturers than Keysight, Rigol or Siglent because there are many hidden gems to be found which have much better value for money (new or used) or have features lacking on other equipment.

[Wuerstchenhund]

This thread is derailing.

Why?

Why not you start a business selling LeCroy? It will surely make money!

I doubt LeCroy would pay me anywhere near my standard rate. 

Come on, this forum is mostly about Rigol and KS.

Sorry but that it nonsense. There are lots of professionals here as well, probably because there aren't many international EE forums of a similar size. And for a large part its the professionals that give advice and support to the hobbyists in this forum.

There is a reason why LeCroy is not popular in DIY market, although I do not know what exactly is the reason, maybe price, maybe something else.

The reason LeCroy isn't common amongst hobbyists is that for years they pretty much only served the mmid-range and high-end market, which has pretty much their place all along. LeCroy was and still makes the most advanced scopes on the market. You find them in lots of cutting edge areas where any other scope doesn't cut it. Simple as that. On the down-side, they never really cared much about the entry-level (and still only sell rebadges from Iwatsu and Siglent there), so it's no surprise that the average hobbyist doesn't know them. But then, many hobbyists don't even know that there are other companies than HPAK and Tektronix making scopes, so that isn't really saying much.

On the other hand, many professional EEs and scientists know LeCroy scopes, and there's also a sizeable amount of individuals who got one of the older scopes and pretty much got hooked.

So I'm not sure what you wat to say. If you suggest that Rigol and Keysight shall be the only brands ever mentioned in this forum then I doubt that this will work. If you want a Keysight-only forum then Keysight already has one.

In Germany there's a saying: "Fresst Scheisse, Millionen Fliegen koennen nicht irren" ("Eat shit, millions of flies can't be wrong!"). It should tell you that just because everyone follows the mainstream that this is actually the best solution. Sometimes it pays off to consider alternatives.

[Fungus]

In Germany there's a saying: "Fresst Scheisse, Millionen Fliegen koennen nicht irren" ("Eat shit, millions of flies can't be wrong!"). It should tell you that just because everyone follows the mainstream that this is actually the best solution. Sometimes it pays off to consider alternatives.

It exists in English as well.

The point is that the endless Rigol bashing (and pointing people to the "Yaigol" thread is 100% bashing - you know perfectly well that the clock problem doesn't have any measurable effect) is totally out of perspective.

The Rigol DS1054Z has its flaws but:
a) It only costs $400
and
b) You have to pay $1200+ to really get anything better.

Yes, there's a couple of 'scopes around the $800 mark that can do certain things better but you'll lose out badly on bandwidth or number of channels or something else. If you have a very specific need you might be better off with one of those but for an all-round 'scope that beats the (hacked) DS1054Z you need to pay $1200+. Even then it will only beat it on a few features, to really thrash the DS1054Z in all departments with a non-Rigol scope you might need to pay $2000+.

$800-$1000 difference buys an awful lot of other kit if you're spending your own money on test gear. It seems childish to point people to the "Yaigol" thread just because you feel the Rigol is imperfect.

[MotoDog]

I have quite a few scopes.  2 HP, one with LA.  Some older Teks.  Along with HP Function and RF Generators.

And a Rigol Spectrum Analyser.

I just bought a Rigol scope ( the 4 Channel 50 MHz Z Model) on eBay 6 mo ago.  Still have 30 hours of free Options running.

I love it.  Yes, the controls will cause you extra bump or settings, and it does not remember setting when you turn it off.
Tiny Scope, lots of Options and Channels!

Gee, I paid about $360 for it, not used but a few hours.  You can find ways to open options on the internet.

My biggest complaint, is seeing the screen.  There really are more measurement options than I would want.  Start putting them
on the screen and for my old eyes (71), I WISH it had a BIGGER Screen.  Please Rigol make the same thing with a 12-14" display for us old guys!.  Bigger Text on the screen, and a little bigger traces? 

Did I mention, you get 4 Probes with it TOO!  It is running as 100 Mhz now!

I have had and still have one PC Oscilloscope.  I like the hardware and the Price, but the Software was not very good on them.
The Chinese ones for 60$ work good, but I hated the operating software and complete lack of triggering options.
I will never buy another.

The Rigol is actually TOO Small.  Takes no room on my workbench, I keep 2 probes on it at all times hung up on a cup hook to
keep away from the soldering iron stand!

You also can find DISCOUNTS for students!  Check Saileg or others?

Mike

[bitseeker]

I just bought a Rigol scope ( the 4 Channel 50 MHz Z Model) on eBay 6 mo ago.  Still have 30 hours of free Options running.

...

My biggest complaint, is seeing the screen.  There really are more measurement options than I would want.  Start putting them
on the screen and for my old eyes (71), I WISH it had a BIGGER Screen.  Please Rigol make the same thing with a 12-14" display for us old guys!.  Bigger Text on the screen, and a little bigger traces? 

Perhaps give a large Fresnel lens a try. It won't be spectacular, but it'll be larger.

You also can find DISCOUNTS for students!  Check Saileg or others?

And if you're not a student, Saelig and TEquipment have EEVBlog discounts. Search the forum for the appropriate threads.

[Wuerstchenhund]

The point is that the endless Rigol bashing (and pointing people to the "Yaigol" thread is 100% bashing - you know perfectly well that the clock problem doesn't have any measurable effect) is totally out of perspective.

Again, I did not say that the design flaw has any impact on measurements (and no, I don't know that, since again I don't have any Rigol gear any more and I never had a scope, but I do assume it's not a problem in most situations since apparently Rigol has plastered it over through a firmware update). Still, like it or not the design flaw does exists, and I see no reason why people shouldn't be aware of it so they can make their own decision.

I assume you'd prefer that this was kept under the rug, never to be mentioned again?

The Rigol DS1054Z has its flaws but:
a) It only costs $400
and
b) You have to pay $1200+ to really get anything better.

Once again, you're barking up the wrong tree here, as I fully agree that the DS1054z is a great bargain at its price. That isn't the question.

Yes, there's a couple of 'scopes around the $800 mark that can do certain things better but you'll lose out badly on bandwidth or number of channels or something else. If you have a very specific need you might be better off with one of those but for an all-round 'scope that beats the (hacked) DS1054Z you need to pay $1200+. Even then it will only beat it on a few features, to really thrash the DS1054Z in all departments with a non-Rigol scope you might need to pay $2000+.

That is certainly true. However, not everywhere is the lowest possible price the most important factor, and while the DS1054z is good for a lot of basic measurements it's still a very basic scope (like pretty much all Rigols up to the DS6000), and there are many tasks where that isn't enough. The question is if what the OP wants to do can be achieved with a cheap Rigol, but so far I don't think we have enough details to say for sure. Robotics is a huge field and not just limited to motors, actuators and power controllers so until here everything is more or less guesswork.

It seems childish to point people to the "Yaigol" thread just because you feel the Rigol is imperfect.

That isn't a slight imperfection, it's a pretty big mess-up from a design perspective. Now you might not care how your test gear works but many professionals do. And then it doesn't really matter that the problem has been plastered over by firmware or that the scope is cheap, if they can't even design an oscillator properly then I really have zero trust in that instrument. I accept that for many hobbyists that isn't an issue, but as I said people should make up their own mind and for that they need all information, not just the positives.

The real question is why you're so keen to suppress the existence of the Yaigol thread?

[tautech]

It seems childish to point people to the "Yaigol" thread just because you feel the Rigol is imperfect.

That isn't a slight imperfection, it's a pretty big mess-up from a design perspective. Now you might not care how your test gear works but many professionals do. And then it doesn't really matter that the problem has been plastered over by firmware or that the scope is cheap, if they can't even design an oscillator properly then I really have zero trust in that instrument. I accept that for many hobbyists that isn't an issue, but as I said people should make up their own mind and for that they need all information, not just the positives.

The real question is why you're so keen to suppress the existence of the Yaigol thread?

Because there's so much more in there that some don't want to get out. 
https://www.eevblog.com/forum/projects/project-yaigol-fixing-rigol-scope-design-problems/msg890964/#msg890964
From the attached PDF:

In DS2000 oscilloscope not only the PLL power regulator oscillates, all 1117 type LDO voltage regulators
oscillate in factory scopes.

I don't know if that has any effect on any measurements

You're the one telling people to read the "Yaigol" thread where all this is investigated. Haven't you read it yourself? 

I'm telling people to read that so that they have all the facts so they can make a better informed decision.

Since I don't own any Rigol gear any longer I haven't read all of it.

You should.
The crux of it all is in Bud's first few posts and particularly the attachments.
Bud's work will never be dismissed IMHO as he and MarkL initially bought the PLL issue to this forums attention, Dave then did a vid on this F***úp and pressure was then bought on Rigol to place a bandaid over the problem.

History that can't be overlooked as much as some might want you too.

[JPortici]

Did I mention, you get 4 Probes with it TOO!  It is running as 100 Mhz now!

True, at the end of the day 400 for a set of okay probes is a good bargain, i like 'em
(really)

[Karel]

History that can't be overlooked as much as some might want you too.

Like this for example?

Don't buy anything from Siglent if you are not sure you don't want to sell it on Ebay later...

https://www.eevblog.com/forum/testgear/siglent-they-filed-a-'wrongful-trademark-claim'/

[tautech]

History that can't be overlooked as much as some might want you too.

Like this for example?

Don't buy anything from Siglent if you are not sure you don't want to sell it on Ebay later...

https://www.eevblog.com/forum/testgear/siglent-they-filed-a-'wrongful-trademark-claim'/

I knew casting a sprat would catch a mackerel.

Have we seen any Rigol HW revisions that might indicate all these design issues might have been addressed ?
Have we seen any representation from Rigol in Dave's lab explaining they have?
Have we seen Rigol involved in open discussion giving reasons for their design errors and steps taken to ensure they won't be repeated ?

The Siglent issue you raise Karel has been fully and openly addressed on this forum all the way to the CEO of Siglent and it is surely a pity that Rigol are not also so open so that their matters can be put to past history too.

[eeguy]

Thank you for the comments. Most likely I go for either GW Instek or Keysight. Are they quiet? I cannot stand noisy equipment. Can they also be hacked with software enabled freely and easily to get more functions and higher specs without the company knowing? In the case of GDS, some scopes have an 'A' ending while others have an 'E' ending. For example, 2204A vs. 2204E. 2204E seems to have 10M/ch of recording length while the 2204A only seem to have 2M/ch. 2204E is also less expensive. I asked GW Instek via chat but no reply even chat is online.

The 2104A has a rise time of 3.5ns while the 2204A, 2204E and 2304A has a rise time of 1.17ns. In general, is 3.5ns fast enough?

For GDS, I consider 2102A, 2104A, 2204A and 2204E. Cannot find GDS-2000E on their website. Which is the latest and greatest? I need external trigger function (e.g. press a button and different devices start working) and usb storage of data for plotting in EXCEL or Matlab. Experiments last about 10-30 seconds, no more than a minute or two.

[Fungus]

Thank you for the comments. Most likely I go for either GW Instek or Keysight. Can they also be hacked with software enabled freely and easily to get more functions and higher specs without the company knowing?

No.