Duet hardware actually makes it into Thomas Salanderer's videos

Mysta

@vlad said in Duet hardware actually makes it into Thomas Salanderer's videos:

@bot Yeah, but I paid around $120 for Duet, and Maestro is a "budget" version for $130? I am missing something? $:-\$

You got a Duet Wifi/Ethernet(2) for 120?

Vlad

@mysta just double checked. It was $160... Well, in my opinion anyone who is already throwing $130 into the board wouldn't mind throwing additional $30 for a slight upgrade and possibility to expand the system in future. $130 is still very expensive. MKS makes good budget boards for $40-$60, even 32bit, if someone wants real budget. Neither $130 nor $160 is any close to budget ptice for this. Just saying

dc42

A genuine Einsy Rambo board is $120 on Ultimachine's web site, and it has only 4 stepper drivers, an 8-bit processor and no web interface. So I think $130 is in the right ball park for a high-quality board that comes with support and a warranty. In time I expect the price will come down.

MKS can only sell boards as cheaply as they do by parasitising open source designs, violating the open source license agreements, offering no support and little or no warranty, and selling boards before they have got the design right (as happened with the SBase). We're not like that.

SuperJETT

@dc42 said in Duet hardware actually makes it into Thomas Salanderer's videos:

We're not like that.

Exactly, keep up the great work.

It's always better to be a leader than a follower.

A Former User

If you listen carefully to the video, you can hear Arthur Wolf sobbing in the background

OG3D

@dc42
Is implementing closed loop support in hardware and software by an encoders on your radar for next version of duet?

dc42

@og3d said in Duet hardware actually makes it into Thomas Salanderer's videos:

@dc42
Is implementing closed loop support in hardware and software by an encoders on your radar for next version of duet?

We've been keeping an eye on developments in this area, with a view to doing an alternative DueX expansion board that would drive BLDC motors instead of stepper motors. The main problem so far is the lack of suitable inexpensive BLDC motors. The cheap ones used in quadcopters have no gearbox and no sensors, which is OK when you only run the motors at high speeds, but no good for 3D printers. When we need is a BLDC motor with built-in commutation sensors (so that we can run the motor at low speeds), a reduction gearbox (because BLDCs are only efficient at high speeds), and that gearbox must either have very low backlash or else we also need an encoder on the output shaft with a resolution of at least 5000 counts/rev.

WILD9

Looks like the partner company has jumped the gun on the announcement, they have a page up with all the details already. I wont link to it but its not hard to find on google.

dc42

I presume you mean https://store.printm3d.com/products/duet-2-maestro.

The stepper motor current figure isn't quite right: the maximum is 1.6A peak but we may limit it in firmware to a lower value when we've done the thermal tests. The 18A bed heater current rating also has to be confirmed. The 12864 LCD isn't supported in firmware yet, but the hardware interface has been proven.

kingfisher

The news has also reached Reddit.
Do you have any idea of the UK price yet?

WILD9

@dc42 yes that's the one, didn't really want to step on your toes so didn't put the link up.

The board looks looks great though, I was struggling to justify the cost of a Duet WiFi for my lowly CR-10 but this looks perfect, cant wait to see the the rest of the details, price etc.

dc42

The reddit thread is here https://www.reddit.com/r/3Dprinting/comments/8dbirp/details_on_the_newest_duet_board_that_thomas/.

Mysta

@dc42 Is it mentioned if the Maestro will support RTOS?

JRDM

What I'm seeing on the Maestro looks pretty good. If anything, I think the preorder price will add a lot of new people to the Duet platform. Hopefully the retail box price can go down

The interview mentioned fuses on the Duet 2's thermistors. I go to the latest schematics on Github (Duet 2 v1.03) and I don't see any fuses on the thermistor circuitry. I see some resistors and small caps but no fuses.

Then there was talk about protection circuitry to protect against motor disconnections, and the closest I see is 1nf caps on the motor connectors. I would have expected to see a gaggle flyback diodes for driver protection. Trinamic data sheets don't seem to mention flyback diodes or even show them built into their motor output FETs.

Am I missing anything?

dc42

@mysta, I am already running a RTOS build of RRF on a Duet Maestro in one of my printers. The SAM4S8C on the Maestro has the same amount of flash memory and RAM as the SAM4E8E on the Duet WiFi/Ethernet, so the RTOS build will become the standard firmware for it.

@JRDM, there is a PTC fuse between VSSA and ground. The driver protection comprises the 1nF caps along with careful PCB layout, to limit the dV/dT seen by the mosfets and hence avoid parasitic turn-on. My testing has shown this to be adequate, see https://www.youtube.com/watch?v=uyWolKFzb-A. All stepper motor drivers include flyback diodes.

JRDM

@dc42 OK well Trinamic's data sheets don't mention it or show it in any of the circuit diagrams. I know Allegro shows them in their circuit diagrams but doesn't mention them.

But setting that aside, what are you doing on the drivers that works so well? The video is impressive.

BenDiesel

hey you might take a look at what thease guys are doing for the bldc with encoder
https://odriverobotics.com/#odrive

OG3D

@dc42 said in Duet hardware actually makes it into Thomas Salanderer's videos:

@og3d said in Duet hardware actually makes it into Thomas Salanderer's videos:

@dc42
Is implementing closed loop support in hardware and software by an encoders on your radar for next version of duet?

We've been keeping an eye on developments in this area, with a view to doing an alternative DueX expansion board that would drive BLDC motors instead of stepper motors. The main problem so far is the lack of suitable inexpensive BLDC motors. The cheap ones used in quadcopters have no gearbox and no sensors, which is OK when you only run the motors at high speeds, but no good for 3D printers. When we need is a BLDC motor with built-in commutation sensors (so that we can run the motor at low speeds), a reduction gearbox (because BLDCs are only efficient at high speeds), and that gearbox must either have very low backlash or else we also need an encoder on the output shaft with a resolution of at least 5000 counts/rev.

@dc42
What do you think about them?
https://hackaday.io/project/11583-odrive-high-performance-motor-control

I was more think of adding support for encoders.
Something like this one.
https://www.cui.com/product/product-resources/amt100-series-modular-encoders.pdf

dc42

@og3d said in Duet hardware actually makes it into Thomas Salanderer's videos:

@dc42
What do you think about them?
https://hackaday.io/project/11583-odrive-high-performance-motor-control

It looks good, but way overpowered and too expensive for ordinary 3D printers. It might be good if you wanted to print a house though!

T3P3Tony

@vlad said in Duet hardware actually makes it into Thomas Salanderer's videos:

Oh well, that's not a review unfortunately. But still nice to hear some news. Hoping he will actually review the board. Maybe he didn't review it because Duet3D folks did not offer him a board? Could be a reason.

We have offered him a board but Tom has a lot on right now!