I am extremely excited to share a project that has been in the works for some time: this is the Stealthboard powered by Smoothieware
The board has four integrated Trinamic 2208 stepper drivers with full digital current control. There are also two high power mosfets and a number of other peripherals. Tried to keep it as compact as possible at 100x60mm, and all with 32 bits at 120MHz power.
This is still a work in progress and as you can see, has been beat on!
Would love to know what everyone thinks about it! More info to come soon.
Fellow mods if you feel this is not appropriate just let me know and I will remove the post.
The stepping features on the 2208 are interesting. Have you been able to test them? Up to 256 microsteps? Usable torque? Also saw quiet modes. Are those effective? Usable with the custom microstepper modes? No heatsink needed on drivers? Just relying on copper plate?
Are you looking to sell these down the road? Any idea of target price?
Edit: wow 2208 has a uart too. Is that wired to the uC?
@Greg_Copeland the 2208’s are in my opinion the best blend of size and features. The video shows just a quick test of them although I will be testing them extensively coming up very soon. I also have a number of initial beta testers lined up who will be getting these first version boards. The drivers do interpolate to 256 microsteps which contributes to how silent they are. Unlike the Stealthchop mode in the TMC 2100 drivers, the torque output is useable, as the board makes the use of the new and improved Stealthchop 2. The board comes without the UART hooked up right now as we have not yet been able to change the configuration through that, but Stealthchop 2 in my opinon works with enough torque to be a good option (more official tests and numbers coming soon). The board is 2oz 4 layer copper throughout which sinks the heat quite well. So far no need for heatsinks or fans. This is one great feature over using the stepsticks as with integrated drivers, the sink is significantly larger in a sense.
The board does support the GLCD which uses a small expansion board that goes atop the male header shown (this adapter board will be pictured soon. It also supports the Panucatt Viki display. Next to that is an Ethernet breakout if you are interested in using smoothie’s built in Ethernet.
These will indeed be for sale coming down the road soon. I am aiming for a price of $99- definitely not more.
@peter_rowser yes! I am working on a 5 driver version as well. It will also most likely have expansion past 5 drivers for the power users.
@Rien_Stouten I have my testers for rev 1 here lined up, however if you are interested, I can get you lined up for the next revision.
I think it’s even more similar to my Cohesion3D Mini than the Azteeg one. Pop out the stepstick sockets, drop some TMC2208’s and voila. I have to say these drivers are awesome though.
@Greg_Copeland the 2208’s are my favorite for all around size an performance. They do indeed have 256 microstepping interpolation and usable torque. The major advantage of the 2208’s is the Stealthchop 2 mode, which is quiet like TMC2100’s but has a significantly higher torque output when compared to the original Stealthchop 1. This is the mode that is shown in the video. They are not audible nor have a stepper whine at 12V like the 21XX tend to.
Because they are integrated into the PCB, the heat spread is much more favorable when compared to stepsticks. Further testing is needed for hard numbers, but initial tests suggest that at reasonable current levels of 1A or less, they will work fine as shown above.
As for if I am going to sell these- Absolutely! Ideal target price is $99 and it looks like that is completely doable.
UART is not wired up as of now, however microstepping can be configured via jumpers on the underside.
@peter_rowser Absolutely. Working on a 5+ driver version with expandable driver space as well. Still in development though.
@Rien_Stouten I currently have a few individuals that will be getting these first runs, but I can definitely put you on the list for in the near future! Email me if interested- griffin(at)letsprintthat(dot)com
@Blake_Dunham the two boards are similar, and as Ray pointed out it is somewhat similar to the Cohesion3D mini as well. The most significant difference is the onboard drivers. By integrating them, the thermal properties are much better as you have a larger pad close by to sink to. Trinamic drivers tend to run quite hot and often require a fan to cool them. Our aim was to keep them integrated and thus cooler. The pricepoint is also a significant difference as we aim to have these for sale at $99, making it less than the X5 mini before drivers.
If you don’t mind the hopefully constructive criticism, I do agree with @peter_rowser that you should look to add another driver on the board; potentially even allowing cloning. This allows for x, y, zz, e, and x, y, z, e, e setups. This combined with higher amp (1.5A) would make it a fairly universal board.
It looks like they can safely drive 1.5A, but I assume that requires some heat sinks. The datasheet looks like it only requires some resistor changes for the drivers.
Possible? Completely blow target price? Simply not desired?
At any rate, great job on the board. Thanks for sharing your project.
@Greg_Copeland no I absolutely appreciate the criticism! That’s what I posted it for. My target was to do a smaller version for people who don’t need a ton of features, and also don’t have a big budget. That’s what is pictured here.
There will indeed be a 5+driver version that is more dedicated towards the power user. Making it universal like you said is the goal:-) really appreciate the feedback!
@Griffin_Paquette That’s actually part of what I suggest the extra drivers. If you’re willing to slow boat something, for $75 you can get a smoothie compatible board (mks sbase 1.3) and touchscreen display - delivered. It has heat sinks, x, y, z, e, e, and 3.3/5.0v power on board, endstops, 2xtemps (iirc), and open gpio ports. Granted you definitely have nicer drivers (vs 8825).
If you’re going for the budget crowd, you’re asking them to pay more for “less.” I put less in quotes because…dang, those are some nice drivers you got. But that also raises the question, are those drivers alone worth a ~$40 premium to frugal buyers? While I’m sure the answer is yes to many shoppers (especially to those who won’t slow boat), will that satiate your desired market share; or a subset thereof? Plus, at the $100 mark, IIRC, some of the other smoothie board players are now on the table. Meaning, perhaps there is more competition than you already believe(1).
From a market sense, wouldn’t you want to try to tap the broadest possible market without artificially cutting off part of that market?
(1) Given you’re a moderator here I’m assuming nothing I’m saying is actually news to you. But perhaps you’ve not thought of it positioned as I have.
that does look like a nice board!