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A much needed update:


The demobot was able tp prove, that under manual control, and lots of finagling, the competition can be completed. If needed, I could spend another month making it truly autonomous, but hopefully I won't have to do that. If anyone wants to watch some vids, here's where they currently exist.


I'm shifting focus back to the PCB, because I really want to test out v2. There are, of course, some more changes coming, but I'm really excited about them!

  • I mirrored the top half of the PCB, such that the XBee is on the left instead of the right. This'll make routing a bit easier.
  • I'm switching out pretty much all of the regulators The 5v regulator was too safe, such that it couldn't actually power the servos. Oh well. I found one that can.
  • I've also changed the 3.3v regulator to be powered off of the entire input voltage range, such that the new 6v, 5A regulator can be just for the servos.
  • I have a tiny LDO going into the VBUS line on the launchpad for the LEDs.
  • Adding a chip to easier select UART0/1 for XBee/Bluetooth
  • Adding headers directly under UART0 pins on the Launchpad, in the hopes that I can write a wireless bootloader!

In other news, I won't have a free weekend until the end of November!

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Pictures? Pictures! Pictures. https://plus.google.com/117104116706660321116/posts/Zp5z1x4UBAh       (Yes, I'm to lazy to upload them to the forum...)    

Great project.  I was looking at power supply solutions last night.  Primarily I wanted a really simple 3.3V source for my CPU etc. derived from a high amp 12V power supply which would drive my LEDs,

Wow, I had forgotten about this post.   So a few updates: First PCB:Very little worked. The 5v regulator worked once or twice, but due to bad reflowing it didn't ever work again. The 3.3v Regulat

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Great project.  I was looking at power supply solutions last night.  Primarily I wanted a really simple 3.3V source for my CPU etc. derived from a high amp 12V power supply which would drive my LEDs, motors etc.  Normal LDOs get mighty hot when driven from 12V.  I looked at the switchers and didn't like having to add an inductor and several caps and resistors.  Then I discovered these drop in DC/DC converters for a reasonable price.  I ordered some to play with.


R-78E3.3-0.5 for $2.84



OKI-78SR-3.3/1.5-W36-C kind of expensive at $4.30 but no additional parts at all



I like your idea of using TI samples, but just wondering if you where aware of these parts and what you think of the idea of using them in this sort of situation?  Generally I only need high current 12V and low current 3.3V so 5V is not needed. 

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@, I was actually not aware of parts like those, but for a different reason than you might think.


Whenever I work on a project, I like to push myself to try new things. Right now, I'm really into SMD, and even have plans to start messing with BGAs and a PnP Machine in the works to help me do even more! It's because of this that I now avoid Through Hole parts like the plague. I'm always concerned about size and efficiency (my full time job involves low power microcontrollers in the Internet of Things market), and I've found that SMD parts overall are just better overall about size and efficiency.


Also, in regards to TI, I'm definitely aware of other suppliers, but truth is, I don't like messing with power if I don't have to. TI has a tool called WEBENCH Designer in which I tell it what power restrictions I want (input volage, output voltage, efficiency, cost, footprint, etc...), and out comes a list of possible ICs, along with the exact part that I need to source. SO much easier than it use to be, and quicker.

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Good rationale for sure.  It's funny, I am always trying new things too, but usually because I wing it (i.e. do little research and assume I am good to go) and discover new edge cases where my ideas don't work as planned.  In this case, I discovered that over-stressed LDOs burn like hell.  At first I thought I had a short or something, then thought about it and realized that the LDO would have to dissipate a ton of heat, hence the need for a quick solution for an existing circuit.


As for SMD, I agree too.  I just got a little CNC mill and plan to etch PCBs as soon as I am set up and calibrated etc.  I can't wait to see the PnP.  I am sure you'll post that too? 

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A brief update. Routing is still in progress (~70% completed imo). I'd like to get it completed before this upcoming week ends, but only time will tell on that.


@Igm, I'll definitely be posting that somewhere, but most likely not here. Ill probably post it in the Beagle-Fu community since the current plan is to drive it using a BeBoPr cape and BeagleBone Black. However, if I end up using a Tiva Launchpad in the project (I have an idea for ~$5 feeders that involves some creative embedded systems), I'll cross post it here as well :)


Currently aiming to have the mechanics of the machine completed by the end of the year (I like volunteering way too much...)

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  • 3 weeks later...

Woo! Happy Thanksgiving weekend everyone!


I wanted to post another update, as things are coming along quite nicely.

On v2 of the PCB:

  • Routing was long since completed, and the PCB is actually already back and in my hands! OSHPark turnaround times are getting better and better!
  • I have an updated BoM located here. In really low quantities, the components total to ~$65, not including parts Mouser didn't carry (Samtec headers, Inductors, and IMU) and XBee module. The interesting thing is that at 100 boards, the price drops to ~$40 (without Bluetooth, it drops to ~$30).
  • I'll be laser cutting the stencil this weekend and if all goes well (aka parts get in on time and Reflow Oven still works), I'll have a prototype by the middle of next week.


On the PnP:

  • I have most of the hardware in and will be working to get most of the mechanics built by the end of the weekend.
  • I think I've figured out a cheap way to make Cut Tape feeders, such that each one costs ~$7 each to make, before bulk savings.
  • Aiming to have all hardware for the PnP complete by the end of the year.
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  • 2 months later...

Whelp, I think I'm about due for an update...


Robotics BP v2:

  • Nothing blew up!
  • The 1st board isn't completely assembled (had to take off ICs to track down a short).
  • Amusingly enough, I'll be needing this board to test the Pick and Place (testing out Servo-cased actuation instead of Stepper driven).



  • I'm on v4 of the CNC hardware now (four iterations in two months isn't too bad, imo).
  • Latest version:
    • ~16" cube
    • Steel tube frame with Aluminum inserts
    • Aluminum mounting blocks for Rods & steppers
    • Core XY motion
    • PTFE gantry and carriage blocks (currently testing)
  • Focused on getting the HW completed since after this weekend and next, I'll be completely booked until the end of March...
  • BBB + Azteeg x3 + Octoprint works wonderfully! Internet-controlled PnP, here I come!


Also, I would suggest keeping an eye out on my website (anomalousmaker.com) since I want to start using it more ( anything > nothing).



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Brief update before I switch to CAD for the PnP and another project (Firmware in Linux, CAD in Windows).

I've completed some testing w/ the BoosterPack, and here's what I've found:

  • Holy crap did the regulator change help! I connected 5 servos and drove them all at once, keeping an eye on the servo's supply voltage, and that thing was SOLID! The only oscillations that I was able to observe were those of the Multimeter.
  • That being said, I had some weird Mosfet issue with the Mosfet I was trying to use to enable/disable the power supply of the Servos. Removed it for the time being.
  • The solenoid circuit still works, with the caveat that I need a pullup resistor for pin 0 of the IO Expander.
  • Only two of the four motors work atm, but this is because I changed the pin mappings to the devices due to the Tiva parts having a hardware QEI peripheral. I'll need to update the software to use the hardware QEI and switch to PWM outputs for the Servos and Motors instead of what I have now.
  • All I2C devices are alive as well!

Oh, and one more semi-related thing. As a proof-of-concept, I managed to reprogram a Launchpad connected to a BBB over the internet! The next step is to get a USB Hub and WiFi USB Adapter, and throw that all together to get rid of Ethernet. The final step of course is to cut the tether and run the entire thing off of batteries and have a completely wireless, very robot-friendly set of dev boards :)

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  • 3 weeks later...

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