Saturday, August 10, 2019

Sabbatical Almost Over

Hi all, 

I will be shortly returning from a break.  It has been a busy summer with travel, a new company, a move to the city, and more.

I am setting my Totally Not Evil Robot Army Labs, it will be returning shortly. 

I have also noticed that my blog has been 'picked up' by Ukrainian Search Engine Optimization groups (nefarious or not?). Most of the blogs are coming from random and not so random sites mostly in the Ukraine and Russia.  Welcome I guess?

In the meanwhile, if you are in Europe in October, the next annual Toulouse Robot Race being held.  I do not believe I will make it this year! :(

bis bald!

Monday, May 27, 2019

One Year Anniversary

The Totally Not Evil Robot Army Blog is 1 years old today! (May 27th, 2019)

It has been really nice building robots and writing about it.  I fully plan on continue.

Here are some statistics from the first year:

4 Robots - Mojo - Robot Dog, The Bug, The Wild Weasel, and Centi:

43 Posts

3523 - page hits:
  • 1337 from Israel - due to two massive single hit page crawlers that hit for 600+ and 700+ hits each - robots searching robots I guess?  :)
  • 641 page views from Germany - Where the blog is located.
  • 1545 from the rest of the world.
A few spammers commenting on the blog, trying to place SEO links. - which were mercilessly deleted by the way.

Most references come from, I only recently fixed my links from my YouTube Channel.  And special shout out to Norbert Heinz at for the referrals.

The next year will be in a new "smaller" location for me, and a little added challenge of trying to start a business at the same time. (many of my new robots are virtual, but have ML and AI! ;)

I am looking forward to the next year!
Düsseldorf Doug

Monday, April 22, 2019

Centi (#5) - New Leg Design is Printed


Here is the latest print and video of the Centipede Project.

moving from OpenSCAD to print went fairly smoothly.  As you can see, I have enclosed the main rotating mechanism that moves the chopstick legs.  In this design in OpenSCAD, I have rotated everything along the Z axis, to make it easier to keep centered. The covering socket cap and ball all align, as well as the cam. You can also see holes along the structure, so that small screws can be used to assemble the leg segment. I am reusing screws from recycled printers that are used to bind plastic parts together.

OpenSCAD design
At the 'base' of the leg, I have created a hexagon. This seems to me to be 'self-bio-inspired'. I have not used hexagons in previous designs, so it is novel to me. More importantly, it fits the nature of the leg, as there is no specific 'down' or 'up.  One the walls of the cam base, I have added two small holes for M3 bolts. This allows me to connect two or more legs in sequence... thus forming the multiple legs of the Centipede.

New Print
At this time there are only two leg segments connected.  The M3 bolts are not visible, as they are inside the cam housing.  Note: I had a near-fail as I forgot to leave clearance between the cam housing wall and the bearing mount.  There are many issues to design out when doing project like this. This is why physically making the prototypes is very important to realize assembly issues.

New Gears to connect to Drive
At the base of the Cam Housing are two gears attached to the cam itself. The cam shaft runs through a bearing and then is connected to the gears.  The gears are "kegelrad" from the OpenSCAD library "Getriebe Bilbiothek für OpenSCAD".  The kegelrad could give me an ability to mount the drive gears at an angle different from the cam housing.  We shall see!  ;)

Saturday, April 13, 2019

Centi (#4) - Design Video


I have published a video of the initial design and 3D Printed "drafts" of the Centipede leg mechanism.  You can find the video below on my YouTube channel.

From a design perspective, the drafts have served their purpose. It is now a good time to take what we have learned and start a new draft.  

I like the concept of making each leg of the Centipede to be a "module" that can be replicated and connected together.  I am also realizing that I don't care much for the 'rectangular' frame that was in the drafts.  The legs may need to be moved around.  Honestly, the rectangles do not seem to match the aesthetic of an bio-inspired robot.

Here is my new concept that I am working on ...

Centi - a new aesthetic! - CAD in OpenSCAD

Saturday, April 6, 2019

Wild Weasel - Tracked Robot (#3)

I have just posted a YouTube Video of the assembly of the Wild Weasel track.  You can find it here:

Wild Weasel a completely 3D printed Tracked Robot.  I wanted to build a tracked robot, due to their stability, and at the same time use some motors that I had recovered from recycled printers.

The project went very smoothly, a lot of CAD work was need to design the treads, chassis, and gears used.  The robot uses a Raspberry Pi and an L298N motor driver. This was my first time to use a Tallent Cell power bank, which provides 12V and 5V power - great for RPI and the motors.