Showing posts with label Mini1. Show all posts
Showing posts with label Mini1. Show all posts

Sunday, September 13, 2020

Current Thinking in the Robot Labs

These are things currently being thought about at the TENRA Robot Labs...

Late nights and early mornings in the lab!

3D Printing

Ah... the beauty of 3D printing for robots!   It is the magic of having an idea in your head, which leads to, a sketch on paper, a drawing in CAD, and then a solid print - or many prints:


1st - A quick sketch on paper

2nd - A quick draft in OpenSCAD

3rd - a quick print - a solid Object!

Finally - Repeat as needed

I really love this aspect of Rapid Prototyping. I find it one of the more enjoyable steps in robot building. At each step in the process, you can find opportunities or issues with your design. It is fantastically easy to go back a step or two and add improvement to the design.

A good example is in this very simple build of "Node", pictured above.  "The Node" is an experiment in the Milli Project. I wanted to explore the ability to move in two directions on the helix in order to improve the mobility of the millipede robot. 

At each step in the process, I found that new aspects of the build became evident.  Even in the first print, i realized that I need more of the 'feet' to touch the printer bed. A quick change to parameters in the CAD, and it solved the problem. Finally, a quick print of three copies of the nodes. I assembled them and was able to perform my tests. The result was that the solution would not work as is due to certain bindings. I was having a difficult time imagining this complex relation in my head.  The rapid development of the concept provides a fast path to success or failure, both are acceptable!


Min1 - what should it do at night? 

Min1 is the Minimal Viable Robot for the Totally Not Evil Robot Army.  But, I am just thinking, what can this robot do at night.  It is just sitting around, with nothing to do.  Idle cycles are the devil's playground, right? So perhaps it needs a few teeth and a sensor to seek things (like ankles) out and make stabby motions.  ;)

Min1 - outfitted with ultrasonic sensors and stabby teeth


Min1 ready to Roam - seek and stab


Min1 Robot - as a Franken-prototype ready to go

Tilt!

Tilt, the balancing - 2 wheel Robot, is sitting prominently in the TENRA Robot Labs. It is patiently waiting a more powerful power source.  Twelve Volts DC is not going to cut it, it needs more power to keep the recycled printer motors from stalling.  I have just recycled a 19V power adapter that I will use as 'shore power' for the next round of testing. 

I am really liking Tilts new 'eyes'!




Saturday, July 11, 2020

Minions!

A Dream of Totally-Not-Evil-Robot-Army Minions!!


Minions - and not the D'zney ones!  Every Mad Scientist needs them.  Especially if you are going to build a robot army. Minions can be the foundation for any robot army, the very lowest of the 'foot soldiers'. What would be the robot equivalent?  Perhaps the most simplest robot configuration. In 'Agile' speak: the Minimal Viable Robot?

Robotic Minion with a Manipulator Arm

The Minimal Viable Robot, would have the minimal number of parts, and be the easiest to replicate. It could be small, one would say Miniature. A minimal, miniature robot - the first one in the Robot Army.  It will be a Min-i-on, and mini-one, a Mini1!

Lets build it!!  Because this Robot Army needs many many more robots!  It needs Mini1s!!

Mini1 sketches

Design


What is the bare-bones, minimalist robot, that still has some kick?  I would propose:

  • 2 Wheels
  • 2 Small Motors
  • a Motor Controller
  • Microcontroller
  • and a Battery

That sounds really basic. but, if it is going to do something - like to serve butter - in needs at least a sensor and a manipulator.

Here are some parts I have laying around the Totally Not Evil Robot Army Lab. This is a really cheap build with these parts. The Wheels are from an old printer. The motors came off of a chotsky fan I collected from a trade fair. The motor driver is a little overkill L298N but will do the job. The microcontroller is a Arduino Pro Mini (clone) about $5. and for power perhaps this battery bank battery 5V.  For a sensor, I have a common ultrasonic ranger HC-SR04.  And if I go for an arm, I will use simple micro-servos. In the bottom corner is a ESP32, which would be more powerful, and provide wifi/bluetooth - perhaps for future versions.

Potential Parts for a Mini1 - Robot Minion


Alright!  Let's get started:

Mini1 - first CAD sketch - OpenSCAD