Arduino robot adventures (1)
============================

I have  started -  for practical reasons  of course -  to play  with an
Arduino-based 3D-printed robot.  I decided to use the SMARS  [1], It is
not "free hardware"  but it's freely available for personal  use and it
is rather simple to print and assemble.

I have  had a few Arduino  [2] parts at  home (the Arduino Uno  an some
add-ons) and the rest was quite inexpensive and easy to obtain.

The reason why  I have wanted to  get this thing was a  need to inspect
some hard  to access places  in our cottage  and to rescue  things from
those places. A robot with camera would be useful here.

I have  got then Prusa [3]  Mini printer earlier this  year and finally
make it  work in summer.  The Prusa  is a local  business so it  was an
obvious option.

The SMARS  is small enough to  be printable on this  machine. It needed
some 10 or so hours (the chassis, some small parts, tracks and wheels).
For the  begining I decided  to made a Bluetooth-controlled  machine (I
have had  to use an Android  device to control it  - it is going  to be
replaced by a dedicated Andruino-based controller). I have installed an
ESP32-based camera on the device.

Surprisingly, all of  that worked. I spent a lot  of time when figuring
how  to power  the ESP32  thing (it  is fully  independent on  the main
Arduino-based control system, I even have  had to use a dedicated power
source for it).

In practice  I have  to use  2 devices  to control  a single  robot: an
Android tablet for control application  and Wifi-enabled device for see
the camera  image from  the ESP32.  This cannot be  done with  a single
device as the remote control app  does not support divided screen mode.
Obviously, there is a room for improvements.

The  machine  have   been  used:  it  has   been  inspecting  otherwise
inaccessible places  for lost  items, controls mouse  traps and  so on.
There are some issues  - the original tracks are not  ideal (I am going
to print  different ones)  and it  can travel less  than 10  m on  a 9V
battery (I of course use rechargeable ones). To replace the battery the
machine must be disassembled so I have printed a modified case with the
doors in the bottom.  Now I am testing a second one -  it is planned to
use this machine to actually  rescue things found by the camera-enabled
one.

The software side is slightly tricky -  I have had some issues with the
Arduino IDE  shipped with  my ppc64le  Fedora (it  seems that  it's too
old). So I  use the MNT reform  with the current Debian on  the ARM for
the Arduino IDE. The OpenSCAD  (used for deign of customised additions)
and the Prusa Slicer are OK in the Fedora so I'm able to use them on my
fastest machine (the Raptor Engineering Blackbird).

A lot of fun with so tiny device!


References:

[1] https://www.thingiverse.com/thing:2662828
[2] https://arduino.cc
[3] https://prusa3d.com