Posted in Buyer beware! on January 29, 2018 by asteriondaedalus

Have poor eyes nowadaze.  So I have a few gadgets to help out.  I have a large plastic fresnel lens, a jeweler’s monocle, a hands free mag glass with light, namely:

Most have limitations and I am happy enough that they work within those limitations.

Still, I was looking forward to my USB Microscope.  Only $20 etc. so not expecting much but frack me!

The one that turned up seemed fine.  However, I was dazzled somewhat by the brightness of the LED.  There is an adjustment but, via the viewport, you have pitch black or you flood the viewing field.

The software that comes with it installs BUT the purposed software for the microscope (that includes allowing changing of resolution) installs but does not run on Windoze.  There is a second piece of software (AmCap) that I suspect is a open source program.  It runs fine but does not offer any more functionality than the camera app that comes with Windows 10.  Turns out good old MyCam works a treat with the resolution setting so you don’t need to install anything from the vendor disk.

Functions okay.  Lighting problem disappointing.  I am only using it for fine PCB work anyway so likely not a problem, and it was only $20.

View flooded by bright LED array supplied inbuilt

Using a warm, slimline, LED desk lamp


I need some discipline

Posted in Uncategorized on January 23, 2018 by asteriondaedalus

While poking around on the Net I found fuzzyclips (again). It is old so needed Borland C to compile. Luckily I had a linux gadget up and running. So with a little work to find buile dependencies I got it running on the C.H.I.P!

So yes, I have gone back to play with Jess and FuzzyJ.

Gag! Need a 12volt BEC as well

Posted in Home Made Lidar on January 18, 2018 by asteriondaedalus

So, for the final prototype I will likely need a 12volt BEC to drive the gimbal board – though I won’t need that for the bench.  What I am missing is an adjustable bench supply.  Still something that should have on my bench.  So, off to Jaycar on weekend.

Otherwise, here are the basic innards of the home made lidar.  The bore on the gimbal is not wide enough for the slip ring body, but that is not a problem – it will be accommodated by the way I mount the slip ring.


As for the Benewake TFmini Micro Lidar, I think I might play with a 3D print for the final prototype.  My geek sister has a 3D printer and I am most of the way through an online Blender course (specifically so I can fall into 3D printing design).  Otherwise, a short piece of aluminum angle should do.


Just for posterity the physical specs for the gimbal motor are:

Poles: 12N14P
Resistance: 10.0 omh
Weight: 41.42g
Wire: 0.19mm
Turn: 100T
Bottom holes center to center: 16mm and 19mm
Top holes center to center: 16mm (vendor website says 12mm in on place and 16mm in another).


Physical specs for the lidar are:



Posted in Home Made Lidar, The after market on January 3, 2018 by asteriondaedalus

So, mislaid the cable from my Benewake TFmini Micro Lidar.   What on earth is this socket type please?  Anyone?


I pinged 3XDR, from where I got the gadget, for a hint as to the connector type. He is kindly sending me one!  Otherwise, it’s a JST-GH 4-pin.  Used in pixhawk.


All good.  New cable on hand. I have the gimbal board too, and a 4 core slip ring, so just waiting on the gimbal motor (with the large bore).  To give a keyed position I have a line sensor so I will add a reflective line to the gimbal motor spindel.

Stuck again

Posted in The downside of Opensource, The Downside of software development on December 18, 2017 by asteriondaedalus

So, I have my iPEGA bluetooth gamepad and I am wanting it to run from my dopey Android phone that I am using as the mediator for the rover.

Nothing useful for using these gamepads in Processing for Android so that appears to be out.

No heart or interest to write something in Java.

Python?  Well pygame for Android seems a dud, a lot of old blog entries but nothing obviously working anymore.

I noted that they sorted some of the flakiness of Kivy and so I re-installed Kivy on my PC with the view of prototyping on Windoze then bombing on Android.

Go figure I can get the pyGame gamepad exerciser working on PC.  I tried the same for the raw Kivy version.   I works!  Well as long as you don’t allow your gamepad to go to sleep.  If you do, Kivy drops it.  And, if you leave it disconnected long enough, the Kivy application closes down quietly.

Posted a question on Kivy.org and an issue on github but no responses at all from anyone.

It is not obvious from the Kivy code why it drops the gamepad.  There is otherwise no hints in any of the examples or any of the documentation.

In the pygame version, the gamepad can go to sleep and when it wakes it is auto-connected again.

So, stuck as I still have to see if I can get the old pygame for android to work with the gamepad.  I would have used Kivy but help is a dead end.


Cheap lidar

Posted in Home Made Lidar, Sensing on December 9, 2017 by asteriondaedalus

So my Benewake TF Mini LiDAR turned up.


Now for the fun.

It has to rotate in a circle to create a scan.

I had an idea to mount either of a Seeeduino Film or an ESP8266, with battery, on a spindle to wirelessly send readings – all while it is spinning.

Then BOOM!

You can get “hollow” spindle gimbal motors with slip rings!  So, again a

So, you can attach the TF Mini to the spinning part of the gimbal motor and drive the motor and take readings.

All good but for one thing.  Currently the idea is a open-loop solution.  It will need to be keyed to at least one position (at least) so that the “beams” are relative to a direction.


So, being lazy I found a really cheap MEGA328P driven gimbal board, but I only want it for the gimbal driver and the ease of software hacking.


The beauty is is a clone of the Martinez toy, so it has code to manage the phases of the motor inputs.   Should be interesting as it looks like you only need a few functions to set it up to run a motor continuously, but who knows – I still have to read into the theory.

So much help, so little help

Posted in The Downside of software development on December 8, 2017 by asteriondaedalus

So, I stupidly thought I would upgrade my elixir and crack open my book on Phoenix and plod through the examples while home sick with the flu.

Book is Programming Phoenix (eBook) P1.0 from PragProg

Broke the build so I had to strip out the hex and mix folders, re-installed hex, elixir and phoenix.

And then all I got was the broken connectic with postgres!  Why?  I was going to up from 9odd to 10 but backed out after I saw how long the 10 would take to download (and it wasn’t needed).  I had already uninstalled 9 and just re-installed.  BUT the build would fail as the username/password failed on authentication.


When you delete postgres on windows it doesn’t, of course, remove the data directory (where usernames and passwords are encrypted).   If you reinstall overtop a bug or quirk of the install is that it not longer prompts for super-user password or port etc.  (obviously buried in the data directory).

All fixed by manually deleting the data directory and re-re-installing postgres.


GAG!  My book appears to be out of date now!

At least, they have moved all the app directory structures around.

Pragmatic Programmers KEEP UP!

Although, it looks to be the difference between Phoenix versions 1.2 and 1.3 which is fine (just have to remember to use the phoenix.x rather than phx.x idiom for building apps).


There are problems with the errata page, as rather than the author drafting errata, as people report the problems, the errata is like a user group and so you get the same drifting away from facts.

Although, problems include movement in version of ecto as well.

If there is an error, go figure there will be at least two solutions offered by readers BUT as they don’t state the elixir, phoenix and ecto versions that they are using (while working through the book) you need likely try each of the different solutions until one works for you.

Looks like best option is to install the elixir, ecto and phoenix versions from the book.

Still, I have had to work things out that don’t appear to have been reported in the errata so I guess I am learning little tit bits along the way.