Mad scientists...

Oscilloscopes

You can't quite earn your mad scientist badge without having one of these babies...
I can't even remember where I obtained this, but it's lovely...
Analogue dials!

New power supply

Having screwed up three power supplies so far, here is the new one...



Here's the previous plug, with delightful casing, but defunct supply!



I believe this time it was the vibration from the sander breaking the innards of the supply :(

Moving automaton head electronics from test-bed to in situ base

On the bench. Trying to transfer the patched electronics from the nice easy patch-cable connections of the test bed to the real, hard-wired circuit in the final location of the base of the automaton head.

Testing the pots...

The arduino screwed down in place, in final location inside base.

 
Connecting up all the wires that need to be at the positive (+5V) voltage, by threading through a circuit board, to be soldered together.

Final +5V "rail" with all +5v connections soldered together

Connecting up all the wires that need to be at earth (ground), by threading through a circuit board, to be soldered together.

Final earth (ground) "rail" with all earth connections soldered together

The final circuit in place in the base, next to the conceptual circuit layout diagram.

Fitting arduino electronics into the automaton base in practise

Having finalised the circuit, it needs to move from test bed to final location with the base the automaton sits on... Here is what the arduino test bed looks like. Spaghetti everywhere. Most of which is just convenience wiring to help.


This is the circuit drawn out in beautiful hand-drawn pen.

This is the head on it's base (not finished here)

This is the box and how it opens out showing the space available

So here is the tidied up circuit diagram showing approximate location of the electronics. Next to it, is the box with the control pots in place.

New simpler electronics

I have bought a fine bag of potentiometers. How sad!

They are presumably culled from some beautiful old stereos, but anyway...

Here is the more or less final circuitry. I have decided not to tackle the power issue about servos only getting  current on a change of signal. This is a cop out, but it's time to move on.

Power
however, I have introdcued a transistor to step up the current to the eyeball LEDs.

This does make them a little brighter

Arduino servos and power burnout...

Wanting to complete my automata-based reading lamp, but having had a lot of servo burnouts, I am trying to prevent the servo getting any power in between position changes. This should greatly reduce the risk of heating.
struggling with the circuit.

If I us digital pin outputs, an output voltage can easily be turned to HIGH (5V) or LOW (0V), but only seems to work with no servos attached. When they are attached the voltage is only 2.5V.

not sure what I'm doing wrong

valPot1 = analogRead(potPin1);            // reads the value of the potentiometer (value between 0 and 1023)
  if ((valPot1 <= midLow)or (valPot1>= midHigh)) {
     digitalWrite (PowerPin,HIGH); //turn on power to servos briefly only at point of writing to allow movement;
     digitalWrite (ledPinJoystick,HIGH);
    // potActive1=true;
    valPot1 = map(valPot1, 150, 900, 0, 179);     // scale it to use it with the servo (value between 0 and 180)
 
    myservo.write(valPot1);                  // sets the servo position according to the scaled value
 
    delay(delay_val);
 digitalWrite (PowerPin,LOW); //turn off power to servos again once moved to reduce heating effect;  
  }
  else {
    digitalWrite (ledPinJoystick,LOW); // signal that value is in mid-range dead-spot - used to turn off LED that indicates joystick activity;
    digitalWrite (PowerPin,LOW); //turn off power to servos when inactive;
  }

Head needs a controller

The remote control automata reading lamp head needs a suitably daft controller.
It uses a playstation 2 analog joystick as the input device,

but this needs something more anatomical to skin it with. It has been suggested a hand would be rather ironically appropriate. It should look like this, but match the MDF finish of the head

image from wpclipart.com

Making high power (3W) LED eyeballs for the automaton

New eyeballs

The eyeballs in my automaton head work OK, but are woefully underpowered. Time to make some new ones!
This is looking at the basic starting point of a detachable eyeball from the front look towards the back. The hole is where the housing goes.

The housing is the (more or less) parabolic reflector from a torch

The eyeball is made detachable by adding a rubber grommet, which allows it to be pushed tight onto the servo control rod. The rubber friction holds it tightly in place.

The eyeballs are ready to attach, although not cosmetically finished yet.

Here they are hooked up to the breadboard to test how they work

They are remarkably more powerful. Each LED is 3W, which is pretty bright. It hurts t0 look straight into them

You can see how much more powerful the 3W led is on the left


Here the test is to see how much light they give off in total darkness. The head is meant to be a bedside/reading lamp with remote control directable beam, via the eyeballs.

Testing shows this is plenty of light!

Close-up it's easier to see how much light is given off.

Hacking VHS players for spare electronics parts

This is the inside of a dead VHS video recorder/player. It turns out it is still full of lots of old-school eletronics. Sure, there are lots of PCBs, but due to the mecahnical nature of video players with their big motors and stuff, there are a lot of useful connectors in there, as well as some high power resistors, transistors, loads of potentiometers and so on. A good way to pick up cheap parts.
Here is a handy 10 pin connector with the wiring all nicely connected. Try soldering anything remotely as neat as this, and you will see how useful a ready made is!

Here it is connected up to the breadboard jump leads coming off the arduino

And here it is fed into the underside of the head, from the board