Arduino Tank with Nerf Launcher

I added the 3D Printed Nerf Launcher to the Arduino controlled tank.  I can control it from my phone via Bluetooth control.  I used a standard servo to make the attachment.  This gives me up/down capability.

The interface uses 1K ohm resistors to TIP127 transistors to turn the motors on and off.  The small servo doing the pushing had its electronics removed and was modified for infinite 360 degree operation.

Here are some pictures of the insides of the tank.

Here is the YouTube video of the tank with Nerf launcher in operation

InMoov head Working with Arduino UNO

I am just finishing up building the InMoov Robot head.  First you must know that there are about four revisions for every part.  For instance I did the earlier version of the eyes first.  They had very limited range of motion.  So I made a newer version and they had much better movement.

I also tried painting the parts for the first time.  I used paint-able caulk first, then several layers of a sand-able undercoat followed by at least 2 layers of paint.  This next picture shows the results.

This is what it looked like before painting, the holes have been filled with caulk. I do not know why there are so many holes in the design!

This is what the eye assembly looked like.  I modified it slightly to fit an older Logitech webcam guts.  However the camera was upside down when it was tested.

I modified the gear for the mouth and the ears as well.  I wanted ears that were fairly flat, but that resulted in the magnet hitting the jaw mechanism.  I will have to find some lower profile speakers.

I also located and added a base.  The real inMoov robot has more than just a head, but I wanted to stop there for now.  I had to cut the throat piston off at about one inch shorter to fit properly with the stand.

Here is what the completed robot head looked like.

I also recorded a video of me testing the servos to see if everything worked.  I used some MG958 servos that are twice as powerful as standard servos but I was not sure if they would be powerful enough.

 

EZ Robot JD Humanoid Painting and Repairs.

My third humanoid robot is working to some degree.  I have had lots of problems with the 3D printed parts.  The filament was likely the issue because I have used 2 other filaments that did not break as easily.  His feet kept beaking amoung other things.  I glued them back together several times.  Then I finally gave up and used metal servo brackets to fix his feet.

First I removed what was left of the broken parts leaving a smooth surface.

Next I mounted the metal bracket as shown in the picture below.  I should have used the other two outside holes as the bracket angles up slightly.  Note the use of a servo mounting spacer to make the screw a little longer.

Then the servo is mounted to the bracket as shown in the next picture.  Be sure to screw the servo center to the leg piece first, then screw the servo to the metal bracket.  His shoes do not fit over the metal bracket so it might need to be modified as far as the bracket height goes.

Another issue with the filament I was using is how bad it looks.  I printed the torso on its flat side so it took 30% less time and less filament.  However that left the surface looking a little rough.  I watched several videos and then decided to prime and paint it.  I used three layers of sandable primer with light sanding between them.  BTW I did the same thing with his shoes to save time and filament.  However the two cans of spray paint were nearly $20!!

This shows how bad the torso looked. It has been lightly sanded for this picture.

After three coats of primer with light sanding betwen them it already looks better.

Then the final product, it looks really good!  Issues included needing to fix any cracks before you start.  There were some cracks on the sides that are still visable.  You can use a soldering iron on the inside to carefully melt them back together.  I had previously reinforced some of the bottom with plastic pieces glued across the layers to hold them together.

Dual 80x160 RGB LCD Robot eyes

My latest creation uses dual 80x160 RGB LCD's to produce two robot eyes.  They are wired together so they can not "wink".  On the other hand it only takes half of the code.  They are powered by an Arduino UNO.  I was going to do this with OLED's but someone sent me a LCD instead so I went with the LCD's.  Theoretically you can wire them to have different "CS" or chip selects so each eye would be independent.  I added some more circles.  There is a small white circle on the far left and right as well as a black circle that produces the ring around the blue of the eyes.

By the way these LCD's are five volt friendly and easily run off five volts as well as use five volt logic levels.

Here are a couple of pictures.  They are more blue in reality but the camera has issues with the blue.

Here is a video of them on YouTube.

Ideally you could have two channels of your 32 channel servo controller go to analog inputs of an Arduino to set the size and direction of the eyes.

Here is the code:

// Sample program for eyes on 80x160 TFT LCD Screen

// March 2022 by Bob Davis

#include <TFT.h>  // Arduino LCD library

#include <SPI.h>

 

// Pins

#define cs   10

#define dc   8

#define rst  9

// For Arduino Uno: MOSI = pin 11 and SCLK = pin 13.  

// Create an instance of the library

TFT TFTscreen = TFT(cs, dc, rst);

int width=160; 

void setup() {

 

   // Initialize the screen

   TFTscreen.begin();

   // Clear the screen

   TFTscreen.background(255,255,255);

   // Set font color to white

   TFTscreen.stroke(255,255,255);

   // Set the font size

   TFTscreen.setTextSize(2);

   // Write some text on the screen

//   TFTscreen.text("Hello World!",0,0);

}

 

void loop() {

   TFTscreen.background(255,255,255); // Clear Screen

   // Eyes Center  NOTE SCREEN IS UPSIDE DOWN 0,0=bottom right

   TFTscreen.fillCircle(25,65,15,0x0000);

   TFTscreen.fillCircle(135,65,15,0x0000); 

   TFTscreen.fillCircle(45,65,30,0x0000);

   TFTscreen.fillCircle(115,65,30,0x0000); 

   TFTscreen.fillRect(45,35,70,61,0x0000); // Connect Circles

   TFTscreen.fillCircle(80,65,35,0xFFFF);

   TFTscreen.fillCircle(80,65,30,0xFFE0);

   TFTscreen.fillCircle(80,65,10,0xFFFF);

   delay(1000);

   // Eyes Narrow

   TFTscreen.fill(255,255,255);

   TFTscreen.rect(0,30,160,20);

   TFTscreen.rect(0,78,160,21);

   delay(1000);

   // Eyes Right

//   TFTscreen.background(255,255,255);

   TFTscreen.fillCircle(25,65,15,0x0000);

   TFTscreen.fillCircle(135,65,15,0x0000); 

   TFTscreen.fillCircle(45,65,30,0x0000);

   TFTscreen.fillCircle(115,65,30,0x0000); 

   TFTscreen.fillRect(45,35,70,61,0x0000);// Connect Circles

   TFTscreen.fillCircle(110,65,35,0xFFFF);

   TFTscreen.fillCircle(110,65,30,0xFFE0);

   TFTscreen.fillCircle(110,65,10,0xFFFF);

   delay(1000);

   

   // Eyes Left

//   TFTscreen.background(255,255,255);

   TFTscreen.fillCircle(25,65,15,0x0000);

   TFTscreen.fillCircle(135,65,15,0x0000); 

   TFTscreen.fillCircle(45,65,30,0x0000);

   TFTscreen.fillCircle(115,65,30,0x0000); 

   TFTscreen.fillRect(45,35,70,61,0x0000);// Connect Circles

   TFTscreen.fillCircle(50,65,35,0xFFFF);

   TFTscreen.fillCircle(50,65,30,0xFFE0); // Blue

   TFTscreen.fillCircle(50,65,10,0xFFFF);

   delay(1000);

    

   // Eyes Big

   TFTscreen.fillCircle(25,65,15,0x0000);

   TFTscreen.fillCircle(135,65,15,0x0000); 

   TFTscreen.fillCircle(45,65,30,0x0000);

   TFTscreen.fillCircle(115,65,30,0x0000); 

   TFTscreen.fillCircle(60,65,40,0x0000);

   TFTscreen.fillCircle(100,65,40,0x0000); 

   TFTscreen.fillRect(65,25,40,81,0x0000); // Connect Circles

   TFTscreen.fillCircle(80,65,35,0xFFFF);

   TFTscreen.fillCircle(80,65,30,0xFFE0);

   TFTscreen.fillCircle(80,65,10,0xFFFF);

   delay(2000);

}

Improved Arduino Robot Face on Parallel TFT LCD

Improved the Arduino Robot Face by putting it on a 2.4 inch Parallel LCD. The LCD is a HY-TFT240 to be exact. This larger 320 by 240 LCD gives more room for adding a mouth as well as bigger eyes. However the LCD requires 8 data bits, 4 control lines power and ground. So there are more wires required. You can even get this type of LCD in a shield that plugs right into the Arduino. That arrangement will not fit in the robots head.

Here are two of the many possible faces.

This is what the setup looks like when it is not installed in the robot.

This is the video of the robot faces.

This is the code. I do not have an interface to select what face to display yet.

// Parallel LCD to Robot Face

// By Bob Davis

// Adafruit_TFTLCD LIBRARY MUST BE CONFIGURED.

// SEE RELEVANT COMMENTS IN Adafruit_TFTLCD.h.

// Some code by Open-Smart Team and Catalex Team

//

// Board: Arduino UNO R3 or Arduino Mega2560

// ADAFRUIT DRIVERS

#include <Adafruit_GFX.h>    // Core graphics library

#include <Adafruit_TFTLCD.h> // Hardware-specific library

#define LCD_CS A3 // Chip Select goes to Analog 3

#define LCD_CD A2 // Command/Data goes to Analog 2

#define LCD_WR A1 // LCD Write goes to Analog 1

#define LCD_RD A0 // LCD Read goes to Analog 0

#define LCD_RESET A4 // Actually use Arduino's reset pin

Adafruit_TFTLCD tft(LCD_CS, LCD_CD, LCD_WR, LCD_RD, LCD_RESET);

//*********************************************//

// Pin assignments for the LCD *ADAFRUIT*

// GND           -- GND

// 3V3           -- 3.3V

// CS            -- A3  

// RS            -- A2

// WR            -- A1

// RD            -- A0

// RST           -- RESET or resistor to +V

// LED           -- GND

// DB0-DB7       -- 8, 9, 2, 3, 4, 5, 6, 7

int width=320;  // scales 

int height=240;

// uint16_t g_identifier;

// Assign names to color values:

#define BLACK   0x0000

#define BLUE    0x001F

#define RED     0xF800

#define GREEN   0x07E0

#define CYAN    0x07FF

#define MAGENTA 0xF81F

#define YELLOW  0xFFE0

#define WHITE   0xFFFF

void setup(void) {

  uint16_t identifier = 0x9325; // or 9341

//  tft.reset();

  tft.begin(identifier);

  tft.setRotation(1);

//  tft.setCursor(0, 0);

  tft.fillRect(0, 0, width, height, BLACK);

}

void loop(void) {

   tft.fillRect(0, 0, width, height, BLACK);

   // Eyes Center

   tft.fillCircle(width*.1,height*.2,20,WHITE);

   tft.fillCircle(width*.1+40,height*.2,20,WHITE); // oblong fillCircle

   tft.fillRect  (width*.1,height*.2-20,40,41,WHITE);

   tft.fillCircle(width*.1+20,height*.2,20, BLUE);

   tft.fillCircle(width*.1+20,height*.2,10, BLACK);

   tft.fillCircle(width*.8,height*.2,20,WHITE);

   tft.fillCircle(width*.8+40,height*.2,20,WHITE); // oblong fillCircle

   tft.fillRect  (width*.8,height*.2-20,40,41,WHITE);

   tft.fillCircle(width*.8+20,height*.2,20, BLUE);

   tft.fillCircle(width*.8+20,height*.2,10, BLACK);

    // Mouth

   tft.fillCircle(width*.2,height*.8,20,WHITE);

   tft.fillCircle(width*.8,height*.8,20,WHITE); // oblong fillCircle

   tft.fillRect(width*.2,height*.8-20,width*.6,41,WHITE);

   delay(1000);

   // Eyes Narrow

   tft.fillRect(0,height*.2-20,width,10,BLACK);

   tft.fillRect(0,height*.2+10,width,11,BLACK);

   delay(1000);

   

   // Eyes Big

   tft.fillCircle(width*.1,height*.2,30,WHITE);

   tft.fillCircle(width*.1+40,height*.2,30,WHITE); // oblong fillCircle

   tft.fillRect  (width*.1,height*.2-30,45,61,WHITE);

   tft.fillCircle(width*.1+20,height*.2,20,BLUE);

   tft.fillCircle(width*.1+20,height*.2,10,BLACK);

   tft.fillCircle(width*.78,height*.2,30,WHITE);

   tft.fillCircle(width*.78+40,height*.2,30,WHITE); // oblong fillCircle

   tft.fillRect  (width*.78,height*.2-30,45,61,WHITE);

   tft.fillCircle(width*.78+20,height*.2,20,BLUE);

   tft.fillCircle(width*.78+20,height*.2,10,BLACK);

   // Big Mouth

   tft.fillCircle(width*.2,height*.8,30,WHITE);

   tft.fillCircle(width*.8,height*.8,30,WHITE); // oblong fillCircle

   tft.fillRect(width*.2,height*.8-30,width*.6,61,WHITE);

   tft.fillCircle(width*.2,height*.8,20,BLACK);

   tft.fillCircle(width*.8,height*.8,20,BLACK); // oblong fillCircle

   tft.fillRect(width*.2,height*.8-20,width*.6,41,BLACK);

   delay(1000);

   tft.fillRect(0,0,width,height,BLACK); // Erase 

   // Eyes Right

   tft.fillCircle(width*.1,height*.2,20,WHITE);

   tft.fillCircle(width*.1+40,height*.2,20,WHITE); // oblong fillCircle

   tft.fillRect  (width*.1,height*.2-20,40,41,WHITE);

   tft.fillCircle(width*.1+35,height*.2,20, BLUE);

   tft.fillCircle(width*.1+35,height*.2,10, BLACK);

   tft.fillCircle(width*.8,height*.2,20,WHITE);

   tft.fillCircle(width*.8+40,height*.2,20,WHITE); // oblong fillCircle

   tft.fillRect  (width*.8,height*.2-20,40,41,WHITE);

   tft.fillCircle(width*.8+35,height*.2,20, BLUE);

   tft.fillCircle(width*.8+35,height*.2,10, BLACK);

   // Narrow Mouth

   tft.fillCircle(width*.2,height*.8,10,WHITE);

   tft.fillCircle(width*.8,height*.8,10,WHITE); // oblong fillCircle

   tft.fillRect(width*.2,height*.8-10,width*.6,21,WHITE);

   delay(1000);

   

   // Eyes Left

   tft.fillCircle(width*.1,height*.2,20,WHITE);

   tft.fillCircle(width*.1+40,height*.2,20,WHITE); // oblong fillCircle

   tft.fillRect  (width*.1,height*.2-20,40,41,WHITE);

   tft.fillCircle(width*.1+5,height*.2,20, BLUE);

   tft.fillCircle(width*.1+5,height*.2,10, BLACK);

   tft.fillCircle(width*.8,height*.2,20,WHITE);

   tft.fillCircle(width*.8+40,height*.2,20,WHITE); // oblong fillCircle

   tft.fillRect  (width*.8,height*.2-20,40,41,WHITE);

   tft.fillCircle(width*.8+5,height*.2,20, BLUE);

   tft.fillCircle(width*.8+5,height*.2,10, BLACK);

    // Mouth

   tft.fillCircle(width*.2,height*.8,10,WHITE);

   tft.fillCircle(width*.8,height*.8,10,WHITE); // oblong fillCircle

   tft.fillRect(width*.2,height*.8-10,width*.6,21,WHITE);

   delay(1000);

}

Nokia 5110 Robot Face Eyes and Mouth

 I thought I would try using a Nokia LCD for creating a face for my robot.  However I was greatly disappointed.  If you make his eyes white, then the border is also white.  So I had to make his eyes black.  The effect is not nearly as pronounced.  As a result I only created two expressions for this LCD.

Here is the two faces:

Here is the code for those two faces.

/*********************************************************************
Nokia 5110 LCD Robot Face
Many thankls to AdaFruit!
*********************************************************************/
#include <Adafruit_GFX.h>
#include <Adafruit_PCD8544.h>
// Software SPI (slower updates, more flexible pin options):
// pin 7 21- Serial clock out (SCLK)
// pin 6 20- Serial data out (DIN)
// pin 5 19- Data/Command select (D/C)
// pin 4 18- LCD chip select (CS)
// pin 3 17- LCD reset (RST)
//Adafruit_PCD8544 display = Adafruit_PCD8544(21, 20, 19, 18, 17);
Adafruit_PCD8544 display = Adafruit_PCD8544(7, 6, 5, 4, 3);
void setup()   {
  display.begin();
  display.setContrast(60);  // Default is 50
  display.clearDisplay();   // clears the screen and buffer
}
void loop() {
  // draw big eyes and mouth
  display.fillCircle(display.width()/6, display.height()/5, 10, BLACK);
  display.fillCircle(display.width()/6*5, display.height()/5, 10, BLACK);
  display.fillCircle(display.width()/4, display.height()-10, 10, BLACK);
  display.fillCircle(display.width()/4*3, display.height()-10, 10, BLACK);
  display.fillRect(display.width()/4, display.height()-20,display.width()/4*2,20, BLACK);
  display.display();
  delay(2000);
  display.clearDisplay();
  // draw eyes and mouth
  display.fillCircle(display.width()/6, display.height()/5, 7, BLACK);
  display.fillCircle(display.width()/6*5, display.height()/5, 7, BLACK);
  display.fillCircle(display.width()/4, display.height()-10, 5, BLACK);
  display.fillCircle(display.width()/4*3, display.height()-10, 5, BLACK);
  display.fillRect(display.width()/4, display.height()-14,display.width()/4*2,10,BLACK);
  display.display();
  delay(2000);
  display.clearDisplay();
}

I am Making my Third Humanoid Robot

I have started on making my third humanoid robot.  This one is modeled after the EZ-Robot JD Humanoid.  The issue with the larger humanoids is that their center of gravity is way too high.  There is a two degree tolerance in each servo and that is amplified by the distance from the servo's.  So in a humanoid that is over 16" tall the two degrees can amount to falling over frontwards or falling over backwards.  That makes it really hard to write software for walking.  

One solution is to make the robot shorter and to make the distance from each servo shorter.  In the following picture there is a servo for the EZ_Robot on the left, for the Hadron Robot in the middle, and for the mechanical robot sold on eBay on hte right.  The EZ-Robot assembly is so short that the ears need to be cut off the one end of the servo for it to work.  The Hadron robot on the other hand is not much smaller than the mechanical version, it also is not quite square.

As I tried more options the possibilities expanded to five different versions.  I think I will have to design my own!

The robot body would take 16 hours to print as designed.  I turned it over and that reduced the time to 10 hours.  However since there would be supports under the front, the front surface is not a smooth.  

Then I ran into the issue with the shoulder servos needing their tabs cut off.  What is it with the designers and cutting the mounting tabs off the servos??

My solution was to cut some slots in the top for the servo mounting tabs.  I used a soldering iron to do that trick.  BTW when I added the legs the body broke in half!  These parts fit way too tight.  I file them off so they are smooth before even trying to fit them together.

The robot is now about 1/2 way completed.  Here is what he looks like so far.

The next issue was that the shoulders (Servo horn extenders) keep breaking in half.  So I rotated them so they stand up before printing them and that seems to fix the issue.

The U brackets for the legs kept breaking.  So I developed my own design.  

So far I have come up with six different servo U bracket design options.  The five on the left do not require you to cut off the servo mounting tabs and they do not break as easily as the ones normally used for this robot.  Somehow I lost the mounting holes in the fifth one but I added them back in later on.

So far he is coming together. The head has too big of an opening for the LCD screen.  I cut it for a 2.5" LCD but then the screen did not fit because the LCD circuit board was too big.  I may have to make a bezel for the LCD to cover the mistakes.....

I almost gave up on his hands.  I have piles of servos but none are the size that properly fit his hands.  There is a size of servo that is in between the SG90/HS55 and the normal sized servo (They are marked "PKZ1060") but even they do not fit.  So I modified the hands to use the SG90 sized servos.  I had to drill out the servo end so the white servo arm would fit through it then I melted a hole for the screw that locks the arm to the printed arm.

I had to remove the left side (It broke off anyway) and then trim a little for the round part of the servo to fit.  Then I used lots of glue to hold the servo in place.  I had trouble with mounting the hands to the arms so I added a screw, as can be seen below the servo in this picture.

Here is what he looks like with his hands attached.  Now to add a servo controller.

This next picture is a size comparison.  JD Humanoid is in the front left.  To the right is the Robosoul HS3 and behind them is the humanoid that is sold on eBay.

Simple Arduino TFT LCD Robot eyes

I am working on making some better "eyes" for my humanoid robots. The 8x8 LED design was cool but I can do a lot more with an LCD screen.  I need to make it more universal to work with different sizes of screens.

This is a link to the video of this robot head being printed:

https://youtu.be/lHc25bKupwc

Here is the code so far:

// Program for Eyes on a 1.8" TFT LCD Screen

#include <TFT.h>  // Arduino LCD library

#include <SPI.h>

 

// Pins

#define cs   10

#define dc   9

#define rst  8

 

// Create an instance of the library

TFT TFTscreen = TFT(cs, dc, rst);

 

void setup() {

 

   // Initialize the screen

   TFTscreen.begin();

 

   // Clear the screen

   TFTscreen.background(0, 0, 0);

 

   // Set font color to white

   TFTscreen.stroke(255,255,255);

 

   // Set the font size

   TFTscreen.setTextSize(2);

 

   // Write some text on the screen

//   TFTscreen.text("Hello World!",0,0);

}

 

void loop() {

   TFTscreen.noStroke();

   // Eyes Center

   TFTscreen.fill(255,255,255);

   TFTscreen.circle(20,60,20);

   TFTscreen.circle(50,60,20); // oblong circle

   TFTscreen.rect(20,40,30,41);

   TFTscreen.fill(255,0,0);

   TFTscreen.circle(35,60,20);

   TFTscreen.fill(0,0,0);

   TFTscreen.circle(35,60,10);

   TFTscreen.fill(255,255,255);

   TFTscreen.circle(110,60,20);

   TFTscreen.circle(140,60,20);// oblong circle

   TFTscreen.rect(110,40,30,41);

   TFTscreen.fill(255,0,0);

   TFTscreen.circle(125,60,20);

   TFTscreen.fill(0,0,0);

   TFTscreen.circle(125,60,10);

   delay(1000);

   // Eyes Narrow

   TFTscreen.fill(0,0,0);

   TFTscreen.rect(0,40,160,10);

   TFTscreen.rect(0,70,160,11);

   delay(1000);

   

   // Eyes Big

   TFTscreen.fill(255,255,255);

   TFTscreen.circle(30,60,30);

   TFTscreen.circle(40,60,30); // oblong circle

   TFTscreen.rect(20,40,30,41);

   TFTscreen.fill(255,0,0);

   TFTscreen.circle(35,60,20);

   TFTscreen.fill(0,0,0);

   TFTscreen.circle(35,60,10);

   TFTscreen.fill(255,255,255);

   TFTscreen.circle(120,60,30);

   TFTscreen.circle(130,60,30);// oblong circle

   TFTscreen.rect(110,40,30,41);

   TFTscreen.fill(255,0,0);

   TFTscreen.circle(125,60,20);

   TFTscreen.fill(0,0,0);

   TFTscreen.circle(125,60,10);

   delay(1000);

   TFTscreen.fill(0,0,0);

   TFTscreen.rect(0,30,160,61); // Erase eyes

   // Eyes Right

   TFTscreen.fill(255,255,255);

   TFTscreen.circle(20,60,20);

   TFTscreen.circle(50,60,20); // oblong circle

   TFTscreen.rect(20,40,30,41);

   TFTscreen.fill(255,0,0);

   TFTscreen.circle(20,60,20);

   TFTscreen.fill(0,0,0);

   TFTscreen.circle(20,60,10);

   TFTscreen.fill(255,255,255);

   TFTscreen.circle(110,60,20);

   TFTscreen.circle(140,60,20);// oblong circle

   TFTscreen.rect(110,40,30,41);

   TFTscreen.fill(255,0,0);

   TFTscreen.circle(110,60,20);

   TFTscreen.fill(0,0,0);

   TFTscreen.circle(110,60,10);

   delay(1000);

   

   // Eyes Left

   TFTscreen.fill(255,255,255);

   TFTscreen.circle(20,60,20);

   TFTscreen.circle(50,60,20); // oblong circle

   TFTscreen.rect(20,40,30,41);

   TFTscreen.fill(255,0,0);

   TFTscreen.circle(50,60,20);

   TFTscreen.fill(0,0,0);

   TFTscreen.circle(50,60,10);

   TFTscreen.fill(255,255,255);

   TFTscreen.circle(110,60,20);

   TFTscreen.circle(140,60,20);// oblong circle

   TFTscreen.rect(110,40,30,41);

   TFTscreen.fill(255,0,0);

   TFTscreen.circle(140,60,20);

   TFTscreen.fill(0,0,0);

   TFTscreen.circle(140,60,10);

   delay(1000);

 

}

Rebuild of the 17 DOF Humanoid Robot found on eBay

 In my book "Arduino Servo Projects" I made all kinds of Humanoid Robots.  But none of them were the 17 DOF Humanoid as is found on eBay.  I just could not get it to work.  It has a high tendency to fall over a lot.  In this guys video it fell off the table: https://www.youtube.com/watch?v=-gQDgxQkX-w !  So I spent some time trying to fix him.  One thing I noticed is that his legs are too long.  Even with the higher power MG958 servos when he falls over and I pick him up the servos then go to where they were supposed to.  The servos just cannot lift his weight!  Then as I was studying him I found the mistake!  Can you see it in the pictures below?

Here I am comparing him to the robot from RoboSoul - the HS3 (I made an imitation version and he works just like the real one)

Did you find the problem?  I circled it in red in this picture.  The servo is mounted upside down!

While I was at it I also changed his chest.  The goal there was to make it more like the one that comes in the kit on eBay.  The only difference now is that his head is 3/4 of an inch taller.  I had to move the electronics to the front too.

This first picture is of the new chest bracket on the right.  It closely matches the kit on the left.  The chest is made out of a 3.5 inch piece of three inch by one inch C Channel aluminum.

This is the old chest bracket on the right.  The arms were located higher up and one inch forward of the kit design.  This gave lots of room for the electronics in the back.

I rebuilt my Arduino Servo Arm to use Switches!

This change started as an accident.  Somehow I broke one of the variable resistors that controls the servos in the arm.  So after a while I came up with the idea of using switches instead. For the switches you need 3 position ones.  The positions are on low off and on high.  Then add two 10K resistors across the switch with the two resistors meeting in the middle.  The resulting operation of the arm was much smoother and quieter.  The variable resistors picked up too much noise and that resulted in herky-jerky motion.

This first picture is of the back of the switches.  I used 33K resistors as the value is not critical.

This is the front view of the robot arm controlled by switches.

This is a video of it in operation:

15 DOF Humanoid with PCA9685 and MAX7219

There was not enough pins available on my Arduino UNO to interface a LCD.  I was using 15 pins to control the servos.  So I added a PCA9685 servo controller.  It only uses 2 pins to control 16 servos, thus freeing up many pins for further experiments.  

When I first fired up the PCA9685 shield it quickly smoked.  The polarity protection transistor could not handle the current.  So I replaced it with a jumper wire for now.  The transistor is located next to the power connector near where it says "GND".

Here is the video of the robot:

https://www.youtube.com/watch?v=u30YtSnnPJE

Here are some of the robots facial expressions:

In this picture you can almost see the fear in his eyes!