Ski trip

If you think heart rate graphs are boring, then look at these. This particular graph is taken from a ski trip of mine. My resting heart beat at night was about 50 beats per minute (bpm) and this value tripled, while skiing on the hills.

If you look closer into the time frame of the ski trip, you can see if I was on the ski slope or on the ski lift.

Estimate volume of STL-File in PHP

I needed a PHP-script that gives me the volume of an STL-File for my 3D-Printer.
I took the script from here and modified it to accept STL-Files, which are encoded in ASCII
In most of the cases the volume is an overestimate, but it works.

<!--
Name: stlvolume.php

Date: July 17, 20
-->

<?php



function stlhandling($volume=0,$toobig=0,$filepath){
$x_max = 0;
$y_max = 0;
$z_max = 0;
$x_min = 0;
$y_min = 0;
$z_min = 0;
//$filepath = "4.stl";
//$filepath = "k.stl";
$fp = fopen($filepath, "rb");

$section = file_get_contents($filepath, NULL, NULL, 0, 79);

$sizeoff=filesize( $filepath );

fseek($fp, 80); 
$data = fread($fp, 4);

$numOfFacets = unpack("I", $data);
//echo $numOfFacets[1];
$pointer=12.5*$i+4;
$binary=1;
if(($numOfFacets[1]*12.5)>$sizeoff)$binary=0;

if($binary==0){fseek($fp, 0);
fgets($fp,100);
fgets($fp,100);
fgets($fp,100);
//echo "ascii";
}

echo $numOfFacets[1];
for ($i = 0; $i < $numOfFacets[1]; $i++){
    //Start Normal Vector
  if($binary==1){
    $data = fread($fp, 4);
    $hold = unpack("f", $data);
    $normalVectorsX[$i] = $hold[1];
    $data = fread($fp, 4);
    $hold = unpack("f", $data);
    $normalVectorsY[$i] = $hold[1];
    $data = fread($fp, 4);
    $hold = unpack("f", $data);
    $normalVectorsZ[$i] = $hold[1];
    //End Normal Vector
    //Start Vertex1
    $data = fread($fp, 4);
    $hold = unpack("f", $data);
    $vertex1X[$i] = $hold[1];
    $data = fread($fp, 4);
    $hold = unpack("f", $data);
    $vertex1Y[$i] = $hold[1];
    $data = fread($fp, 4);
    $hold = unpack("f", $data);
    $vertex1Z[$i] = $hold[1];
    //End Vertex1
    //Start Vertex2
    $data = fread($fp, 4);
    $hold = unpack("f", $data);
    $vertex2X[$i] = $hold[1];
    $data = fread($fp, 4);
    $hold = unpack("f", $data);
    $vertex2Y[$i] = $hold[1];
    $data = fread($fp, 4);
    $hold = unpack("f", $data);
    $vertex2Z[$i] = $hold[1];
    //End Vertex2
    //Start Vertex3
    $data = fread($fp, 4);
    $hold = unpack("f", $data);
    $vertex3X[$i] = $hold[1];
    $data = fread($fp, 4);
    $hold = unpack("f", $data);
    $vertex3Y[$i] = $hold[1];
    $data = fread($fp, 4);
    $hold = unpack("f", $data);
    $vertex3Z[$i] = $hold[1];
    //End Vertex3
    //Attribute Byte Count
    $data = fread($fp, 2);
    $hold = unpack("S", $data);
    $abc[$i] = $hold[1];
   }
   if($binary==0){

    //echo substr(fgets($fp,100),13);
    $vertexarray1=explode(" ",substr(fgets($fp,150),13));
    $vertexarray2=explode(" ",substr(fgets($fp,150),13));
    $vertexarray3=explode(" ",substr(fgets($fp,150),13));
    //echo "\n<br>k".floatval($vertexarray1[0]);
    //echo "\n".fgets($fp,100);
    $vertex1X[$i]=$vertexarray1[0];
    $vertex1Y[$i]=$vertexarray1[1];
    $vertex1Z[$i]=$vertexarray1[2];
    $vertex2X[$i]=$vertexarray2[0];
    $vertex2Y[$i]=$vertexarray2[1];
    $vertex2Z[$i]=$vertexarray2[2];
    $vertex3X[$i]=$vertexarray3[0];
    $vertex3Y[$i]=$vertexarray3[1];
    $vertex3Z[$i]=$vertexarray3[2];
    fgets($fp,80);
    fgets($fp,80);
    $ko=fgets($fp,80);
    //echo substr($ko,0,8)."\n<br>";
    if(substr($ko,0,8)=="endsolid")$numOfFacets[1]=$i-1;//found the end of the file
    fgets($fp,190);

  }
   
    $x_vals = array($vertex1X[$i], $vertex2X[$i], $vertex3X[$i]);
    $y_vals = array($vertex1Y[$i], $vertex2Y[$i], $vertex3Y[$i]);
    $z_vals = array($vertex1Z[$i], $vertex2Z[$i], $vertex3Z[$i]);
    if(max($x_vals) > $x_max) {
        $x_max = max($x_vals);
    }
    if(max($y_vals) > $y_max) {
        $y_max = max($y_vals);
    }   
    if(max($z_vals) > $z_max) {
        $z_max = max($z_vals);
    }   
    if(min($x_vals) < $x_min) {
        $x_min = min($x_vals);
    }
    if(min($y_vals) < $y_min) {
        $y_min = min($y_vals);
    }   
    if(min($z_vals) < $z_min) {
        $z_min = min($z_vals);
    }   
   
}
$x_dim = $x_max - $x_min;
$y_dim = $y_max - $y_min;
$z_dim = $z_max - $z_min;

$volume = $x_dim*$y_dim*$z_dim;

$raw_cost = 15;
$tray_cost = $raw_cost;
$material_cost = $raw_cost*$volume*1.02;
$support_cost = $raw_cost*2;
$total = $tray_cost + $material_cost + $support_cost;
echo "$".number_format($total, 2, '.', ',');
$fits=0;
if($x_dim<140 && $x_dim<140 && $z_dim<90)
    $fits=1;
if($x_dim<140 && $x_dim<90 && $z_dim<140)
    $fits=1;
if($x_dim<90 && $x_dim<140 && $z_dim<140)
    $fits=1;
$volumeovercharge=$volume/30000;


$volumeovercharge=round($volumeovercharge,0);


//is volume < 0.5
if($volumeovercharge==0 && $volume>0)$volumeovercharge=1;
if($fits==0)$volumeovercharge=-1;
echo "\n<br>".$x_dim;echo "\n<br>";
echo "$".number_format($volume, 2, '.', ',');
echo "\n<br>".$y_dim;
echo "\n<br>".$z_dim;
echo "\n<br>".$fits;
echo "\n<br>k".$volumeovercharge;

return $volumeovercharge;
}
//stlhandling(0,0,"4.stl");
?>

Huxley Mendel

As you may know there are 3D-Printers that can build themselves and are going to take over the world.

Just kidding.

But I was busy and built an Huxley Mendel.

I also made a picture half into the build process. Please excuse the mess.

Heart rate app

This is my averaged heart rate over the day from the data of 67 days.
So you can see pretty clearly when I am sleeping from eleven to about seven in the morning.
Then I am cycling to work, where you can see the biggest peak.

The heart rate data was captured with an heart rate monitor, which sends the heart rate to my phone and this data is recorded by my app.

After the data gets collected on the phone it is sent to my homepage, where you can see my actual pulse.

Control of the heating installation

This is the actual Labview program that runs on a laptop and controls the water heating system in the house of my parents.

From 2004 to 2009 the system was controlled by a embedded microchip called SC12.

The program was coded by me and you can see the website that was accesible at this time here.

howto make pdfs for kindle with tex

just use this header with your tex files and you get pdfs that are suitable for your kindle

\documentclass[12pt,a5paper,openany,oneside]{book}
\usepackage[a5paper]{geometry}
\usepackage[pdftex,pdftitle={book title},pdfauthor={Doe, John}]{hyperref}
\usepackage[pdftex]{color,graphicx}
\usepackage{graphicx,textcomp,booktabs,amsmath}
\usepackage{mathptmx,courier}
\usepackage[scaled]{helvet}
\usepackage{totpages}
\usepackage{amssymb}
\usepackage[utf8]{inputenc}
\textwidth 128mm
\topmargin -15mm
\textheight 175mm
\evensidemargin -15mm
\oddsidemargin -15mm
\begin{document}
%insert your text here
\end{document}

Djvu to pdf (with cut ability)

Just found a good djvu2pdf converter

http://pd4ml.com/djvu.htm

It is specifically designed for ebook readers
and you can crop the white borders of your djvu file

To install this programm on Linux you need to download the Djvu2pdf.zip on this site for other platforms and goto http://download.eclipse.org/eclipse/downloads/drops/R-3.6.1-201009090800/index.php#SWT and scroll down to download the swt binary and source
extract both archives and put the swt.jar in the Djvu2Pdf/lib from the other archive
To run the programm you have the chmod the run.sh file to 755
chmod 755 run.sh
now you can start ist with
sudo ./run.sh

Now you can load your djvu file into the programm and set the device resolution to 800x600px for the Kindle.
Change the other options as you like and your done.