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DIY STEADICAM v 1.01
May 27, 2009, 3:00 am
Filed under: Photo/Video | Tags: , , , , , , ,

I added a Bogen 357 Quick Release Plate. Plus I’m working on a remote follow focus using a servo with arduino’s and xbee’s. WHAAAT?

This is the code for the sending arduino with the potentiometer

// SENDER

#define sensorPin 0 // analog pin 0 used to connect the potentiometer
#define threshold 0 // threshold for sending out values

int val; // variable to read the value from the analog pin
int lastSensorReading = 0;

void setup()
{
// start serial port at 19200 bps
Serial.begin(9600);
}

void loop()
{
char sensorValue = readSensor();

if (sensorValue > 0){

Serial.print(sensorValue, DEC); // print the value
Serial.print("\r");
delay(20);
}
}

char readSensor(){
char message = 0;

int sensorReading = analogRead(sensorPin);

sensorReading = map(sensorReading, 0, 1023, 0, 179); // scale it to use it with the servo (value between 0 and 180)

if (abs(sensorReading - lastSensorReading) > threshold) {
message = sensorReading;
lastSensorReading = sensorReading;
}
return message;
}

// End Sender

This is the code for the receiving arduino with the servo’


// RECIEVER

int val;
int inByte= 0;
char inString[6];
int stringPos = 0;

#include

Servo myservo; // create servo object to control a servo

void setup() {

// start serial port at 19200 bps
Serial.begin(9600);
Serial.println("Ready!");

myservo.attach(9); // attaches the servo on pin 9 to the servo object

}

void loop() {
if (Serial.available() > 0) { // are there any bytes available on the serial port ???

handleSerial();
}
}

//------------
void handleSerial() {

inByte = Serial.read();
if ((inByte >= '0') && (inByte <= '9')) {
inString[stringPos] = inByte;
stringPos++;
}

if (inByte =='\r') {
int val = atoi(inString);
Serial.println(val);
myservo.write(val); // sets the servo position according to the scaled value
delay(15);

for (int c = 0; c < stringPos; c++) {
inString[c] = 0;
}
}
}
//------------

// End Reciever



DIY Steadicam
May 2, 2009, 1:35 pm
Filed under: Photo/Video | Tags: , , , , , ,

DIY Steadicam

I’ve been working on a camera rig for my Nikon D90. This design is based on the Merlin Steadicam, but since I don’t have 800 bucks to dish out on something that should cost 150 max (I’d rather get that 70-200mm zoom – “the bazooka”), I managed to do it for 12 bucks. Yes I had a lot of freebies (like the bearings and the aluminum)

I have to give credit to WSCLATER from diycamera.com for the design and the brilliant idea of using a universal joint usually found in radio controlled toy cars and trucks. He has been a great help and has lots of goodies on his site, so make sure you check it out!

I’m using the the TRAXXAS driveshaft for the joint and skateboard wheel bearings.

traxxas driveshaft

Traxxas Driveshaft Assembly

dsc_0017
I’ve been able to use my school’s shop to machine all the parts to make the joint fit into a handle and into the camera plate.

As you can see from the above picture, I turned a handle from aluminum round stock on a lathe. Put a set screw on the side of it so that when the ball bearing/traxxas joint assembly is put in, it can be secured. From left to right we have:
-the handle 1.5″ aluminum handle (milled from raw aluminum round strock)
– nut, washer, skateboard ball bearing, washer that all go on a threaded piece 1/4 20 bolt that I cut off to the right size. I had to file the bolt so that it was smaller so that the ball bearing would fit, and then thread the end of it (left end) so that the nut could be used to tighten the ball bearing. The other end of the bolt screws into the traxxas joint that I had to cut to the right size and thread. The other end (right) of the traxxas joint was threaded so that it could screw into another piece of aluminum round stock that then attached to the bottom plate of the rig.
– The plate is made of two parts. The bottom part, with the slit, is 1/4 inch aluminum that’s been milled so the slit can be used as a sliding adjustment for the forward/backward tuning of the rig. I then used four bolts that screw into another, 3 inch aluminum c-channel. I used spacers to offset the two plates. I guess you can use washers for that or get some spacers at your hardware store. WSCLATER has this kind of design that I appropriated. The c-channel has been cut in front into a triangle shape and bent so that it could receive the bent arm. The connection between the top plate and the bent arm could be made more elegantly, but I found it was very sturdy so I just left it alone.
– The arm is made of .5″ (I think) aluminum tube with a very thin wall. It is bent according to a very particular, scientifically calculated shape… ahh… NO, that’s not true, is it? I just sketched a shape that looked “right” and bent the tubing to that shape. The arm has a hole drilled in the front so that a forward weight can be attached. I just drilled a hole and used a carriage bolt to attach the weights. You can use washers as weights although they get expensive so I just used steel round stock that I had in the shop. The bottom of the tube is using the leftover traxxas shaft that I cut off. It is jammed into the tubing (fit almost perfectly) so that a bolt can be screwed into the end of the bent arm and the bottom weight can be attached.

To finish off the rig, I attached a Boghen sliding quick release plate to the top aluminum plate. This allows me to nicely attach the camera but most importantly it allows me to tune the rig so it stays balanced sideways. Look at this video to see what I’m talking about.

Balancing is crucial ! The right position of the camera, the right weight is very important. Start out with the bottom weight. Add just enough weight so that when you perform the “drop test” (look it up on merlin site) the camera rig should swing back from horizontal to vertical in about 1 second. Watch the quick start guide on youtube *it’s kinda funny* also you can download the merlin manual for more info. If you have TOO much weight on the bottom your rig will sway as you move it from side to side, when that weight is just right, there will be no swaying.

I hope this kind of explains the build. As you can see most of these parts are machined from scratch, except the joint, ball bearing, bolts, and the quick release plate… sorry, there really isn’t a list of off the shelf parts.

Here is the test… [blog]

Here are some pictures…

TRAXXAS