Pan & Tilt bracket with 2 servo motors

Hi,

I got few of those Pan and Tilt Brackets with 2 mini servos and they are currently being auctioned on eBay. Check it here

Pan Tilt Servo Bracket robots Arduino Sparkfun Pololu

Full spec is in the ad.

These brackets are realy fenomenal for robotic projects. Use them to make your sensors scan around or mount a video camera on them.

I hate to ruin your day but, this is the company that manufactures them, and they are half the price there.

Sure, check the postage. It is $20.

That’s cool, how does the little servo hold up when the bracket is at 45*? Most, if not all of the larger brackets cause the servo to struggle a bit - eating valuable power

I haven’t noticed any problems. Obviously there are upper and lower limits to which servos will go. But that is all. You can replace servos with stronger ones.

Please have a look at this video, to see them in action: Arduino Servo Pan Tilt - Big Wiggle Rain Dance . Ignore my blurb :-X

Mine :wink:

did you get it from me, on eBay?

I have Nunchuck, but need code. Could you publish code here?

Yes, I got it from you.

Nunchuck

#include <Wire.h>
#include "nunchuck_funcs.h"
#include <Servo.h> 

byte accx,accy,zbut,cbut;
int ledPin = 13;

Servo myservo;
Servo myservo2;

long previousMillis = 0;

void setup()
{
  myservo.attach(7);
  myservo2.attach(6);
  
    Serial.begin(19200);
    nunchuck_setpowerpins();
    nunchuck_init(); // send the initilization handshake
    
    Serial.print("WiiChuckDemo ready\n");
}

void loop()
{
  if (millis() - previousMillis > 100)
  {
        previousMillis = millis();   

        nunchuck_get_data();

        accx  = nunchuck_accelx(); // ranges from approx 70 - 182
        accy  = nunchuck_accely(); // ranges from approx 65 - 173
        zbut = nunchuck_zbutton();
        cbut = nunchuck_cbutton(); 
        
        myservo.write(map(accx, 70, 182, 0, 180));
        myservo2.write(map(accy, 65, 173, 0, 180));
            
        Serial.print("accx: "); Serial.print((byte)accx,DEC);
        Serial.print("\taccy: "); Serial.print((byte)accy,DEC);
        Serial.print("\tzbut: "); Serial.print((byte)zbut,DEC);
        Serial.print("\tcbut: "); Serial.println((byte)cbut,DEC);
  }
}

I’ve just discovered how to insert a video. Here is mine as well: :slight_smile:

Here are 2 that are much cheaper. They seem flimsy, but have proven to be pretty strong.

Small - US$ 3.99: FPV Fiberglass Pan-Tilt Camera Mount

A little bigger US$ 4.99: FPV Fiberglass Pan-Tilt Camera Mount L-Size

Since you’ve done a bit of engineering on this already…

What type of servos might you use to make something similar, but with more weight capacity? The intended pan/tilt would be able to support say, two or three pounds at least (Digital SLR + lens)… though the speed of seek to desired location need not be too fast. It’d be nice to put together an auto-panner, and also use it coupled to some IR sensors to do wildlife photography, for example, if it were something like fifty bucks to put together. I’m sure I’m far from the first to ask the question. Bugger of it is, if webcams used better sensors and optics, then you could use something like this to composite together gigapixel images from 640x480 shots stitched in software… as it stands, the noise factor in webcam sensors makes it kinda pointless :wink:

Very hard to determine the size of the servo’s, but it looks something like this http://www.dealextreme.com/details.dx/sku.4490 for this one http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?aff=5361&idProduct=12875

The intended pan/tilt would be able to support say, two or three pounds at least

There’s no way you can do that with the style of bracket DROBNJAK is selling. Especially not with cheap Chinese servos full of plastic gears and bushings: they just won’t stand up to the loads involved.

I’ve been working on a design that I haven’t built yet, using a lazy susan bearing for panning, and a tilt mechanism similar to the one in that hobbyking design CrashingDutchman linked to. The key is that the servos are used only as motors, not as bearings. For a heavier load like your DSLR, I’d be inclined to go with a geared stepper, but a really heavy-duty servo might be enough.

This approach is based on my experience with commercial pan-tilt mounts for video cameras: they had to be a lot heavier-duty than I thought was needed when I first started working with them. You don’t need the same smoothness of motion, but you definitely want something with near-zero slop to avoid vibration while stopped.

A stepper like this or this might work better for doing the tilt than a servo. Especiakly with a heavy load.

I’ve seen on YouTube some videos of full size, metal gear servos, rated 32kg/cm pulling 4 full crates of Coca Cola. As I remember, each crate had 3x4 bottles of 2 l Coca Cola. So if you want to put a DSLR onto it, go for one of those. There are few around. You can buy some aluminum sheet, say 1mm thick, on eBay and cut and bend it into strong brackets.

A bit of trial and error.

I’ve seen on YouTube some videos of full size, metal gear servos, rated 32kg/cm pulling 4 full crates of Coca Cola.

And I’ve seen the prices on those servos: I did come across one that was selling for only about $150, but mostly they have list prices on the order of $300 and street prices around $200. Each.

That’s almost 10 times focalist’s budget (which is a little iffy, but do-able with a little luck in finding good deals on servos/steppers, and a design that doesn’t rely on brute force).

Add to the fact that 1mm aluminium and strength don’t go together in the same phrase…
With such beasts I would use 5-6mm aluminium or ticker, to remove weight, just do some holes in it.

I’ll add my tuppence worth and say that I bought one of those set ups ages ago and it’s great for me. I’ve got a webcam attached to it and a thumbpad to move it around, it all works fine.