DIY Camera stabilizer design      
WSCLATER

Stabiliser 1

Stabiliser #1, August 2008

Update,January 2011


Early experiments

This is a DIY (low tech) camera stabilizer in form similar to the MERLIN. I used mostly scrap or surplus materials. The functioning depends on balance and inertia. A piece of 1/8 inch aluminium forms the camera platform. An aluminium torch was reconfigured to act as a handle. It's not an ideal shape for the hand, but the head allows the ball bearing of the gimbal to be held in place satisfactorily. A curved aluminium tube screwed to the camera plate holds the steel washers used as counterweights. The pictures here represent experiments over a period of time, and dimensions and balance configurations are different from time to time.

A crucial element  of the design is the gimbal, and I developed my own low friction design using a universal joint combined with a small ball bearing. details

For these experiments, I have been using a Panasonic NV-GS60 camera weighing a total of 600mg (1.3lbs) with the large battery attached. The whole system weighs about 3lbs. I have positioned the gimbal some distance below the camera to maximise the inertial effect of the camera's mass.The moment of inertia experienced at the gimbal centre is determined by the square of the distance to any mass beyond that point.


The dimensions of the stabilizer against a 5cm grid


Below the camera platform, separated by spacers, is a slotted aluminium plate to which the gimbal housing attaches, allowing the gimbal to be positioned for front to rear balance adjustment.


 


Static Balance


A number of holes in the top plate accept the standard 1/4" camera mounting screw


The gimbal housing can be slid along a channel, to set front to back balance.


Above, steel washers act as counterweights mounted at the front of the counterbalance tube. These are finished with with plastic bottle tops. They are eccentrically mounted, and are turned to adjust roll balance.
Below, the counterweights at the end of the tube are not adjustable, except that, like the front ones, the number of washers can be increased or reduced to adjust  the weighting below the gimbal.



A small lead weight can be slid forward or back along a plastic channel, to fine trim the front to rear balance, A little crude, but effective.


July 2009, I refined the roll balance adjustment with a threaded weighted wheel on a 4mm threaded length. I made the wheel from the outer race of a ball bearing, filled with lead, sandwiched between two metal discs.


 

 

Dynamic balancing of asymmetrically arranged masses

The orange dots indicate the principle centres of mass of the camera and the counterweights. The diagram, right, excludes the mass of the stabiliser framework, although it is not insignificant.

While panning, the centrifugal forces of m1, m2 and m3 need  to be balanced, otherwise  they can produce tilting effects. The vertical distance from the horizontal axis is significant in in this respect. In addition to this, an unbalanced system may experience a tilt or roll force when beginning or ending a fast pan.


Aerodynamics. July 2009

With the stabilizer so finely balanced, and the gimbal so low in friction, even a light breeze can cause instability. The main problem is a side wind, and the modifications shown below are quite effective at balancing the aerodynamics.


A practical design for an aerodynamic fin, placed behind the camera. This can be removed easily or swung to the side.
Below, A small vertically aligned fin positioned at the bottom counterweight. The material is 0.7mm plastic.


The stabiliser with a variable friction panning ring and gimbal #5