HOW TO REDUCE JITTER OF AIRBORNE CAMERAS

When a police officer in a helicopter is trying to use a camera to read a license plate on a car, it is vital that the image not jitter; otherwise it will be too blurred to read. There is a constant vibration on a helicopter, plus there are g forces introduced by the motion of the helicopter. Normally, these external forces would cause the camera image to jump around. However, if the camera is balanced so its center of gravity is exactly at the center of rotation of the gimbaled mount, then the image settles down - the camera is stabilized.

Why does jitter happen and how to reduce it?

When an external force such as a vibration is applied to a gimbaled camera it creates a moment proportional to the distance between the point of application of the force (which is the center of gravity of the gimbaled assembly) and the axis of the gimbal. This moment creates a force that tends to rotate the camera.

Many airborne cameras are mounted on two-axes or three-axes gimbals. To make the camera immune to vibrations on all axes, the center of gravity of the moving assemblies needs to be located at the intersection of the gimbal axes. Note that it might not always be possible to do so if the axes are not intersecting. Space Electronics developed a method to optimize the balance of the gimbal even in these cases.

How to stabilize an airborne camera? The solution is called gimbal balancing

Space Electronics is the inventor of the gimbal balancing machine and offers the highest sensitivity machines available. These instruments measure the amount of unbalance of the gimbal and allow to calculate the best solution to compensate for it. Stabilizing a camera now requires less than an hour. For more information on the gimbal balance machine please visit our dedicated gimbal balance machine page.