digital video cradle

Digital video cradle

Digital video cradle

Specifications:

3 functions radio control: horizontal, vertical and shutter release

Camera: Olympus Camedia C1 (c-you) electrically released

Powering of the cradle with Camedia C1 batteries

Video feedback with Camedia C1 video output transmitted by 2.4GHz link

Cradle control by the video monitor camcorder of the video cradle

Total weight with camera and pendulum suspension: 390g

Description:

Design objectives were to build a high performance cradle with minimum weight and size. This led to following 2 major choices:

The standard frame used for most cradles is discarded. The cradle is based on a shape where the angle axis is on the bottom of the camera. Mechanical and electronic parts are on the back.

The cradle itself has no battery, but uses Camedia C1 internal power.

Mechanical: it is based on 1mm folded aluminum. Horizontal axis is made with 2 small hinge. Motors are 2 HITEC HS85BBMG servomotors in which mechanical stops have been removed. The vertical axis is directly coupled with the servomotor, whereas the horizontal axis is moved through gears.
Cradle weight without Camedia C1 is only 130g.

Electronics: Radio receiver is a 434MHz FM Radiometrix module. A Microchip PIC16F84 with 10MHz clock controls the motors and the Camedia C1 shutter release. Electronic board contains 2 H bridge to power the servomotors in which all electronic parts have been removed. The cradle is connected to the Camedia C1 through a 5 pins connector: 2 for power supply and 3 for shutter release.

Power supply: The Camedia C1 is internally powered with 2.4V by 2 AA NiMh batteries. A DC/DC circuit converts the 2.4V voltage to 5V voltage to power the PIC16F84, the receiver module and the video transmitter. This DC/DC converter is built with a LTC1300 from LINEAR.

Rear view

Mechanical

Servomotors

Electronics

Radio control: The digital cradle is controlled by the same customized camcorder used for the video cradle. The selection of the cradle is made through a switch on the camcorder. In that way, it is possible to use at the same time both video cradle and digital cradle.

Video: The Camedia C1 video output is connected to the 2.4GHz KERN video transmitter of the cradle with a standard 3.5mm jack connector (see video workshop for details about the KERN micro transmitter). The video picture generated by the Camedia C1 contains the current photo number and the battery indicator. As the Camedia C1 freze the photo on its video output after each release, it is possible to check the true framing, which is very useful.

Radio control &
video monitor

Viewfinder picture