video cradle

Multifunction video cradle

Radio control &
video monitor

Specifications:

4 functions radio cradle: horizontal, vertical, shutter release and video transmitter antenna angle

Camera: OLYMPUS mju-II, electrically released

Black and white video monitoring with camcorder viewfinder

Radio control and video feedback monitor "all in one" integrated into the camcorder body

On screen display of the 4 main parameters: altitude, wind speed, video battery voltage and photo number

Display of other control parameters on request: horizontal direction, video antenna angle, temperature, cradle battery voltage, hour and date.

Storage in permanent memory of all parameters of each photo

RS232 port to transfer parameters to a PC computer and to connect a GPS.

434MHz FM up-link for cradle control

2.4GHz FM down-link for video transmission

Cradle total weight with camera and suspension: 840g

Global Positioning System position display option

Cradle description:

In contrast to the radio cradle, the video cradle body stay fixed towards the line. This choice is required by the anemometer sensor that has to stay in the wind.
Electrical link between the body and the mobile part of the cradle is made by a strand of 10 wires winded round the vertical axis.
Mechanics is based on aluminum profile (see mechanic workshop).
Olympus mju-II is electrically released (see cameras).
The angle of the antenna of the 2,4GHz video transmitter is adjustable to optimize the range according the position of the receiver on ground.
The video signal is generated by a mini CMOS high definition camera.
The radio up link is based on 434MHz transmitter and receiver modules and is controlled by a microcontroller PIC16F876 (see electronic workshop).
Electronics and motors are powered with a 6V lithium battery CR-P2/DL223. Video part is powered with 4 standard AA batteries connected to a 5V to 12V DC/DC converter (see video workshop).
The electronic board contains 2 Microchip PIC16F876 microcontrollers and the STV9426 On Screen Display circuit, and performs following tasks:

Reception and decoding of orders coming from ground

Control of 3 servomotors, release of the camera, and selection of video signal (video picture or parameters picture)

Measurement of power supply voltage, temperature, atmospheric pressure and anemometer sensor

On screen display in video picture of main parameters and camera frame

Video signal generation of the parameter picture

Storage in permanent memory of parameters of each photo

RS232 management to save parameters to a PC computer

Control panel description:

All parts necessary to control the cradle are inside a JVC 315S camcorder. All optical, electronic, and mechanical parts have been removed from the camcorder body, except the viewfinder. In the camcorder, we can find:

The 2.4GHz video receiver,

The 434MHz transmitter,

Electronics for push button read, based on a Microchip PIC16F873 microcontroller,

Power generation from the 9.6V battery of the camcorder: 5V for microcontrollers, 8V for the viewfinder and 15V for the 2.4GHz receiver.

Only the 2,4GHz antenna is sticking out of the original camcorder.
The cradle is controlled through original camcorder pushbuttons and switches, which give optimum ergonomics. Full control of the cradle is done with one hand.

Parameters description:

Following data are On Screen Displayed in the picture shown in the camcorder viewfinder: Frame of Olympus mju-II photo Current photo number Cradle altitude Wind speed in km/h Battery voltage of the video part of the cradle	Click to get full size picture
Following data are display on request in a specific picture: Current photo number Cradle altitude Temperature Horizontal and vertical position of the camera, and 2.4GHz transmitter antenna angle Wind speed in km/h and beaufort Voltage of the system batteries: 6V and 4.8V of the cradle, 9.6V of the radio control Hour and date Values of these parameters are stored in a EEPROM which can hold 512 photo records.
Memory content can be displayed in the viewfinder at any moment. All data can be also downloaded through the RS232 port to a computer with VT100 terminal emulation. When outside, I use a Hewlett Packard HP48G pocket calculator, much smaller than a PC (see picture). In this way, it is possible to get the exact release conditions of each photo. RS232 link is also used to set hour and date in the cradle.

Global Positioning System (GPS) position display

The cradle can be connected to a GPS through the RS232 link, and transmits on ground the geographic coordinates of the cradle.
These informations are stored in the GPS as waypoints at each photo release.
After return on ground, data of each photo can be tranferred from GPS to PC computer.

Characteristics:

MAGELLAN GPS 315

On Screen Display of latitude, longitude and absolute altitude in the picture transmitted to the viewfinder

NMEA2.1 GPS standard compatibility

Use of proprietary MAGELLAN protocol to store a waypoint at each photo release

Total weight of the system (GPS 315 + handing + cable): 230g

Click to get
full size picture

Viewfinder picture

Waypoint list

Waypoint data