Using AeroHead Controller data

This describes how to use AeroHead Controller to receive data which comes from the AeroHead console.

THE AEROHEAD
is a lightweight, three axis digital remote head  featuring continuous three axis movement. It is designed with remote cranes in mind. More information on the AeroHead can be found by following this link. The AeroHead is capable of recording and playing back camera moves. One can download moves from the console, or record the moves directly to a computer via a serial connection, using AeroHead Controller.

Up to 10 axes of recordable data

By itself, the AeroHead has three record-and-play axes: Pan, Tilt, and Roll The AeroHead can be mounted on an encoded TechnoCrane for additional recordable axes: Boom Tilt, Boom Swing, Boom length, and Dolly. The AeroHead can also be used in conjunction with a Preston Fi+Z Control, for record-and-play of Focus, Iris, and Zoom. The AreoHead controller can record the movements on all of these ten axes. The AeroHead can also play back six of these axes (The TechnoCrane is not a Motion Control rig, so it's movement can be recorded, but not played back.)

AeroHead Controller software

AeroHead Controller is software runs on a PC under Windows 2000 or Windows XP, and uses serial ports for communication. It is used to record data coming from the AeroHead, the TechnoCrane, and the Preston Fi+Z control. It converts raw hexidecimal data coming from the AeroHead console into real-world units of inches and angular degrees. Data comes from the AeroHead console to AeroHead Controller via a proprietary format which is subject to change. AeroHead Controller converts and records the data; it also streams the converted data to another computer via a second serial port. This is to enable CG systems to follow the movement of the camera in real-time.

The AeroHead Controller "Boom Scaling" menu allows calibration of raw data to real-world units. The AeroHead itself is already calibrated, but the TechnoCrane needs to be calibrated after each time it is set up. Note that all linear measurements are in inches, and all angular measurements are in degrees.

6 virtual axes

AeroHead Controller computes virtual axis data from raw axes data. This converted data represents the world-space position and orientation of a camera mounted on an AeroHead. AeroHead Contoller has a pre-defined understanding of the physical geometry of the AeroHead and the TechnoCrane, and uses forward kinematics to compute this position. Virtual data is recorded and/or streamed from AeroHead Controller.

Connection Diagram

The AeroHead console sends axis data out through an RS-232 serial connection to a PC (Windows 2000 or newer) running AeroHead Controller. The software optionally sends converted data out through a separate serial port to another system. The serial connections are configurable in the Setup->Com Port pulldown menu of AeroHead Controller.

Typical AeroHead Setups for recording move data

(Note that some are one-way and others are two-way connections)

(click for a larger image)

Data Format

Data coming from AeroHead Controller is ASCII text. Each frame of data is represented by a series of numbers separated by a space and ending with a new-line character (ASCII code 10 (decimal)). Use the "Stream Out" menu of AeroHead Contoller to set which axes are sent out. You can stream out just the 6 virtual axes, or just the 10 individual axes, or all 16 axes. Frames of data are sent at a fixed rate of 24 fps. The baud rate for this has been tested successfully at 115,200bps.

Links for further reference

TechnoCrane specifications: http://www.technocrane.net/

Preston Fi+Z control: http://www.prestoncinema.com/index.html

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