Drives and Controls Magazine
Home
Menu

3D camera system could revolutionise safety technology

01 January, 2007

3D camera system could revolutionise safety technology

Pilz and DaimlerChrysler have collaborated to develop a three-dimensional safety technology that, they predict, will change the way we monitor and protect machinery. The SafetyEye system, which made its debut at the recent SPS/IPC/Drives show in Germany, is based on an array of three cameras that look down at an installation and detect any movements of the machinery or personnel in 3D. The images are analysed by a PC and if a potentially dangerous situation arises, the PC triggers a safety control system to take the appropriate protective action.

The claimed attractions of the technology include:

the ability to operate machinery safely without restrictive physical barriers;

minimising the possibility of over-riding, or tampering with, the safety system; and

the ability to combine warning and detection zones in complex 3D arrangements that are defined on the PC and can be altered easily, if needed.

The system`s potential applications range from guarding robots, packaging equipment and machine tools, to providing access protection for buildings and monitoring museum exhibits.

"Camera-based image processing will revolutionise optical sensor technology," predicts Pilz`s managing partner, Renate Pilz, "and not only in the industrial sector."

Violating a detection zone will not automatically lead to an emergency stop. The PC can determine how long it would take the moving machinery to reach a person who has entered the zone and, if there is enough time, it can slow the machinery down and warn the intruder. If the person then leaves the zone, the machinery can return to its normal movements, minimising disruption. Only if the person enters a danger zone, will a full emergency stop be implemented.

Pilz says that the new system will take a few hours to install and configure, compared to the day or more it can take to set up and check conventional protective devices. Robot installations, for example, often require a complex combination of safety fences, 2D light grids, laser scanners and limit switches. And when danger is sensed, the robot is brought to an immediate emergency stop, and can be time-consuming to restart.

Researchers at Pilz and DaimlerChrysler had been working independently on similar ideas which they then combined to produce the SafetyEye. DaimlerChrysler contributed the sophisticated 3D image-processing algorithms used to track objects, while Pilz adapted these algorithms for industrial use, and developed the practical camera-based safety system.

At least one other German safety specialist is known to be developing a similar 3D camera system.