Sensor Grid-EYE Infrared Array

Technology and Evolution in Sensing

Industries are revolutionizing in the field of sensor development. And all this has the purpose of creating and improving devices, to assist in several sectors: personal comfort, medicine, safety and among other areas of interest for sensing.

In recent years, it is common to enter an environment and many devices work without the need for human intervention since the level of automation and applicability of sensors has grown considerably.

Something quite common is walking down a corridor of a building and the lamps trigger automatically from the user's presence. This is done based on the use of infrared (IR) or passive infrared (PIR) sensor.

These sensors have the ability to detect presence through the heat from the infrared radiation emitted by the human body in motion and then trigger the lamp because all objects emit electromagnetic radiation as a function of its temperature above absolute zero.

They have been widely employed for human tracking systems due to their low cost, power consumption, small size, and privacy preservation.

However, these simple sensors will not be able to detect immobile objects, since their detection occurs only for bodies that are in motion.

Another problem is that they lack the ability to inform the direction of any movement within their field of vision. To this end, the need for the development of new technologies to improve and supply these presented problems has arisen.

Thinking of a solution, some time ago Panasonic created a new infrared sensor device with new features and functionalities: the Sensor Grid-EYE Infrared Array, as shown in Figure 1.

Grid Operation - EYE Infrared Array

Among the various motion detection sensors using infrared, Panasonic developed the Grid-Eye using a matrix with 8 x 8 size microelectromechanical PIR sensors (MEMS Technology).

The detection of a target occurs through the reception of infrared waves with length 5 - 12 μm irradiated by the human body to the 64 MEMS thermophiles forming the Grid-EYE sensor.

From the temperature gradient, each thermopile will be sensitized to a different value and form a thermal image (Thermal Image).

This process is represented graphically in Figure 2.

The thermopile array sensors do not just measure the temperature, they are able to measure the temperature gradient.

Through this gradient, it has the ability to measure the direction of movement (up, down, left, right and diagonal), detection of various people and objects moving in various directions, as well as some simple gestures.

Characteristics

The following are some features of the Grid-EYE Infrared Array sensor:

Supply voltage: 3.3 V ± 10% or 5 V ± 10%

Detection distance: 7 m

2D temperature detection with 8 x 8 area (64 elements)

12-bit I²C external interface

Viewing Angle: 60º

Applications

Among the various applications, it is possible to mention the application of the sensor in the area of residential automation, to detect presence and positioning of people in the environment, so that, according to its positioning, allows connecting certain points of illumination, as a way to improve energy efficiency.

In the security monitoring systems, to assess and monitor the positioning of people in certain areas, who should not have access. Another applicability is in the medical field. Through the Grid-EYE, it is possible to monitor the presence, positioning, and immobility of a patient in medical imaging equipment.

The applicability of the Grid-EYE Infrared Array sensor goes far beyond what has already been cited. Its detection power allows to use of the sensor in several applications and it proves to be an element that can boost the development of diverse systems of detection and monitoring.

Acknowledgements

Thank you for reading and PCBWay for offering great electronic boards for the development of electronic projects.

The Silícios Lab thanks UTSOURCE to offer the electronic components for this project.