MAIA WV – the multispectral camera

MAIA is the multispectral camera that permits the simultaneous acquisition of high resolution images at various wavelenght intervals in VIS/NIR electromagnetic spectrum regions. It is designed to be employed on board the UAV systems or on board aircrafts, and it finds several applications on board terrestrial rovers too, for precision agriculture, classification of crops, classification of materials on soil, environmental monitoring, dumps monitoring.

MAIA WV is the multispectral camera equipped with the same wavelenght intervals of the DigitalGlobe WorldView-2 satellite.

WorldView-2 is a commercial Earth observation satellite owned by DigitalGlobe. WorldView-2 provides eight-band multispectral imagery with 1.84 m resolution, in support of services such as forest monitoring, land cover changes detection, and natural disaster management.

Now, you can compare satellite data with high-resolution maps obtained through a multispectral survey conducted with MAIA WV-2, the proper instrument for your multispectral survey. 

MAIA is entirely developed in Italy by SAL EngineeringEoptis and Fondazione Bruno Kessler.

MAIA WV is based on an array of 9 sensors (1 RGB and 8 monochrome with relative band-pass filters) to detect multispectral imagery in the VIS-NIR spectrum from 390 nm to 950 nm. MAIA WV is the most advanced broadband multispectral camera fro RPAS, aircrafts, terrestrial rovers available today, with bands in Coastal and Blue spectrum region. 

 MAIA WV     13 500 €  VAT excl.

 

Architecture and interfaces

 

Applications of multispectral survey

Main applications of the multispectral survey conducted with MAIA concern the following fields of interest:

Agriculture and terrain survey

  • precision agriculture
  • precision viticulture
  • vegetation indexes mapping
  • plant species recognition
  • biomass mapping
  • monitoring of health conditions of crops and plants

Industry

  • detection of  chemical dumpings
  • monitoring of industrial plants
  • monitoring of landfills
  • detection of non-authorized dumps
  • detection and classification of materials in terrains and structures

Environmental monitoring

  • detection of pollutant spilling and waste recognition
  • classification of terrains and chemical-physical characterization

Geology

  • detection of paleochannels
  • detection of typology of soils, geological characterization and mapping

 

Optics

CMOS sensors settled in MAIA have resolution of 1.2 Mpixel each, and present excellent characteristics in terms of sensitivity.

Each sensor is global shutter and shoot simultaneously: it follows that it is not necessary to stabilize the shot with gimbal, which is indispensable with roling shutter sensors to avoid distorsions, crawling and blurring pixels in the images.

The high quality and the radiometric validity of data obtained with MAIA are then guaranteed even during high speed flghts.

Thanks to a web panel easily accessible through Wifi and Ethernet, MAIA permits a fine regulation of all parameters concerning the acquisition activities, from exposure time of each sensor to shot frequency. Automatic configurations are available for standard operations.

Each camera is designed to have a series of specific band-pass filters but, on request, it can be equipped with customized filters. Main filter-set are those related to MAIA WV and MAIA S2

MAIA WV is based on an array of 9 sensors with the following characteristics:

  • 1 RGB sensor (RBG Bayer pattern)
  • 8 mono-chromatic sensor with sensitivity in VIS-NIR range from 390 nm to 950 nm

Each sensor has 1280x960 pixels and the dimension of each pixel is 3.75 μm x 3.75 μm.

Mono-chromatic sensors are matched with a bandpass filter based on the intervals as follows:

SensorStart WL(nm)Stop WL (nm)CWL (nm)FWHM (nm)Color
S1395450422.555PURPLE
S2455520487.565BLUE
S352557555050GREEN
S4580625602.545ORANGE
 63069066060RED
S670574572540RED EDGE
S775082078570NIR 1
S8825950887.5125NIR 2
S9----RGB

 

Each sensor has fixed focus lens with the following characteristics:

  • Nominal focal lenght: 7.5 mm
  • Aperture f/#2.8
  • FOV 35° HFOV; 26° VFOV 43° DFOV

Lens are adjusted with focus in laboratory, with no possibility of intervention by the user.

Each optics of every produced MAIA is calibrated in laboratory and for each camera the Calibration Certificate is available, with the following parameters:
- calibrated Focal Length
- position of Principal Point
- distortion lens parameters
Calibration and certificate is carried out by 3DOM group - 3D Optical Metrology of FBK - Fondazione Bruno Kessler in their laboratories.

For the survey operations, the Ground Sample Distance (GSD) and the Field of View (FOV), depending on the Altitude above Ground Level (AGL), are shown in the following table, that also shows the available max speed of the aircraft to acquire images with no motion blur, considering an acceptable pixel blurring and crawling lower than the size of the pixel. The maximum speed of the aircraft depends on images overlap and on shot frequency.

AGL
(m)
GSD
(mm/pixel)
FOV
(m2)

Max UAV speed

with 10 ms exposure time

(m/s) – (km/h)

Max UAV speed

with 1 ms exposure time

(m/s) – (km/h)

502330 x 232.3 – 8.423 – 84
753545 x 343.5 – 12.735 – 127
1004760 x 454.7 – 16.947 – 169
1507090 x 687.0 – 25.370 – 253
20094120 x 909.4 – 33.894 – 338
300141180 x 13514.1 – 50.6141 – 506
400188240 x 18018.8 – 67.5188 – 675


Devices and connectors

Via Wifi or via GigaEthernet port, users can interface with MAIA WV to configure parameters, to visualize in real-time images during the acquisition and to download the already saved ones. For these purposes there are several interfaces: a keyboard, a powerful web panel, two inputs for radiolink receivers.

Web access is available both through a high-speed GigaEthernet connection, and through Wifi connection for operation directly on the field.

MAIA can interface with various devices that can integrate embedded data into the images:

  • GNSS receiver to geotag images
  • radio transmitter that send images to the operator and give him feedback about mission and data acquisition
  • radio receiver for radio remote control of the camera
  • connector for gimbal stabiliser, that takes advantage of the IMU onboard, keeping bearing and orientation
  • other devices that need signal at the moment of the shot
  • ILS - Irradiant Light Sensor

 

Images

Images are stored in an internal SSD solid memory that is mechanics-free, then it guarantees long term high reliability. Memory capacity can guarantee more than 10000 images. RAW files until 12 bit, that concentrate a large quantity of information, are supported.

Along with the camera, an image processing software will be provided for geometric correction, correction of radial distorsion, coregistration and radiometric correction of the RAW multispectral images acquired with MAIA WV, with tools for indexes calculation and for band combinations.

 

With MAIA - MultiCam Stitcher Pro software, you could create multi-layer tiffs, multichannel tiffs, create view with combination of bands, create index images and preview the raw dataset just acquired.

You can correct the geometrical distortion of images, get the coregistration pixel-pixel for each band, correct the radiometrical informations within the pixels.

Thanks to this software, you can generate the specific kind of dataset that could be useful for your purpose: photogrammetric processing, single shot analysis, indexes or band combination mapping.

This image processing software of MAIA WV images is jointly developed with the cooperation of 3DOM - 3D Optical Metrology - Fondazione Bruno Kessler (FBK) based in Trento (IT).

 

 

Technical features

 

Sensors

1 RBG Bayer pattern Sensor
8 CMOS Mono-Chromatic sensors with Bandpass filters
Array 3x3 – Centre to centre: 25 mm
Resolution: 1.2Mpixel (1280x960) each
Type: Global Shutter
Pixel size: 3.75 μm x 3.75 μm

Optics

Sensitivity interval VIS-NIR: 390 nm to 950 nm

Sensor

Wavelenght (nm)

S1

395-450

S2

455-520

S3

525-575

S4

580-625

S5

630-390

S6

705-745

S7

773-793

S8

750-820

S9

825-950

Lens Fixed focus
Focal lenght: 7.5 mm
Open f/#2.8
FOV: 35° HFOV; 26° VFOV; 43° DFOV

Exposure

Type: Manual / Automatic / Automatic based on Max Time Exposure
Start simultaneous for each sensor
Exposure Time: 0.1 ms - 50 ms

Typical exposure time: 1ms

Acquisition

Type: Single shot / Continuous with external trigger / Continuous at fixed-time interval
Max frame rate: 3 frames/sec with RAW 10bit and RAW 12bit; 6 frames/s with RAW 8bit

File format

RAW 8 bit
RAW 10 bit
RAW 12 bit

Memory

Type: Internal SSD
Capacity: 120GB (standard); 250GB; 500GB (on demand)
Image size: 21.2 MByte in RAW10 and RAW12
11.8 MByte in RAW8

Embedded data

Exposure time for each sensor.
Timestamp at the shot time.
Time, position, speed, fix GNSS.