MECS-CROP (Micro Environment and Canopy Sensor, CROP version) is a multi-parameter sensor specifically developed for the characterization of the vegetation canopy and of the micro-environment of open field crops (tomatoes, corn, etc.).
MECS-CROP combines a GPS receiver and a series of sensors able to record the following parameters: Canopy Index (CI), ambient temperature, crop temperature, relative humidity.
It records a rich set of data coming from different sub-sensors when passing inside a field to be monitored with the tractor; those data are continuously geo-tagged by means of a GPS receiver, included in the system.
A post-processing software, called MECS-MAPS, transforms the logged data into a set of different maps, that are co-registered and can therefore be displayed overlaid each other.
The most important provided provided maps are:
- CI (Canopy Index): a quantification of the vegetation covering the field, based on computer vision algorithms instead of usual NDVI-derived approaches;
- ST (Surface Temperature): a direct measurement of the surface temperature of the crop/soil surveyed;
- RH (Relative Humidity): direct measurement of the relative humidity of the atmosphere.
The sensor features a special orientation and a wide angle of view that allows covering a swath width of 20+ m transversely with respect to the direction of the tractor. Furthermore, the Canopy Index measurements are not affected by variations of light on plants (presence/absence of clouds, elevation and angle of the sun, shading, etc.).
A second software tool, called PF-VRT, is used to translate the different specific parameter-maps (for example, CI maps) into prescription maps that can be used in VRT activities (for example, variable rate fertilization and irrigation).
SPREADSAT is a spreader which can control and distribute fertilizers according to a georeferenced distribution map.
Already used in row crops like vineyards and orchards, it has been adapted for the specific purposes of the TOMRES project, with the following requirements:
- use among lines of tomatoes in open fields;
- continuous calibration and control of the spreading;
- ease of use and adaptability of the whole system.
Regarding the fertilizer spreading option, three types of distribution are available, always with an electronic control: spreading with fan, localised underground distribution, localised distribution with pipes. Due to the geometrical conformation of tomato lines, the most profitable distribution is the one with pipes; therefore, the needed adaptations have been implemented accordingly to this choice.
In order to have full control of the right instantaneous spreading amount, a weighing system based on three load cell has been implemented: it allows an automatic calibration of the quantity of fertilizer that is going to be distributed instantaneously. A first calibration is automatically set at the beginning of the distribution, and it is later kept under control continuously during the distribution, so that it can guaranteed that exactly the requested amount of product is actually released in the field instant by instant.
Regarding ease of use and adaptability of the whole system, two additional supports with wheels have been added in the back of the spreader: this can guarantee better chances to use the implement with small tractors, too.
HYDROSAT is an irrigation hose reel with sprinkler which can control and distribute water according to a georeferenced irrigation map.
Already used in open field crops like corn, wheat, tomato and many others, HYDROSAT has been adapted for the specific purposes of the TOMRES project.
The implement comes from an adaptation of a standard Casella hose reel that has been upgraded in order to be controlled by a variable rate irrigation logic, simply obtained by modulating the trolley rewinding speed according to the VRT prescription map. A proper computer regulates the speed through an electric motor which opens and closes the oil flow in the hydraulic unit which is coupled with the hydraulic motor and the planetary gear box.
The computer receives the instantaneous water amounts from an additional upgraded VRT electronic component which works by using the irrigation prescription maps and the positioning information coming from a GPS receiver hosted on the trolley, so that the irrigation map sets and fixes the rewinding speed of the sprinkler.
Regarding the type of sprinkler, it is currently a mechanical sprinkler, that works with the same number of repetitions for left and right sides of the irrigation task. As a future upgrade, Casella plans to integrate into HYDROSAT an electronic sprinkler, which allows to set 4 different angles of irrigation for the different sectors. The user can set/change the angles also by means of a common smartphone. Actually this system is still in testing phase.