2.1.5. The Smart Navigation Manager (SNM)

This manager is a distributed software application responsible for driving the autonomous robot and coordinating all other modules and systems. The SNM is split into (i) the smart operation manager and (ii) the central manager, which also includes the human–machine interface (HMI).

#### Smart Operation Manager (SoM)

The smart operation manager is a human–computer interaction module that can acquire, process, and deliver information based on computer algorithms and is devoted to assisting farmers in making accurate, evidence-based decisions. The SoM is specialized for laser weeding technology, the tool selected for this study.

Data management is performed through the Internet using FIWARE. Data access control is provided via a virtual private network (VPN) to secure data transfer to/from the cloud. The visual dashboard will also be available on the HMI for field operations. Through the dashboard, the operator will also interact with the robot.

The smart operation manager is allocated in the cloud. It contains the global mission planner and supervisor, the map builder, and the module for managing the IoT and cloud computing system (see Figures 3 and 5). The hardware of the SoM relies on a cluster of 10 servers.

**Figure 5.** Cloud computing modules/containers.

(a) Global Mission Planner

A planner is a software tool responsible for computing the trajectories of the vehicle and an a priori known treatment map. The planner obtains some types of information from the Internet, including the following:


Regarding robot location, two types of systems are envisaged, as follows:

	- - Relative location based on RGB and ToF cameras, LIDAR, and IoT sensors: These methods are based on different techniques for navigation in the field and navigation on the farm, such as hybrid topological maps, semantic localization and mapping, and identification/detection of natural and artificial elements (crops, trees, people, vehicles, etc.) through machine learning techniques.

A supervisor is a computational tool responsible for overseeing and monitoring the execution of the mission plan while helping the farmer (operator) manage potential failures. Most supervisor systems are designed around two actions: fault detection and fault diagnosis. The supervisor executes the following actions:


A map builder is an application used to convert maps based on GeoJSON into FIWARE entities. Its main function is to support farmers in using the robotic system in a simple, reliable, and robust way by giving the robot enough information a priori (e.g., farm schema and boundaries, field locations and shapes, crop types, and status). This module takes advantage of the data models created by the FIWARE community to represent the farm and other environments digitally, where they have been conditioned to be adapted to robotic systems and especially oriented to navigation [12]. The design of the Map Builder allows the user to accomplish the following:


This conversion makes it easier to connect the robot to the cloud by standardizing data. These data, after processing, constitute a source for the design of processes with the robot, and its storage and subsequent analysis can provide forecasts of future events in the field or behavior of the robot.

(d) IoT System

This study integrates an IoT sensor network to collect data from the following:

	- - Two multispectral cameras (IoT-F1 and IoT-F2) placed at the boundary of cropped areas to obtain hourly pictures of crops.
	- - A weather station (IoT-F3) to measure precipitation, air temperature (Ta), relative humidity (RH), radiation, and wind.
	- - Three soil multi-depth probes (IoT-F4) for acquiring moisture (Ts) data and three respiration probes (IoT-F5) to measure CO2 and H2O.

Every one of these components or nodes exchanges messages with the Message Queuing Telemetry Transport (MQTT) protocol, carrying JavaScript Object Notation (JSON) serialized information from node sensors/cameras interpreted as the entity. While metering nodes (weather, soil probe, and respirometer) communicate by MQTT messages, camera nodes have to transmit images (maximum of 100 pictures/day for periodic snapshots of the area or alarms), and the use of FTP made a wide-band networking solution, such as WiFi, mandatory instead of narrowband solutions.
