The course of this project demonstrates the value of the reference implementation approach: it allows a prototype to be built with a relatively small investment of time and effort, followed by an efficient transition to a commercially viable solution. Using a precompiled OS as well as RPMs helps to eliminate unnecessary downloads, having to customize the OS, and identifying libraries necessary to bring a project to life.

This project was devised to contribute to innovations around solutions for similar use cases being produced and marketed. While this project was designed to provide only basic functionality, its design is flexible and extensible enough that a variety of features could be added. In particular, the project could be expanded in the future to include web connectivity, cloud capabilities, remote monitoring, and other components.

In the project’s earliest stages, the team listed potential features for the prototype and the product. A sample of these included rear-door status (open or closed), temperature of the trailer, alarms based on the state of the door and temperature, an online application to view data, and in-cab monitoring of information. To demonstrate the viability of creating a robust solution while maintaining simplicity and low cost, the team elected to limit the bill of materials for the prototype phase to just the contents of the Grove IoT Commercial Developer Kit.

To allow for separation of duties and efficient progress, the team divided the solution into three primary areas of effort:

• User interface (UI). Part of the team began working on the actual production UI layout and design, looking ahead to the production stages of the project.
• Application business logic. Part of the team began working on the logic for the prototype application, while also recognizing that changes would be needed as the project progressed toward the commercial solution.
• Prototype sensor solution. Part of the team began to create the configuration of sensors for the solution, utilizing the UPM*/MRAA* libraries for rapid development.

This approach of separating the project into discrete segments allowed the team to progress through the prototype phase more rapidly than otherwise, taking best advantages of skill sets available within the team. In particular, while the user interface was not strictly required in the early phases of the project, it was expected to require the most development time of the three areas listed above. Therefore, beginning it as early as possible allowed for it to be well underway by the time it was needed later in the project.

In terms of the application logic, the team was able to look ahead to the expected final functional prototype and make decisions in the early prototype process looking to the future. Overall, the team expected the operation of the door sensor to be relatively simple, allowing greater attention to the proper utilization of a temperature sensor on a small and then commercial scale.

By utilizing the sensors in the Grove Starter Kit Plus, we were able to rapidly create a prototype with a functional sensor environment that the UI team could work with. This approach enabled layout and design elements to come to life quickly and provided a future framework for the final functional use case. The prototype configuration, with the Intel NUC, Arduino 101 board, and sensors, is illustrated in Figure 3. The bill of materials is given in Table 2.

Table 2. Connected transportation prototype components

The use case was built and displayed through an administration application to support the following scenario:

1. Press button to start the use case (simulating opening the door):

   a.    Sets threshold ambient temperature +5 degrees.
   b.    Solid red LED lights up in cab.
   c.    LCD displays current temperature and door status (open), as shown in Figure 4.

   

    

2.  Touch temperature sensor raises ambient room temperature by five degrees:

   a.    Buzzer sounds.
   b.    Red LED blinks continuously.
   c.    LCD turns red and displays actual temperature and door status (open), as shown in Figure 5.

   

    

3. Touch sensor to acknowledge alert (buzzer turns off).
4. Press button to close the door:

   a.    Red LED continues to blink until temperature passes below threshold.
   b.    LCD displays temperature and door status (closed).
   c.    When temperature passes below threshold, blinking red LED turns off, solid green LED lights up, and LCD turns green.
   d.    LCD displays temperature and door status (closed).

With an operational prototype based on the Intel IoT Developer Kit and Grove IoT Commercial Developer Kit, it was necessary to determine how to proceed to create a commercial solution. Table 3 outlines how the components used in the prototype phase could be replaced with a production solution.

Table 3. Components in the prototype versus production solution

In addition, there are many commercial gateways available, with design differences making them suited to various industries and use cases. A key consideration for this project was a broad range of I/O options, to support both current and future functionality, specifically for connecting sensors to provide a data feed.

An Intel IoT Gateway was chosen as the gateway device for the product portion of this project, as shown in Figure 8. The processing power and I/O functions were deemed sufficient for the presented commercial usage.

A wired Modbus temperature sensor was chosen to provide a reliable connection to obtain temperature readings every several seconds. All communications on devices were performed via direct wiring or via Ethernet. Standard MRAA/UPM libraries were maintained throughout the process without any modifications.

The gateway acts as a web server, storing data as well as making calls to the temperature sensor to keep the data fresh.  The Java UPM Library uses libmodbus to read and send periodic updates from the Comet* temperature sensor to the Tomcat* web server.