Integrating Modularity for Mass Customization of IoT Wireless Sensor Systems

As data collection and analysis grows in demand across a diverse spectrum of industries, data is collected from many sensors at different ranges with different quantities and types of data. One general approach taken by commercial firms to integrate wireless sensor data is to develop proprietary "ecosystems" of products; home automation companies like NEST, home security companies like SimpliSafe, and agricultural companies like Davis Instruments each require that customers use their hubs with their peripheral sensors. The work in this paper applies a flipped approach where a heterogeneous set of sensors from a range of suppliers connects to a hub over a variety of wireless protocols. The design of the hub, therefore, needs to easily accommodate a wide range of communication and wireless protocols. The focus of this work is on exploring how modularity can be designed into the architecture of a product to facilitate quick and low-cost customization of the hub to a particular need.This particular work focuses on designing such a hub for various low-power wide-area network (LPWAN) applications. LPWANs are technologies and protocols that have longer ranges and lower power usage than higher bandwidth protocols like Wi-Fi. LPWANs, like LoRa, specialize in applications where many sensors are distributed over larger distances and, due to the small amounts of data they intermittently send, require less power. This modular hub needs to be able to recognize the type of radio connected to it and the type of communication (I2C, SPI, UART) used by the radio. Such recognition will enable variable quantities of different radios to be connected to the hub without significant redesign of the electronics or the firmware. Furthermore, the housing for the hub needs to be sufficiently modular so that any radio could be inserted without requiring a new design. Using custom components in only certain interfaces is central to the electronics design, and such modularity depends heavily on the firmware. With respect to the housing, a key trade-off for integrating modularity is accommodating variability in radios while maintaining ergonomic design. A key consideration in both housing and electronic design is incorporating modularity only where needed, and creating components in-house when necessary.