Seven sensors for smart buildings

Jonathan Catchpole, System Architect for TE Connectivity, highlights the seven most essential sensors for smart home and intelligent buildings. He also takes a closer look at how the AmbiMate sensor module combines these sensors to speed up products to market for developers. 

The intersection of IoT in commercial applications and residential markets is offering a host of new solutions in a fast-growing, multibillion-dollar market.

In our connected world, people want to be able to monitor and manage appliances and systems, such as lighting and heating. They want to have the convenience of being alerted when they’re about to run out of milk at home or achieve energy savings as lights and heating automatically turn on and off as they enter or leave an office or room.

In response to a changing environment, new demand for indoor air quality is also becoming more prevalent - most notably in grade A offices, hospitals and schools. Research has shown that decision-making and focus can improve by adjusting the ventilation in reaction to levels of carbon dioxide (CO₂) and Volatile Organic Compounds (VOCs). Operators of these buildings are, therefore, eager to optimise the environment.

The seven sensors

Only four core and three optional sensors are required to achieve the above functionality in any building. The four primary sensors are ambient light, temperature, Passive Infrared (PIR) and humidity sensors to provide data for control of lighting, blinds and HVAC. Collectively they enable a smart building system to monitor and respond to environmental conditions, natural light levels, and occupancy.

A popular optional sensor is a microphone, which offers developers a secondary occupancy detection method that is helpful when office workers remain stationary for extended periods. The microphone can also monitor noise, to see if a space is continuously above a certain level, or add voice activation for an artificial intelligence bot. As voice search and smart speakers grow in popularity, the latter is a feature that will soon rise to prominence.

An unintended consequence of energy efficiency measures means that air quality is reduced in today’s indoor environments because windows are sealed shut to minimise energy loss, limiting our carbon footprint.

The WELL Building Institute, which takes a holistic approach to health and quality of life in the built environment, asserts that poor ventilation contributes to headache and fatigue. Proper ventilation, in contrast, promotes good health and improves cognitive function. Little surprise then, that the remaining two most popular optional sensors monitor CO₂ and VOC levels respectively for indoor air quality.

A smart building system that can improve air quality can, therefore, boost productivity in schools, hospitals, and other buildings, ensuring better outcomes and better decision-making.

Multi-sensor module for smart buildings

Having spotted an opportunity to integrate the four core sensors for smart building developers and managers, TE introduced the AmbiMate MS4 Multi-Sensor Module as a dedicated sensor device for smart buildings. It provides developers and engineers with a pre-engineered module that includes the core sensors with the option of adding a microphone and/or air quality sensor. The solution reduces the time required to research, source and integrate multiple sensors, thereby reducing time to market and freeing up resources to work on other aspects of smart building system designs.

Electronics developers can plug an AmbiMate module into a host controller like a Raspberry PI or Arduino device and start collecting data within 30 minutes. The module is compatible with the I²C communication protocol.

The sensor module is available as a developer kit and developers can download supporting software from TE.com. The kit provides multiple attachment options, which give developers flexibility to try out alternative mechanical fixing and connection options inside their product housing.

A lens is also available that provides the PIR sensor with a four-metre diameter detection zone for a sensor mounted at a standard 2.8m ceiling height. For developers who are ready to scale up production, the module is also available as a standalone Printed Circuit Board Assembly (PCBA).

Finding favour with professional electronics developers

One developer in Latin American is using the module at the heart of its system to automate air quality management in hospitals and schools. It has thus far created a Minimal Viable Product (MVP) and has the ultimate goal is to export across Latin America to support better clinical and educational outcomes.

In another project, TE is working with technology enabler Arrow Electronics and its Five Years Out innovation team to create an off-the-shelf wireless and battery-powered sensor module called the Sentimate. This product packages the AmbiMate with the latest generation of wireless radios from Silicon Labs to support data transmission via protocols such as Bluetooth 5, Zigbee, Thread and Z-Wave. The idea is that the Sentimate will provide the  experience and insight that will help developers choose their preferred radio modules and sensor components. 

Enthusiasm from makers

BK Hobby from Philadelphia made the AmbiMate MS4 Multi-Sensor module an integral part of his Kube Multisensor, an open-source, open-hardware DIY sensor platform that he has posted on GitHub to inspire other makers. He selected the AmbiMate module because it is a low cost sensor with all the sensors he needed for the project and because he could get it up and running quickly.

Working as a systems engineer in industrial automation, BK worked on the project in his spare time. According to BK Hobby, “the pre-engineered AmbiMate module combines multiple sensors into one simple circuit board with a high level of support in software. It can also be integrated easily with a host product.”

TE is also preparing to launch its own intelligent sensor kit in 2020 in which the AmbiMate will be a central component, alongside a housing design that makers and developers can customise and produce on a 3D printer.