A Standardized Open Platform Is Key to the Future of Smart Lighting System Design

A great number of companies like Philips and Osram have spent the last few years or so introducing connected lighting solutions, which are proving to be defining points in the evolution of LED lighting. However, for the lighting industry to continue to grow quickly within the ‘smart’ space, two factors are essential. First, the industry must move towards a standardized and interoperable open platform for most lighting control, and secondly, manufacturers must not overlook the cost of transitioning from traditional to digital lighting, and continue to drive efficiencies wherever possible.

The reason these factors are so important is because of smartphones. Traditionally, we have controlled lighting using switches, sensors and wall controllers that have been optimized for traditional lighting or low-level digital lighting in its early stages. However, people increasingly want to monitor the status of remote devices and control them with smartphones, anytime and anywhere.

The Importance of Smartphone Control

The importance of smartphones and other mobile devices is undoubtedly going to grow over time. These technologies have already become the control hub for our everyday lives, enabling us to work on the go and manage our social lives through social media. Lighting has become just one other part of our lives we can now control through our mobile devices.

How Smartphones Connect to Lighting

There are three different ‘tiers’ of connectivity (C1, C2 and C3), which define how smartphones can connect to lighting. The following explanations of each tier are based mainly on Bluetooth low energy (BLE) technology because of its tremendous potential and the strong reception that it has received throughout the industry.

But before getting on to the three tiers, it’s important to consider that traditional legacy lighting (C0) is generally controlled by a Triac or 0–10V dimmer, which gives the control signal to the driver of the LED module in each luminaire.

Within the first tier (C1), a dedicated controller can be added to the existing driver with a BLE-equipped sensor or switch on top of the C0 to allow smartphones to directly control the lighting without the need for a cloud server. In this C1 mode, multiple smartphone controls can enable users to share lighting control with one another.

The second tier (C2) adds the cloud into the mix, which means that users can record data on their lighting, for example, which lights are on at which time, how many lights are on, how much energy they’re using and more. The data that is generated can easily be monetized on a subscription basis.

And for the third and final tier (C3), a Wi-Fi/BLE bridge can be added to enable people to control their lighting through the cloud within the BLE mesh range. This type of setup enables people to confirm the status of their lighting or configure the settings at any time and from any place, remotely, or to set up the most desirable configuration in a smart space.

Figure 1: Three levels of lighting control using smartphones

How Connectivity Made Smartphones the Hub of Smart Lighting

There are several reasons why each of the three tiers of smartphone connectivity is becoming more prevalent within lighting control. The first reason is the evolution of protocols, namely Bluetooth, which can now accommodate smart technology through Bluetooth low energy (BLE), as mentioned before. BLE is quite different from ZigBee, which does not support direct control with smartphones, but is at the center of much IoT activity today, especially at the end node. However, BLE can support mesh technology together with direct control for IoT applications, which is hugely important for high-density end-node applications such as smart homes.

Therefore, the standardization of the likes of DALI, ZigBee and Bluetooth is already underway because of their vital role as core connecting methodologies for lighting networks, sensor networks and wireless phone networks. Most upcoming solutions, therefore, will be based on standardized hardware and firmware so that all players in the digital lighting industry can take part in the development of viable end-to-end solutions. Towards the second half of 2017, most new smart lighting products will be based on DALI 2.0, ZigBee 3.0 and Bluetooth 5.0.

The second reason why smartphones have been able to become control hubs for lighting is because of the improvement and prevalence of mobile networks, which have progressed from 2G to 3G and 4G, LTE, and improvements to Wi-Fi networks. These improvements ensure that smartphones can easily connect to the cloud so users can control their lighting in real time from any location. In terms of security and flexibility in the use of information services, smartphone control will be more widely developed for personalized service on demand, for example healthcare services, which will make the identification through password or biometrics secure while payment process will be much easier with high security.

The Evolution of Smart Lighting

To understand what’s next in the smart lighting industry, some historical context is needed.

The three tiers of connectivity sit within the second generation of digital lighting, which is happening over the next 12 months. The first generation started over a decade ago, with major lighting manufacturers and control system companies developing several proprietary solutions for increasing energy savings through centralized control, based on wired or wireless connectivity. The primary purpose of these first-generation solutions has been to build a lighting network that focuses on ‘connecting’ light. But being the first generation of digital lighting, these solutions are inherently not scalable or sufficiently interoperable with evolving network technologies such as advanced sensor networks, next-generation phone networks, PANs (personal area networks) and BANs (body area networks).

The purpose of such second-generation solutions has naturally been to standardize communication protocols and reduce the pain of commissioning and pairing, where smartphones serve as the primary smart device. In addition, the convergence of sensor and actuator networks (SANs) has created another valuable approach to enhancing the augmented network. And as discussed before, ZigBee and Bluetooth smart technology are key solutions for driving this new generation of digital lighting.

However, the ultimate goal of digital lighting is to develop a hub for the IoT (Internet of Things) that delivers additional network capabilities to PANs/BANs - the third generation of smart lighting. This trend will also lead to a shift in the smart lighting network infrastructure to embrace personalization services like healthcare, as mentioned earlier. This third generation of digital lighting will require an IP address for every node and end-to-end security architectures that can secure personal data with hardware, firmware, and software. The essence of human-centric illumination arises from the physical and biological nature of light, and will be further enhanced when coupled with CCT-tunable and color-tunable LED technology.

Figure 2: The digital lighting transformation

An Open Platform as Key to Success

The answer to making everything above a reality is not for LED manufacturers to build entire proprietary connected lighting solutions due to the high cost involved and subsequent high purchase cost for consumers. In other words, the benefits of connected lighting do not outweigh the costs at this time. So, to drive the cost down, the LED industry must look towards a simple, open platform standard, upon which manufacturers can build their own smart lighting solutions. With the inevitable greater cost savings and increased opportunity for seamless integration, lighting device manufacturers can freely design LED lighting systems based on an open standard platform, and then enhance newly installed systems at their discretion. In addition, human-centric lighting should be built on the same platform, allowing for more sophisticated spectrum control and additional network devices in PANs and BANs.

Figure 3: Seamless options for a step-by-step approach to C1 control

Figure 4: BLE-enabled solution and BLE–ZigBee combo solution in sequence

Figure 5: Step-by-step solutions with clear market relevance

Figure 6: Examples for future-proof products that support different communication standards: in this case Samsung´s SLM series supporting DALI2.0/ BLE5.0/ZigBee3.0

Upon the open platform, manufacturers should consider trying some examples of seamless smart lighting to reduce decision-maker resistance and accelerate widespread adoption of smart lighting, as described in Figure 3. In the US, LED lighting manufacturers can install dimmable drivers for improved LED lighting or continue the use of legacy dimmers like Triac or 0-10V. With existing LED lighting systems, a BLE-enabled dimmer or BLE-enabled smart dimmer can be added to replace a Triac/0-10V dimmer. This will allow smartphones to incorporate much more flexible use of remote control technology in a residential space. Similarly, the same technology can be applied to switches and sensors in converting most existing components to smart components, while keeping some in their legacy designs if desired. With a backward-compatible smart driver, the existing controller can be matched to a new CCT tunable driver. Furthermore, LED modules, drivers and controllers can be consolidated into a single board (or smart engine called an “S-engine”), to reduce cost to an acceptable level.

A step-by-step approach to seamless connectivity will be based on BLE-enabled solutions or the use of a BLE–ZigBee “combo” solution. By using a BLE–ZigBee combo monolithic solution (available during the second half of 2017), a simple, cost-effective, approach can be easily adopted.

Overall, the advantages for lighting manufacturers in choosing digital lighting are very compelling. To illustrate this visually, the key benefits of each step toward smart digital lighting are shown in Figure 5. Adding Bluetooth to an existing Triac/0–10V architecture requires some increase in cost, but this will be less expensive than adding smart features to existing dimmers. There’s also the opportunity to save more energy - add BLE to switches and sensors, and analyze the conditions for using smarter controls, while maintaining code compliance.

In addition, the initial investment can become even more cost-efficient by enabling multiple phone controls over any home appliance, especially useful when the controlling device is in a remote-control mode.

Beyond the above step-by-step options, new multifaceted solutions will support the latest control standards DALI 2.0, BLE 5.0 (mesh) and ZigBee 3.0. Furthermore, 2ch 0-10V dimming will be available for white color-tunable applications, and include power metering for improved energy management.

Concluding Remarks

The driving forces for smart and human-centric lighting solutions have been carefully evaluated here, as well as how to accelerate their adoption beyond the potential hurdles that have been discussed. Combining a Bluetooth smart approach (or Bluetooth low energy) with an optimized mesh and seamless end-to-end control options will likely be the most efficient way to transition from connected to human-centric lighting, via smart lighting. To do so, a seamless solution based on standardized DALI, ZigBee and BLE protocol currently seems to be the best and most promising approach.

Encouraging lighting manufacturers to embrace this approach is the key to a prosperous smart lighting era. The early digitalization of LED lighting will be first realized this year based on a seamless options approach. Moreover, DALI, ZigBee and Bluetooth standardization schedules prior to May 2017 will be consistent with this important shift, and the next generation of end-to-end solutions can be expected to accelerate the transition from smart to human-centric lighting in the second half of the year.