Visible Light Communication (VLC) is a short-range optical wireless communication technology that has been gaining attention due to its potential to offload heavy data traffic from the congested radio wireless spectrum. At the same time, wireless communications are becoming crucial to smart manufacturing within the scope of Industry 4.0. Industry 4.0 is a developing trend of high-speed data exchange in automation for manufacturing technologies and is referred to as the fourth industrial revolution. This trend requires fast, reliable, low-latency, and cost-effective data transmissions with fast synchronizations to ensure smooth operations for various processes. VLC is capable of providing reliable, low-latency, and secure connections that do not penetrate walls and is immune to electromagnetic interference. As such, this paper aims to show the potential of VLC for industrial wireless applications by examining the latest research work in VLC systems. This work also highlights and classifies challenges that might arise with the applicability of VLC and visible light positioning (VLP) systems in these settings. Given the previous work performed in these areas, and the major ongoing experimental projects looking into the use of VLC systems for industrial applications, the use of VLC and VLP systems for industrial applications shows promising potential.

This letter presents an efficient algorithm for estimating the three-dimensional (3D) location of a photodiode (PD) receiver via visible light positioning. It solely works on measured powers from different light-emitting diode (LED) sources and does not require any prior knowledge of the PD receiver height. It is found that four LEDs are required that are not on the same circle, in order to unambiguously determine the 3D location. The algorithm is optimized towards a minimized calculation time in view of real-time operation on energy-constrained lightweight and mobile devices such as drones.

In this paper, a novel three-dimensional (3D) indoor visible light positioning (VLP) algorithm using the Cayley–Menger determinant (CMD) with a cost function is proposed and experimentally tested to track a drone for industrial applications. The proposed algorithm uses optical received signal strength (RSS) for estimating the drone’s 3D position without prior knowledge of its height. This reduces the need for additional height sensors used in some 3D VLP systems. The performance of the proposed algorithm in terms of positioning error is also compared with a linear least squares (LLS) trilateration algorithm, with and without tilting of the receiver and with multipath reflections. The simulation results show that the proposed algorithm is more accurate and outperforms the LLS algorithm by a median improvement of 21% and is also more robust to the effect of tilting, as well as in the presence of multipath reflections. Furthermore, the proposed algorithm has been experimentally tested and compared with the LLS algorithm in a VLP test bed measuring 4 × 4 × 4.1 m ${}^3$ . The experimental results show that the median errors for LLS are 11.4 cm, while the median errors for CMD are 10.5 cm, which results in an error decrease of 8% when CMD with a cost function is used.

There is a great deal of research in visible light communications (VLC) for a wide range of applications. However, there is a clear gap in VLC uses for industrial applications. The aim of this paper is to investigate the unique challenges that exist in VLC for the industrial environments. A modified Monte-Carlo method is used to investigate the VLC channel characteristics in warehouses. The paper demonstrates the effects of different ceiling heights and illumination levels on the impulse response, signal to noise ratio (SNR) and bit error rates (BER) of VLC in industrial environments. The required illumination levels are investigated using two different commercial lights fixtures offered by OSRAM and Philips intended for industrial settings with different beam angles and output power. The simulation results show that adequate levels of SNR exist under 5.6, 10, and 15 meter ceiling heights for both scenarios. Additionally, the signal fluctuation due to the receiver's mobility is also simulated. The results show a 10.4 dB drop when moving along a selected path under a VLC channel.