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In many industrial application domains, such as industry 4.0, logistics, process automation and personalized services, there is a need to operate in a more efficient and less time consuming way. Efficiency studies often involve simulations as a fundamental step to verify and analyze the performance of novel solutions. However, experimental research offers the possibility to validate innovative ideas on real systems and testbeds. To this end, we created a testbed for warehouse automation experiments with mobile AGVs and drones. This enables research on many different aspects such as indoor localization solutions, sensor fusion algorithms, video recognition, assets scanning, autonomous flight, path planning, drone charging, drone construction and materials.

Ultra-wideband (UWB) localization is one of the most promising approaches for indoor localization due to its accurate positioning capabilities, immunity against multipath fading, and excellent resilience against narrowband interference. However, UWB researchers are currently limited by the small amount of feasible open source hardware that is publicly available. We developed a new open source hardware platform, Wi-PoS, for precise UWB localization based on Decawave&rsquo, s DW1000 UWB transceiver with several unique features: support of both long-range sub-GHz and 2.4 GHz back-end communication between nodes, flexible interfacing with external UWB antennas, and an easy implementation of the MAC layer with the Time-Annotated Instruction Set Computer (TAISC) framework. Both hardware and software are open source and all parameters of the UWB ranging can be adjusted, calibrated, and analyzed. This paper explains the main specifications of the hardware platform, illustrates design decisions, and evaluates the performance of the board in terms of range, accuracy, and energy consumption. The accuracy of the ranging system was below 10 cm in an indoor lab environment at distances up to 5 m, and accuracy smaller than 5 cm was obtained at 50 and 75 m in an outdoor environment. A theoretical model was derived for predicting the path loss and the influence of the most important ground reflection. At the same time, the average energy consumption of the hardware was very low with only 81 mA for a tag node and 63 mA for the active anchor nodes, permitting the system to run for several days on a mobile battery pack and allowing easy and fast deployment on sites without an accessible power supply or backbone network. The UWB hardware platform demonstrated flexibility, easy installation, and low power consumption.

Current inventory-taking methods (counting stocks and checking correct placements) in large vertical warehouses are mostly manual, resulting in (i) large personnel costs, (ii) human errors and (iii) incidents due to working at large heights. To remedy this, the use of autonomous indoor drones has been proposed. However, these drones require accurate localization solutions that are easy to (temporarily) install at low costs in large warehouses. To this end, we designed a Ultra-Wideband (UWB) solution that uses infrastructure anchor nodes that do not require any wired backbone and can be battery powered. The resulting system has a theoretical update rate of up to 2892 Hz (assuming no hardware dependent delays). Moreover, the anchor nodes have an average current consumption of only 27 mA (compared to 130 mA of traditional UWB infrastructure nodes). Finally, the system has been experimentally validated and is available as open-source software.

The Internet of Things (IoT) has given rise to different sub-GHz Low Power Area Network (LPWAN) technologies, each having specific characteristics. Today, devices can support multiple LPWAN technologies, picking the best technology depending on application requirements and availability. Realizing such multimodal communication introduces complexity at both the device and network side. In this demo, we show how we can control and manage multimodal LPWA networks by a Virtual Network Operator (VNO) using unified control APIs based on the OMA Lightweight M2M protocol. On top, we demonstrate the use of a single stack across different LPWANs by implementing an adaptation layer between the IP and MAC layer and the feasibility to achieve real multimodal communication.

Indoor positioning systems (IPS) aim to track objects, people or assets with the highest possible accuracy. In literature, it has been shown that among radio-frequency based technologies, ultra-wideband (UWB) is capable of providing em-level accuracy. However, this technology is not yet mature when it comes to large-area coverage and multi-user support. To remedy this, this paper proposes a TDMA protocol for a large scale localization network with numerous simultaneously active users. To this end, a full system was designed that handles the scheduling of the transmissions, the synchronization of the fixed nodes and the roaming of the mobile nodes. Moreover, the performance of the system has been analyzed by simulations using OMNeT++ and INET framework. The simulation was improved with real life experiments and has been used to evaluate full TDMA/TDoA approach. Our solution improves the scalability to 88.3 % effective spectrum usage, compared to only 18.6% when using ALOHA, while mobile nodes are able to roam successfully in 90% of the handovers.

The Internet of Things (IoT) domain is characterized by many applications that require low bandwidth communication over a long range at a low cost and at low power, which has given rise to novel Low Power Wide Area Network (LPWAN) technologies that operate in the sub-GHz domain. Today, these technologies are being adopted in more complex settings and configurations than originally intended. Devices are being equipped with multiple LPWAN radio technologies to satisfy more diverse requirements, connecting to different networks at different times and locations. Further, organizations can have devices with different LPWAN technologies in the field or existing infrastructure might be shared across different organizations. As a consequence, there arises an increasing complexity in managing such multimodal LPWANs and in designing IoT applications on top. We present and validate the concept of a cloud-based virtual LPWA network operator that unifies such multimodal communications and homogenizes the way such heterogeneous private LPWAN deployments are managed by means of distributed OMA Lightweight M2M (LwM2M) containers. In addition, our architecture provides support for the most recent efforts in adopting IPv6 for LPWAN communication.

The increasing elderly population and the shift from acute to chronic illness makes it difficult to care for people in hospitals and rest homes. Moreover, elderly people, if given a choice, want to stay at home as long as possible. In this article, the methodologies to develop a cloud-based semantic system, offering valuable information and knowledge-based services, are presented. The information and services are related to the different personal living hemispheres of the patient, namely the daily care-related needs, the social needs and the daily life assistance. Ontologies are used to facilitate the integration, analysis, aggregation and efficient use of all the available data in the cloud. By using an interdisciplinary research approach, where user researchers, (ontology) engineers, researchers and domain stakeholders are at the forefront, a platform can be developed of great added value for the patients that want to grow old in their own home and for their caregivers.

Home automation devices are becoming increasingly popular in the field of consumer electronics. Various appliances like thermostats, smoke detectors, intelligent lighting systems, etc., have appeared on the market to create a smart home. Vendors have the availability over multiple wireless technologies to connect their products to the smart home and communicate with the user. The most adopted technologies are the ones that can interface directly with a mobile device such as a smartphone or tablet, without the need for an additional gateway. Within this context, Wi-Fi and Bluetooth are the dominant technologies. In this paper we look at home automation devices that have chosen to solely support Bluetooth 4.0 as communication interface. We highlight the downsides of this technology in a home setting and try to mitigate this problem by exploiting the Wi-Fi capabilities of other devices, in particular smartphones. The proposed solution realizes a Wi-Fi bridge on the smartphone that is connected to the Bluetooth device. This enables other smartphone users to connect to the Bluetooth device over the Wi-Fi network, alleviating some of the downsides of the Bluetooth technology.

Smart embedded objects will become an important part of what is called the Internet of Things. Applications often require concurrent interactions with several of these objects and their resources. Existing solutions have several limitations in terms of reliability, flexibility and manageability of such groups of objects. To overcome these limitations we propose an intermediately level of intelligence to easily manipulate a group of resources across multiple smart objects, building upon the Constrained Application Protocol (CoAP). We describe the design of our solution to create and manipulate a group of CoAP resources using a single client request. Furthermore we introduce the concept of profiles for the created groups. The use of profiles allows the client to specify in more detail how the group should behave. We have implemented our solution and demonstrate that it covers the complete group life-cycle, i.e., creation, validation, flexible usage and deletion. Finally, we quantitatively analyze the performance of our solution and compare it against multicast-based CoAP group communication. The results show that our solution improves reliability and flexibility with a trade-off in increased communication overhead.

Smart embedded objects such as sensors and actuators will become an important part of the Internet of Things. With recent technologies, it has now become possible to deploy a sensor network and interconnect it with IPv6 Internet. However, several manual configuration steps are still needed to integrate a sensor network within an existing networking environment. In this paper we describe a novel self-organization solution to facilitate the deployment of sensor networks and enable the discovery, end-to-end connectivity and service usage of these newly deployed sensor nodes. The proposed approach makes use of embedded web service technology, i.e. the IETF Constrained Application Protocol (CoAP). Automatic hierarchical discovery of CoAP servers is one of the key features, resulting in a brows able hierarchy of CoAP servers, up to the level of the sensor resources, which can be accessed both over CoAP and HTTP and through the use of either DNS names or IPv6 addresses. To demonstrate the feasibility of our approach we have implemented the solution and deployed it on a test setup, which is publicly accessible to everyone.

Today, the IETF Constrained Application Protocol (CoAP) is being standardised. CoAP takes the internet of things to the next level: it enables the implementation of RESTful web services on embedded devices, thus enabling the construction of an easily accessible web of things. However, before tiny objects can make themselves available through embedded web services, several manual configuration steps are still needed to integrate a sensor network within an existing networking environment. In this paper, we describe a novel self-organisation solution to facilitate the deployment of constrained networks and enable the discovery, end-to-end connectivity and service usage of these newly deployed sensor nodes. By using embedded web service technology, the need of other protocols on these resource constrained devices is avoided. It allows automatic hierarchical discovery of CoAP servers, resulting in a browsable hierarchy of CoAP servers, which can be accessed both over CoAP and hypertext transfer protocol.