Internet of Things (IoT) sensor networks have proven to change the game of industrial automation, renewables and intelligent lighting systems by improving efficiency with real-time data and reducing downtime through predictive maintenance. However, as systems are equipped with more and more wireless sensor nodes, designers will face the challenge of reliably expanding these Industrial Internet of Things (IIoT) networks in harsh environments while minimizing implementation and operating costs, addressing network congestion and ensuring security.
This paper provides an overview of the various problems faced by designers in expanding IIoT networks. Digi's Low-Power Bluetooth (BLE) module and development kit are then introduced to illustrate how these products can quickly and effectively solve the above problems.
Challenges in Expanding Wireless IoT Infrastructure
IIoT covers a wide range of applications where data acquisition is essential to improve efficiency and predictability. Taking intelligent lighting as an example, wireless sensors collect ambient light and occupancy rate data, and adjust the use in real time to save energy consumption and related costs.
Similarly, renewable energy applications utilize a remote IOT sensor network to monitor various energy sources such as solar and wind energy. These networks monitor the state and performance of the system, predict faults and dynamically regulate the grid supply.
As with other areas where industrial automation technology is used, collecting data from moving parts is key to performing predictive maintenance. Hundreds of wireless sensors are installed throughout the industrial system, providing fine-grained data information to optimize processes, reduce maintenance, and reduce operating costs. However, as the size of the sensor network expands, there may be issues that affect performance, such as
Disturbance: Industrial environments are often affected by high levels of electromagnetic interference (EMI) generated by motors, switching mode power supplies, and arc welding equipment. This EMI causes an intermittent reduction in the data transmission rate, which can seriously affect the effective transmission of data.
Network over-crowding: Operating multiple wireless devices in close proximity can cause network saturation, resulting in greater latency and connection outages, which can impede real-time detection and increase power consumption.- g.
Security: hacker attacks are a hazard to critical infrastructure, such as energy or logistics, so sensor networks must have robust security. However, as the number of endpoints increases, the number of vulnerabilities increases.
Another challenge is to integrate wireless sensors with standard industrial protocols. This integration may involve reformatting and compressing data to reduce network traffic; However, these processes need to be performed on the device, and costs and power consumption escalate rapidly as the number of sensors and protocols increases. In addition, the increasing number of sensors in the field has led to more and more complex maintenance because of the unpredictability of sensor maintenance, whether it is a failure or just battery replacement.
Bluetooth technology in large scale IIoT
Among the many IIoT wireless protocols, Bluetooth is a powerful solution to solve a range of problems as the sensor network expands. For example, by using adaptive frequency hopping (AFH), Bluetooth technology improves immunity. The AFH divides the data into small packets and transmits it over multiple frequencies and then recombines it at the receiving end. Any lost packets are retransmitted after a loss report is sent to ensure communication reliability and prevent loss of long information due to electromagnetic interference.
To avoid over-crowding of the network, Bluetooth technology supports controlling the transmit power relative to the receiver after the connection is established. This approach, combined with AFH, contributes to energy savings while minimizing EMI, enabling hundreds of wireless devices to operate in the same space. In addition, Bluetooth technology reduces security vulnerabilities by using powerful encryption and resilient verification protocols.
In IIoT deployments, the large scale Bluetooth sensor network communicates mainly through gateways designed to mate with multiple devices. By building sensor nodes around Bluetooth, developers can realize seamless interoperability with smartphones and tablets, thereby simplifying setup and diagnostics and improving maintenance efficiency.
However, in order for wireless networks to adapt to IIoT, Bluetooth sensor networks must also reliably adapt to harsh deployment conditions, reduce power consumption, increase cost effectiveness, and simplify maintenance.
Building IIoT Networks with Industrial-GradeBLE BLE Modules
Using Digi's XBee 3 BLU BLE 5.4 module and development kit, designers can quickly and directly deploy wireless IIoT networks. The module has an industrial temperature range of - 40 ° C to+85 ° C and uses idle and dormant operating modes to meet reliability and power consumption requirements. The current consumption of the XBee 3 BLU device is 7.5 mA (mA) and 8 microamperes (µ A), respectively, which can support the long-term installation of remote sensors in difficult locations, so valuable information can be obtained without periodic battery replacement.
Other features include:
The maximum data transmission rate is 2 megabits per second (Mb/s), which provides detailed information on the operation of complex machinery
The maximum transmitting power is+8 dB milliwatts (dBm), which can realize high-fidelity communication within the direct vision range of 15 meters (m) indoor or 300 meters outdoor
Digital I/O and 4 10-bit ADC inputs for flexible integration with different device and sensor interfaces
V to 3.8 V power supply, flexible power selection
Digi TrustFence Security for device and network protection, including secure boot, protected hardware ports, and device verification
State-of-the-art Microprogrammability for fast development of data processing and decision systems on the device
Fully regulated in North America (FCC, IC) and Europe (ETSI)