A Wireless Instrumentation Control System Based on Low-Cost Single Board Computer Gateways

Abstract

Nowadays, most of the automatized measurement processes are carried out by VISA (Virtual Instrument Software Architecture) compatible instruments, that execute the instructions provided by a host computer connected through wired standard buses, as USB (Universal Serial Bus), GPIB (General-Purpose Instrumentation Bus), PXI (PCI eXtensions for Instrumentation) or Ethernet. To overcome the intrinsic limitations associated to these wired systems, this work presents an instrumentation control system based on the IEEE 802.11 wireless communications standard. Intended for instruments having a USB control port, this port is connected to a gateway based on a compact Raspberry Single Board Computer (SBC) and thus the instrument can be connected to the host computer via Wireless Fidelity (WiFi), easily allowing the deployment of an ad-hoc instruments communication network in the working area or its connection to a previously deployed general purpose WiFi network. Developed under Python, the operation commands, wireless link protocol, and USB connection allow two modes of operation to provide system flexibility: a live mode, where commands are sent individually from the host computer to the selected instrument; and a standalone mode, where a full measurement process can be entirely downloaded in the gateway to be autonomously executed on the instrumentation. The system performance in both operation modes, distance of operation, time latencies, and operating lifetime in battery operation have been characterized.

Ethernet Packet to USB Data Transfer Bridge ASIC with Modbus Transmission Control Protocol Based on FPGA Development Kit

“…A digital circuit of the transformation and transmission bridge was built and verified using two PCs and an FPGA development kit. The measured results present that the measured throughput, latency, and power consumption in this study are superior to those reported in [13,[16][17][18][19] and that only the Modbus TCP protocol is used in this study. Note that the proposed Ethernet and USB interface achieves the highest throughput (950.31 Mbps) and the lowest latency (18.845 µs).…”

“…Table 2 summarizes the measured specifications of the proposed Ethernet and USB bridge developed herein with FPGA (FPGA development kit)/PL (programmable logic) and compares them with those of previous studies. The performance comparison proved that the measured throughput, latency, and power consumption in this study are superior to those reported in [13,[16][17][18][19] and that only the Modbus TCP protocol is used in this study. The TCP/IP protocol is popular in [13,19] and this study.…”

“…The performance comparison proved that the measured throughput, latency, and power consumption in this study are superior to those reported in [13,[16][17][18][19] and that only the Modbus TCP protocol is used in this study. The TCP/IP protocol is popular in [13,19] and this study. Meanwhile, the ARP protocol is used in [13,17] and this article.…”

The Evolution of Quality Education: Impacts and Challenges of Using Open Educational Resources (OER) and Open Educational Practices (OEP) in the Conceive - Design - Implement - Operate (CDIO) Framework

“…SBC are also used when standard PCs are unsuitable [10]. The low power consumption of SBC also benefits wireless sensor networks and traditional data centers with up to 23x reduction in power consumption [11].…”