By Claire Swedberg
Dec. 14, 2011—
KCF Technologies, a spin-off company created in 2000 by the
Pennsylvania State University, is commercializing energy-
harvesting wireless sensors, after a decade of research and development. The complete system, known as Smart Diagnostics, consists of active
RFID tags with built-in vibration and heat sensors, RFID receivers and software to manage data from sensor readings. It is designed for rugged industrial and military applications, to help users monitor the condition of machines in areas where it's inconvenient or impossible to manually take regular sensor readings.
Currently a paper plant, three power-generation companies and a university are testing a beta version of the technology. The university has attached the sensors to large HVAC units, while the other companies are monitoring the health of manufacturing or utility equipment. The
Department of Defense (DOD) is using several kits that include the KCF sensors, receivers and software for tracking the condition of helicopter blades. In addition, the company says, the DOD is testing the technology on the U.S. Navy's nuclear submarines for a
Small Business Innovation Research (SBIR) project, with tags placed on certain parts of the submarines. With all the deployments, users are monitoring the condition of their machinery based on the levels of vibration and heat and any fluctuation of those levels, with the data transmitted to their back-end systems via active RFID.
KCF Technologies offers a variety of technology solutions related to
sensor data. One of those products is the Smart Diagnostics system, which was developed with financial support from the
U.S. Department of Energy, in support of the agency's effort to improve machine-health monitoring and thus increase energy efficiency, and with the DOD. The company was founded, says David Shannon, KCF's business development and marketing VP, in part to enable "the Internet of Things for very hard problems." The company has been focusing on a system that would allow companies such as manufacturers or utility companies to track the condition of their equipment—located in remote areas or somewhere in which human access may be limited—in real time without requiring an individual to walk through their facility and take sensor readings manually.
The health and efficiency of a piece of equipment—such as a compressor, chiller, generator or fan—can be gauged by its temperature and vibration, says Shannon. When a piece of equipment begins to fail, its vibration level and temperature may rise very gradually—something that is hard to detect unless sensor readings are taken on a regular basis. While companies that manufacture the equipment sometimes offer sensor technology, the sensors typically must be wired, and that can be very expensive. KCF was looking for an easier, less costly solution for companies that may not have the budget size to purchase the wired solution and install it.
KCF developers tested existing off-the-shelf
RFID hardware and found that none provided the functionality needed in rugged environments, or were capable of transmitting
sensor data with minimal power. Therefore, KCF's team came up with active 2.4 GHz RFID sensor tags of their own, with a proprietary air-interface
protocol. "The challenge was pulling relatively high bandwidth info—temperature and vibration sensor data—in a very low power way over a radio network," Shannon says.
The resulting sensor tags can be operated by either by a AA battery (which will last about eight years, if the tags transmits data every minute), or by a choice of three forms of energy harvesters that use thermal, solar or vibration energy. A KCF tag measures about 1 inch by 1 inch by 2.45 inches, has built-in vibration and temperature sensors and can be affixed directly to a machine either with screws, a magnetic mount or epoxy. The magnetic mount is preferable, says Shannon, if the tag is going to be moved from one machine to another over time. The energy harvester plugs into the device and would be attached separately. The vibration harvester draws energy from the vibration of the machines. The temperature harvester draws power from the heat—the machine would need to be 10 to 15 degrees warmer than the ambient air. The solar harvester may be the more appropriate choice in the case of a machine that is outdoors and receives direct sunlight.
The
tag can be preset to send data at specific intervals from once a minute to once a day. It transmits its own unique ID number and sensor data to a receiver—another relatively small device measuring 1.8 inches by one inch by 2.5 inches. The
read range is typically 70 to 100 meters, depending on the environment and any obstructions. Typically about 24 sensors tags can transmit to a single receiver. The receiver is connected with a
USB cable to a laptop or PC or a "collection server box" on which KCF's Smart Diagnostics software resides. The software, which is based on Microsoft's SQL, gathers data and makes it available to the end user in the form of a list of sensor readings for each machine. It can also show alerts to users logged onto the system, if there is a change in readings over time.
By late January KCF expects to begin selling the system commercially as a kit designed to enable users to get a small-scale system set up very quickly. The kit will cost less than $5,000, Shannon says, for three to10 sensors (depending on the end user's needs), a receiver and software. After using the kit, end users could then determine whether they want a full-scale deployment.
A beta version of the kit is being tested by the university and companies, as well as by the DOD on the submarines (the DOD is also using an earlier version of the technology designed specifically for monitoring vibration in the helicopter blades). The customers are testing the kits with sensors on a limited number of machines. They are then comparing the results against the time required to obtain sensor reading manually, as well as the accuracy and quantity of data in the Smart Diagnostics application versus the manual method.
