Asset tracking is the perfect fit for integration of global positioning and wide area data communications technologies. Early fleet management and automotive tracking applications, the pioneering users of wide area networking technologies, leveraged circuit-switched data and text messaging along with the evolving wireless Internet Protocol (IP) infrastructures as communications platforms for their applications. Today, the latest generation architectures—including GSM and GPRS—drive mobile communications and have become commonly used worldwide. Improved communications coupled with smaller and less expensive GPS chipsets combine to enable today's asset tracking applications for fleets of all sizes. These developments have given rise to the emerging asset management market where, in essence, billions of potentially connected assets—vehicles, trains, cargo containers, or machines—exist.
While numerous solutions have come to market, providing an array of connectivity alternatives for users, issues still prevent broad-based adoption. For example, the assets to be tracked tend to be nomadic in nature; they are mobile without being in constant motion and thus do not need regular communication. Because they tend to move periodically, location awareness is more event- or movement-driven and depends less on real-time data. As long as an asset is where it needs to be, when it is supposed to be there, communication can be kept to a minimum. The assets also tend to be remote, can be stored for extended periods of time, or are used infrequently, therefore requiring reduced user interaction. Drivers of the demand for low-power asset tags and their connectivity include: asset maintenance and repair, security monitoring, and requirements for location-based asset tracking for accounting and operational provisioning. With billions of unmanaged business assets, there is a growing demand for more cost-effective connectivity. Until recently, three factors have limited the market feasibility of these systems: cost of the asset tag, IT connectivity, and maintenance burden. It is difficult for companies to justify broad-scale deployment of wireless asset management when the tracking devices cost almost as much as, if not more than, the assets they are attached to; proprietary systems make it difficult to communicate with tracking devices from existing back-end applications; and maintenance requires physical contact with every device.
Overcoming Historic Barriers
In practical terms, asset management devices or tags must be capable of long battery life (on the order of months or years) and be rugged enough to survive the extreme environments in which they are often deployed. They must be easily integrated into a corporate IT infrastructure and this tends to use IP-based data transfer. Due to the "pay-per-bit" nature of cellular networks, transfer protocols must be optimized around packet size to ensure effective cost-based performance.
The longstanding barriers to RTLS-type asset management have been size, performance, and upfront and recurring costs. Until now, asset management devices have had to compromise on at least one of those parameters, if not all three. Tags contain three fundamental building blocks: an application processor, a GPS module, and a GSM/GPRS processor. Because both the GPS and GSM modules are the major power consumers, both must be used as little as possible to conserve power resources. Low-power microcontrollers are the preferred applications processor for energy consumption reasons; however, they have limited processing and memory capability, which can severely reduce the potential for optimizing data transfer. Location-based services such as geofencing (in which a virtual perimeter is defined) and bread crumb trails (in which a GPS-carrying device records its position at set times) can also be constrained by lack of MIPS and memory capacity. More powerful application processors are available but they decrease power efficiency while driving up the total system cost. Compounding the problem are the costs of changing an application to adapt to a dynamic wireless network environment. Devices that are to be deployed for years in remote out-of-reach locations must be flexible enough to allow changes to their operating parameters as well as the application itself.
In the marketplace, early entrants have been stymied by the lack of access to market of leading GSM and GPS chipsets, along with their embedded software stacks. This limits competitive architectures from the point of design and integration, through deployment and operation. An example might include the ability to access a tag in a remote facility, updating a particular parameter in software designed for a new business process. Remotely accessing the tag is critical for application efficiency and business operation. The ability to make changes to a wireless data connection in today's fluid communications network environment can be a daunting task.
Available GPS modules have targeted the navigation markets but do not directly address the challenges of low-power location with periodic tracking. Further aggravating the problem is the lack of back-end solutions. Many great ideas failed to reach the market because they couldn't overcome the challenges of scaling, remote provisioning, and device/application management.
Innovation for Next-Generation Systems
Next-generation wireless asset management systems, based on low-power hardware and service gateway middleware and provisioning, are overcoming these barriers and providing cost-effective alternatives that address the energy use, regulatory, and time-to-market issues. An example of this type of technology is the Enabler Low Power Platform (Enabler LPP) offered by Enfora. At first glance, the Enabler LPP block diagram (Figure 1) has all the same features as typical designs: GPS, GSM/GPRS, and microcontroller. However the Enabler LPP is built with energy efficiency in mind around three devices from Texas Instruments: the Locosto GSM/GPRS processor, an MSP430 microcontroller, and a NaviLinkTM 5.0 GPS receiver. When tightly coupled with software, the Enabler LPP delivers an advanced, fully integrated low-power communications platform.
Figure 1. The Enabler LPP block diagram
A core component to the evolution of these next-generation wireless asset management solutions is how they handle the distribution and optimization of device responsibilities within the platform. With the Enabler LPP, the MSP430 handles most of the power management, application, and I/O requirements. The GPS chip handles location-based services and also is responsible for processing geofence calculations needed for advanced asset tracking services. If a geofence violation is detected, the Locosto processor takes over the tracking responsibility while establishing, monitoring, and maintaining the IP connection. The Locosto processor also stores all connection parameters and hosts the TCP and UDP stack. Transfer efficiency is achieved within the same processor by optimizing the transport protocol, based on UDP and TCP, as well as GSM/GPRS network monitoring and data connection management. For designs that use rechargeable batteries, the GSM block also performs that task, reducing size, cost, and complexity without adding an additional battery charger IC.
It is also important to ensure system flexibility and adaptability to create maximum efficiency. A current meter can give an indication of the device's battery life; the Enabler LPP, for example, keeps track of how much time was spent in the different operating states and provides an accurate report of how much current has been used and for what purpose. Based on that information, the application—typically either a Web-enabled interface or an enterprise-developed application—can choose to alter the operating parameters. For instance, if it turns out that the device is getting frequent indications of movement but the GPS readings do not indicate and confirm movement, sensitivity settings can be altered remotely and a new battery-life projection will be calculated.
Graphical user interfaces help designers to create use-case studies that will predict how long a device will last in the field. These studies allow the designer to quickly see the effects on battery life if they change reporting intervals, GPS tracking times, and sleep intervals.
With the Enabler LPP, once a model is built, the application will automatically generate the script file needed to configure the device and when it is used in conjunction with the Enfora Service Gateway and Provisioner, the settings can be pushed to one or all devices in the field, simplifying maintenance, network tuning, and application performance. The Gateway will store and forward configuration data to the devices and handle all protocol conversions. It will also accept device data and make that data available to standard database applications.
Asset management will play an ever increasing role in corporate capital management and asset utilization. Asset management devices, wirelessly connected, will play a key role in reducing operating expenses and improving business productivity. Through the Internet, this next-generation technology, enables powerful new levels of asset management and permits companies to connect a broader array of devices to their IT and accounting infrastructures.