“An ounce of prevention is worth a pound of cure” is the mantra of maintenance teams in numerous industries around the world. Tasked with keeping decades-old critical systems functional beyond their planned operating lifespan while operating under constrained budgets, maintenance teams are searching for new methods to proactively identify and repair structural related issues before they become critical. Case studies in multiple industries have shown that pro-active preventative maintenance (PM) provides significant cost avoidance by reducing both planned and unplanned repair costs as well as extending components’ lifecycle. Detailed fatigue data is the foundation of such a PM program and drives scheduled repairs.

The challenge to date (beyond visual inspection) has been how to efficiently obtain detailed scientific fatigue-monitoring data during routine cycle maintenance initiatives while maintaining cost effectiveness.


While technology has made quantum leap advances over the past decades, fatigue measurement is still mostly done with an electric resistance strain gage, which has remained largely unchanged since its development in 1938.

No tool will ever completely replace visual inspection. Having access to nondestructive inspection tools that can provide science based data BEFORE cracks and underlying fatigue issues are visual would provide measurable value in the maintenance arena.

Nondestructive Inspection (NDI) is the examination of an object or material with technology that does not affect its future usefulness. NDI can be used without destroying or damaging a product or material. Because it allows inspection without interfering with a product's final use, NDI provides an excellent balance between quality control and cost-effectiveness. The term "NDI" includes many methods that can:

• 1. Detect internal or external imperfections
• 2. Determine structure, composition, or material properties
• 3. Measure geometric characteristics

In two words, NOT MUCH! Digital Imaging Correlation, X-Ray diffraction and a handful of other technologies have evolved since the electrical resistance strain gage was developed. All of these tools have applications in the laboratory though taking these tools out into the field for aging aircraft applications, bridge and infrastructure applications and other field initiatives in other sectors continues to be a costly and cumbersome task.

Comparison of NDI/NDT Technologies


With nearly three decades of research and product development work combined with recent advances in microprocessor, digital camera and computer memory technologies, DMI‘s vision of developing an accurate, field and maintainer friendly NDI/NDT tool has become a reality. DMI has a full set of products providing laboratory and field technicians Go/No-Go readings. This functionality requires no wires, no soldering, no cumbersome data acquisition equipment but rather only a lightweight, affordable wire-free hand-held unit (CWV product) and a tablet PC (for Fatigue Monitoring and Residual Stress Measurement.)

A culmination of DMI’s efforts will come in 2010 with the launch of the Digital Strain Encoder, which captures data via a self-contained, self-powered sensor unit and wirelessly transmits data back to a data storage device. This breakthrough will provide the ability to receive real-time data feeds as well as frequently measure structures were access is difficult (bridges, inside plane wings, etc.).





DMI has been resolute in understanding maintenance needs and requirements and incorporating these requirements into product design and has created a portfolio of scientifically sound, artisan friendly solutions that provide accurate data for NDI, Reliability Centered Maintenance (RCM) and Conditioned Based Maintenance (CBM) initiatives providing the user with cost avoidance by minimizing planned and unplanned maintenance.


More information on DMI's products, validation testing, testing initiatives and customers can be found by navigating from the Products menu item. Additionally, Industry specific solutions may be selected from the Industries menu. To discuss a specific challenge for your company, contact DMI and our technical sales team will be happy to discuss our solution in detail with you.