Moving the “Stress” Diagnosis into a New Era.

If you were asked to name, the most efficiently designed, complex working structure in common everyday use, what would be your answer? The electric or hybrid car? An electric generating plant? A commercial fly-by-wire airplane? Most people would respond with one of these answers, or something similar.

But how about the human body? The container of our brain.

The bone structure and muscular system that each of us use every day is regularly called upon to absorb unusually harsh loads by lifting, jumping (from one video conference to another), or perhaps running (for the athletically inclined, or for those of us with small children at home during the “new normal”).

Our skeletal system consists of many joints, most of which have to respond continually to the demands we place on them during a normal day. The skeletal and muscular systems in our bodies transit both external and internal stresses and loads through the wonderfully intricate and well-designed human body.

Similar to their use in mechanical applications like shipbuilding, aircraft design, or automobile testing, it should not be surprising to hear that Micro-Measurements experimental stress analysis and transducer–class products play an important role in the studies, diagnosis and treatments of the human.

The field of biomechanics, the name given to the study of biological structural systems, has grown tremendously in recent years. Along with this growth, the interest in, and use of, Micro-Measurements Advanced Sensors Technology strain gauges, brittle coatings, strain gage instrumentation and photoelasticity, has dramatically accelerated.

Our stress and force analysts (Application Engineers) regularly speak with founders of start-ups, medical researchers, biomechanical engineers, and laboratory technicians about test and measurement applications. Some recent projects includes the design of artificial joints using strain gages on a composite prototype replacement joint; the use of Advanced Sensors Technology CEA and EA strain gauges to measure the forces transmitted through parts of the bone structure; and, strain gauge based transducers or hybrid sensors to measure the pressures created in the bloodstream under various conditions.

One of the most interesting applications of strain gauge technology in this field is a “Biomechanical IOT Platform” which has been designed by one of our customers. The platform incorporates Micro-Measurements strain gauges built with Advanced Sensors Technology and the System 8000 DAQ instrumentation. This platform measures all forces produced by an object in contact with the surface. One such application is the various forces created by a pitcher going through a wind-up. The platform can deliver precise, accurate and reliable data concerning the nature of these actions. This information can help an evaluator determine how to improve performance, diagnose problems, plot rehabilitation progress, develop training methods, avoid possible injury. An endless number of applications are possible in both sports and medicine.

In addition to in-situ human body applications, the foil strain gauge is the main sensing element for medical devices and equipment.

A few examples are:

The Human Body in Research:

• Impact forces, fluid pressures, movement, weight and body balance.
• Non-invasive medical imaging and diagnostic tools.
• Sight, touch.
• Cardiovascular system, heart.
• Locomotor system, Biophysical.

Weighing and Force Measurement Applications:

• Bending and axial loads in medical systems under different operating conditions, robotic surgical equipment
• Body lift systems and medical scales, patient bed weighing, pharmaceutical scales.
• Motion rehabilitation machines.
• Infusion pumps.
• Blood pressure and heart rate monitoring equipment
• Prosthetics feedback control systems.
• Mammography.
• IV bag weighing.
• Infant Incubator

With an ever-increasing demand for new ultrasound, medical imaging, and robotic surgical equipment, in addition to biotech and biomedical technologies, the medical industry is a significant growth engine for VPG’s foil technology and force sensors products and solutions such as strain gauges and foil resistors. One of the latest and fastest-growing trends in the medical industry is home-based healthcare technologies, such as patient monitoring systems that is being driven by the needs of the aging baby boomer generation and the COVID-19 pandemic.

With the increasing focus on home-based applications and remote-based treatments, we are seeing an increase in the computing power of medical devices, in addition to the miniaturization of their sensing and electronic components. These advances enable smaller, more mechanically simple, and increasingly powerful designs that at the same time highly reliable and stable. The miniaturization of these sensing elements and electronic components also allow for greater portability and accessibility – key factors in home-based applications, and instrumental to the success of worldwide medical initiatives such as telemedicine and body area networks.

In 2020, the Internet of Things (IoT) and Human Health Structuring (HHS) have created many smart medical devices and elements inside or outside the human body. How the human body became smart? The key lies in real-time data capture and analytics, using various types of strain gauges and data acquisition systems.

By detecting changes in the body environment and then convert the analog physical parameters’ signals to digital data, the role of a strain gauge in the IoT and HHS is vital.

Performance, long-term stability, precise control, and safety are critical factors for every medical application. Unfortunately, for designers of medical equipment, there are some trade-offs that must be considered when designing front-end stress analysis and force measurement circuits for these devices. Performance parameters in the front-end circuit components affect diagnostic performance, just as system configuration and objectives can affect the choice of a foil strain gauge or a foil resistor.

The endless stress analysis researches in the fields of medical and biomechanical engineering will continue to expand as this exciting field grows. It is one more area where foil strain gauges are making a major contribution to the advancement of a vitally important field of science technology.