BTG Research has developed laboratory scale shock tubes in several diameters that can reliably apply shock waves with realistic blast wave profiles to small areas of a test subject or candidate armor material. By varying the geometry of the driving section, a range of peak pressures and positive pulse durations can be applied.

The prevalence of blast induced traumatic brain injury in recent conflicts has motivated laboratory scale experiments on biomedical effects of blast waves and studies of blast wave transmission properties of various materials in hopes of improving armor design to mitigate these injuries. Some currently employed shock tube designs have limitations such as significant shot to shot variations in peak pressure, positive pressure durations longer than typically encountered from real threats (antipersonnel mines, hand grenades, improvised explosive devices), and waveforms that do not accurately represent the Friedlander waveform of free-field blast waves.  Typical shock tube diameters are too large to facilitate isolating exposure to a single anatomical area (head/thorax/abdomen) to isolate injury mechanisms and study wave propagation in animal test subjects and are unwieldy for tissue and cellular level experiments. 

These figures show examples of peak pressure and positive pulse duration achievable by adjusting the driver parameters and distance from the shock tube opening for 7.9 mm (above), 26 mm (left), and 40 mm (middle) diameter shock tubes.

Papers