PiCUS Sonic Tomograph

Municipalities and private owners are held liable for damages caused by their trees. Most often trees are broken or thrown because ofdecay by fungal infections. To avoid risks the safety of trees has to be assessed on a regular basis. 

 

The PiCUS® Sonic Tomograph is an instrument to detect decay and cavities in standing trees non-invasively. The velocity of sound waves in wood depends on the modulus of elasticity and the density of the wood itself. The PiCUS unit tracks the speed of these waves. Most damage and disease causes fractures, cavities, or rot and reduces the wood’s elasticity and density. 

 

The PiCUS Sonic Tomograph consists of 5 to 20 sonic sensors. These sensors are spaced out evenly around the circumference of the trunk. They detect stress waves induced by manual impact and propagated through the wood. This sketch displays the basic working principle, in that sound waves cannot take a direct path through the wood (red dotted line) if there is a cavity between the transmitter and receiver.