TreeSonic

TreeSonic is designed to measure stress wave propagation time in trees in fibre direction. The signal is generated by a hammer tap on the start sensor. By measuring the distance between the two sensors, velocity in fibre direction can be calculated. Fibre direction velocity correlates well with elastic modulus and yield strength of wood. In this way wood material of the tree can be graded before cutting.

Operation

Both the start and stop sensors can be easily fixed with the integrated moving weights with one or two moves. To generate a signal, a hammer tap is required on the start transducer. This generates a stress wave in the tree and in the same time starts the built-in microsecond precision timer. When the stress wave reaches the stop transducer the timer is stopped and the measured traveltime is displayed on the screen. Removal of the sensors can also be done with by the moving weights.

Patent

TreeSonic is patented under US6871545. The patent holder is Weyerhaeuser Co., the inventor is Chin-Lin Huang and the manufacturer is Fakopp.

Package contents

• TreeSonic unit
• Two piezo transducers with cables
• Hammer
• Aluminum case

Technical parameters

Time resolution	1.2 microseconds
Weight of timer incl. battery	0.35 kg
Weight of hammer incl. handle	0.25 kg
Weight of start transducer	1.2 kg
Weight of stop transducer	1.1 kg
Total weight	2.9 kg
Dimensions	36 x 84 x 184 mm
Battery	1 x standard 9V rechargeable battery
Operation time with one recharge	around 20 hours
Power consumption	75 mW
Water resistance	partly, IP65 protection