A new apparatus for force measurement in marine bioadhesion

A new and versatile apparatus designed for measuring the tenacity of marine invertebrates that adhere either permanently or temporarily, is described. In order to test Stefan type of adhesion (law of tack) a constant rate of separation was necessary and this has been achieved by incorporating a closed-loop feedback circuit that acts on the servo-motor. The force (up to 50 kg) is measured by means of a load ring coupled to a linear variable displacement transducer and the accuracy (linearity of the output) is independent of the range of force applied. The apparatus is easy to operate, easily transportable and of relatively low cost.