Planar interdigital sensors based looseness estimation of leather

An interdigital based sensing system to measure looseness in the sheepskin to alter the tanning process to produce better quality leather has been fabricated and developed. The sensor has the planar interdigital structure and the consecutive fingers are connected to positive and negative electrodes respectively. The proximity depth of electric field can be adjusted by varying the distance between two electrodes of opposite polarity. Electric field lines pass through the leather (skin) under test, and the reactive impedance of the sensor depends on the material dielectric properties as well as on the electrode and material geometry, is measured. From the measurement the effective permittivity of the sensor is calculated which is related to the quality of leather. It is possible to predict some information of skin quality during various stages of leather processing, which will be very useful for optimizing the process of leather manufacture to achieve the desired qualities in the finished product.