Abstract:In order to solve problems that traditional contact-based sensing instruments are interference with berthing operations and maintenance difficulties while measuring berthing loads on ships,and non-contact methods of laser rangefinders and sonar sensors are affected by lighting and environmental conditions,we propose a method for load sensing during coastal berthing on the basis of digital image measurement.Relying on a wharf project at Ningbo-Zhoushan Port in Zhejiang Province,we use the method to compute the deformation displacement of rubber fenders by analyzing speckle patterns in two images taken before and after deformation.By leveraging the known specifications of the rubber fender and the deformation displacement data,we calculate the impact energy and fender reaction force,allowing for the estimation of berthing loads.The results of field tests demonstrate that compared to conventional strain gauge measurements,the error margin of this method is less than 10%,validating its effectiveness in sensing berthing loads through on-site application.