Kenji Ogawa Kouhei Ohnishi Evaluation of stiffness calculation for organ palpation device with electro-hydraulic transmission system based remote actuator. 378-383 2015 INDIN https://doi.org/10.1109/INDIN.2015.7281764 conf/indin/2015 db/conf/indin/indin2015.html#OgawaO15