Interaction force between needle and biological tissue is studied. The puncture force is modeled. A force sensing detection system of biological soft tissues is built. The system consists of both hardware and software components. The needle is powered by high-precision displacement platform made in German. The piezoresistive force sensor is used for force signals detecting and the acquisition card is used to collect force signal in real-time.The LabVIEW is used to control motor movement and data acquisition. With experimental platform

the needle penetration experiment is carried out. MATLAB is used for experimental data processing and analysis

the puncture force-displacement curve is formed and the relationship between various factors and force-displacement curve is conducted.