Development of robotic system for autonomous liver screening using ultrasound scanning device

Physicians use ultrasound scans to do diagnosis by making real-time images of internal organs, because such scans are safe, inexpensive, and non-invasive. However, aging society and limited numbers of physician make it difficult for patients in remote areas to be diagnosed. Besides, physician's technical skills affect the interpretation of the scans and thus the results of the examination. Thus, development of a robotic system for remote diagnosis is required to solve the problems. For this purpose, we proposed the development of a robotic system for automatic ultrasound imaging focusing on human liver. In this paper, we present several elements developed for the robotic system. First element is an algorithm for estimating the position of liver to guide the probe to scan initial position which is the epigastric region. Second element is ultrasound probe scanning protocol design to obtain whole image of the liver. Third element is force control algorithm to maintain the contact between the probe and human body even though the patient is breathing. Fourth element is an algorithm for detecting and correcting the probe's position when improper ultrasound images occurred. These algorithms with an implementation program control the apparatus: a Mitsubishi Electric's MELFA RV-1 six axis manipulator and tested on human subjects. The results confirmed the effectiveness of the approach.