Development of a Robot Arm Link System Embedded with a Three-Axis Sensor with a Simple Structure Capable of Excellent External Collision Detection.

In order to effectively detect the contact state between the operator and the collaborative robot, a sensor with excellent external force detection performance is needed. The existing force/torque sensor and joint torque sensor, which are the two main external force sensors methods in cooperative robots, have limitations; only the force exerted at the end effector is detected, and it induces a low stiffness in the overall structure which affects the control performance. In the case of sensorless collision detection methods that utilize the current sensor that is used for motor control, the estimation of the performance of external force is sensitive to the sensor noise and dynamic model accuracy only to the extent that it can be used for collision detection. In this paper, we propose a strain gauge-based three-axis sensor of a cylindrical shape, which is often used as a link in a robot. By integrating sensors with robot links, the external force can be precisely measured without compromising the stiffness and is decoupled with joint disturbances, such as motor friction. Sensor calibration is conducted using static load evaluation equipment, and the reliability of collision detection is confirmed by comparing the theoretical/structural analysis results. Through the weight test and sensor characteristic evaluation, the performance and output stability are validated.

A case of primary pulmonary NK/T cell lymphoma presenting as pneumonia.

Primary pulmonary lymphoma, particularly non-B cell lymphomas involving lung parenchyma, is very rare. A 46-year-old male was admitted to the hospital with fever and cough. Chest X-ray showed left lower lobe consolidation, which was considered pneumonia. However, because the patient showed no response to empirical antibiotic therapy, bronchoscopic biopsy was performed for proper diagnosis. The biopsied specimen showed infiltrated atypical lymphocytes with angiocentric appearance. On immunohistochemical staining, these atypical cells were positive for CD3, CD30, CD56, MUM-1, and granzyme B, and labeled for Epstein-Barr virus encoded RNA in situ hybridization. These findings were consistent with NK/T cell lymphoma. We report on a case of primary pulmonary NK/T cell lymphoma presenting as pneumonic symptoms and review the literature on the subject.