Bulanık Parametre Ayarlamalı Görüntü Destekli Kuvvet Kontrolü

Görüntü ve kuvvet sensörleri, robot kontrolünde kullanılabilecek zengin içerikli veriler sunmaktadırlar. Bu verilerin birlestirilerek kullanılması robotların bir çok karmasık görevde basarımlarını arttırabilir. Bu bildiri öncelikle özel bir robot konum ve kuvvet kontrol problemini tanımlamaktadir. Bu problem sabit büyüklükteki bir referans kuvvetinin, dönmeye serbest bırakılmıs bir is parçası üzerine dik yönde uygulanmasını içerir. Bu problemin çözümünde, ilk olarak görüntü tabanlı hibrit konum/kuvvet kontrol yöntemi denenmistir. Bu yöntemde sabit kazanç parametrelerinin kullanımasından kaynaklanan güçlüklere dikkat çekilmis ve parametrelerinin ayarlanmasında bulanık mantık kullanılan hibrit yapıda bir kontrol sistemi önerilmistir. Sabit parametreli ve bulanık mantık parametre ayarlamalı kontrol yöntemleri doğrudan tahrikli SCARA tipindeki bir robot üzerinde denenmis ve sonuçlar karsılastırılmıstır

Bipedal humanoid robot control by fuzzy adjustment of the reference walking plane

The two-legged humanoid structure has advantages for an assistive robot in the human living and working environment. A bipedal humanoid robot can avoid typical obstacles at homes and offices, reach consoles and appliances designed for human use and can be carried in human transport vehicles. Also, it is speculated that the absorption of robots in the human shape into the human society can be easier than that of other artificial forms. However, the control of bipedal walk is a challenge. Walking performance on solely even floor is not satisfactory. The complications of obtaining a balanced walk are dramatically more pronounced on uneven surfaces like inclined planes, which are quite commonly encountered in human surroundings. The difficulties lie in a variety of tasks ranging from sensor and data fusion to the design of adaptation systems which respond to changing surface conditions. This thesis presents a study on bipedal walk on inclined planes with changing slopes. A Zero Moment Point (ZMP) based gait synthesis technique is employed. The pitch angle reference for the foot sole plane −as expressed in a coordinate frame attached at the robot body − is adjusted online by a fuzzy logic system to adapt to different walking surface slopes. Average ankle pitch torques and the average value of the body pitch angle, computed over a history of a predetermined number of sampling instants, are used as the inputs to this system. The proposed control method is tested via walking experiments with the 29 degreesof- freedom (DOF) human-sized full-body humanoid robot SURALP (Sabanci University Robotics Research Laboratory Platform). Experiments are performed on even floor and inclined planes with different slopes. The results indicate that the approach presented is successful in enabling the robot to stably enter, ascend and leave inclined planes with 15 percent (8.5 degrees) grade. The thesis starts with a terminology section on bipedal walking and introduces a number of successful humanoid robot projects. A survey of control techniques for the walk on uneven surfaces is presented. The design and construction of the experimental robotic platform SURALP is discussed with the mechanical, electronic, walking reference generation and control aspects. The fuzzy reference adjustment system proposed for the walk on inclined planes is detailed and experimental results are presented

Design of a robotic transcranial magnetic stimulation system

Transcranial Magnetic Stimulation (TMS) is an excellent and non-invasive technique for studying the human brain. Accurate placement of the magnetic coil is required by this technique in order to induce a specific cortical activity. Currently, the coil is manually held in most of stimulation procedures, which does not achieve the precise clinical evaluation of the procedure. This thesis proposes a robotic TMS system to resolve these problems as a robot has excellent locating and holding capabilities. The proposed system can track in real-time the subject’s head position and simultaneously maintain a constant contact force between the coil and the subject’s head so that it does not need to be restrained and thus ensure the accuracy of the stimulation result. Requirements for the robotic TMS system are proposed initially base on analysis of a serial of TMS experiments on real subjects. Both hardware and software design are addressed according to these requirements in this thesis. An optical tracking system is used in the system for guiding and tracking the motion of the robot and inadvertent small movements of the subject’s head. Two methods of coordinate system registration are developed base on DH and Tsai-lenz’s method, and it is found that DH method has an improved accuracy (RMS error is 0.55mm). In addition, the contact force is controlled using a Force/Torque sensor; and a combined position and force tracking controller is applied in the system. This combined controller incorporates the position tracking and conventional gain scheduling force control algorithms to monitor both position and force in real-time. These algorithms are verified through a series of experiments. And it is found that the maximum position and force error are 3mm and 5N respectively when the subject moves at a speed of 20mm/s. Although the performance still needs to be improved to achieve a better system, the robotic system has shown the significant advantage compared with the manual TMS system. Keywords—Transcranial Magnetic Stimulation, Robot arm, Medical system, Calibration, TrackingEThOS - Electronic Theses Online ServiceGBUnited Kingdo

Design of a robotic transcranial magnetic stimulation system

Transcranial Magnetic Stimulation (TMS) is an excellent and non-invasive technique for studying the human brain. Accurate placement of the magnetic coil is required by this technique in order to induce a specific cortical activity. Currently, the coil is manually held in most of stimulation procedures, which does not achieve the precise clinical evaluation of the procedure. This thesis proposes a robotic TMS system to resolve these problems as a robot has excellent locating and holding capabilities. The proposed system can track in real-time the subject’s head position and simultaneously maintain a constant contact force between the coil and the subject’s head so that it does not need to be restrained and thus ensure the accuracy of the stimulation result. Requirements for the robotic TMS system are proposed initially base on analysis of a serial of TMS experiments on real subjects. Both hardware and software design are addressed according to these requirements in this thesis. An optical tracking system is used in the system for guiding and tracking the motion of the robot and inadvertent small movements of the subject’s head. Two methods of coordinate system registration are developed base on DH and Tsai-lenz’s method, and it is found that DH method has an improved accuracy (RMS error is 0.55mm). In addition, the contact force is controlled using a Force/Torque sensor; and a combined position and force tracking controller is applied in the system. This combined controller incorporates the position tracking and conventional gain scheduling force control algorithms to monitor both position and force in real-time. These algorithms are verified through a series of experiments. And it is found that the maximum position and force error are 3mm and 5N respectively when the subject moves at a speed of 20mm/s. Although the performance still needs to be improved to achieve a better system, the robotic system has shown the significant advantage compared with the manual TMS system. Keywords—Transcranial Magnetic Stimulation, Robot arm, Medical system, Calibration, TrackingEThOS - Electronic Theses Online ServiceGBUnited Kingdo