Robotic manipulators for single access surgery

This thesis explores the development of cooperative robotic manipulators for enhancing surgical precision and patient outcomes in single-access surgery and, specifically, Transanal Endoscopic Microsurgery (TEM). During these procedures, surgeons manipulate a heavy set of instruments via a mechanical clamp inserted in the patient’s body through a surgical port, resulting in imprecise movements, increased patient risks, and increased operating time. Therefore, an articulated robotic manipulator with passive joints is initially introduced, featuring built-in position and force sensors in each joint and electronic joint brakes for instant lock/release capability. The articulated manipulator concept is further improved with motorised joints, evolving into an active tool holder. The joints allow the incorporation of advanced robotic capabilities such as ultra-lightweight gravity compensation and hands-on kinematic reconfiguration, which can optimise the placement of the tool holder in the operating theatre. Due to the enhanced sensing capabilities, the application of the active robotic manipulator was further explored in conjunction with advanced image guidance approaches such as endomicroscopy. Recent advances in probe-based optical imaging such as confocal endomicroscopy is making inroads in clinical uses. However, the challenging manipulation of imaging probes hinders their practical adoption. Therefore, a combination of the fully cooperative robotic manipulator with a high-speed scanning endomicroscopy instrument is presented, simplifying the incorporation of optical biopsy techniques in routine surgical workflows. Finally, another embodiment of a cooperative robotic manipulator is presented as an input interface to control a highly-articulated robotic instrument for TEM. This master-slave interface alleviates the drawbacks of traditional master-slave devices, e.g., using clutching mechanics to compensate for the mismatch between slave and master workspaces, and the lack of intuitive manipulation feedback, e.g. joint limits, to the user. To address those drawbacks a joint-space robotic manipulator is proposed emulating the kinematic structure of the flexible robotic instrument under control.Open Acces

Intuitive Instruction of Industrial Robots : A Knowledge-Based Approach

With more advanced manufacturing technologies, small and medium sized enterprises can compete with low-wage labor by providing customized and high quality products. For small production series, robotic systems can provide a cost-effective solution. However, for robots to be able to perform on par with human workers in manufacturing industries, they must become flexible and autonomous in their task execution and swift and easy to instruct. This will enable small businesses with short production series or highly customized products to use robot coworkers without consulting expert robot programmers. The objective of this thesis is to explore programming solutions that can reduce the programming effort of sensor-controlled robot tasks. The robot motions are expressed using constraints, and multiple of simple constrained motions can be combined into a robot skill. The skill can be stored in a knowledge base together with a semantic description, which enables reuse and reasoning. The main contributions of the thesis are 1) development of ontologies for knowledge about robot devices and skills, 2) a user interface that provides simple programming of dual-arm skills for non-experts and experts, 3) a programming interface for task descriptions in unstructured natural language in a user-specified vocabulary and 4) an implementation where low-level code is generated from the high-level descriptions. The resulting system greatly reduces the number of parameters exposed to the user, is simple to use for non-experts and reduces the programming time for experts by 80%. The representation is described on a semantic level, which means that the same skill can be used on different robot platforms. The research is presented in seven papers, the first describing the knowledge representation and the second the knowledge-based architecture that enables skill sharing between robots. The third paper presents the translation from high-level instructions to low-level code for force-controlled motions. The two following papers evaluate the simplified programming prototype for non-expert and expert users. The last two present how program statements are extracted from unstructured natural language descriptions

Force Sensing and Control in Micromanipulation

Ph.DDOCTOR OF PHILOSOPH

Fourth Annual Workshop on Space Operations Applications and Research (SOAR 90)

The proceedings of the SOAR workshop are presented. The technical areas included are as follows: Automation and Robotics; Environmental Interactions; Human Factors; Intelligent Systems; and Life Sciences. NASA and Air Force programmatic overviews and panel sessions were also held in each technical area

Sensor based systems for quantification of sensorimotor function and rehabilitation of the upper limb

The thesis presents targeted sensor-based devices and methods for the training and assessment of upper extremity. These systems are all passive (non-actuated) thus intrinsically safe for (semi) independent use. An isometric assessment system is first presented, which uses a handle fixed on a force/torque sensor to investigate the force signal parameters and their relation to functional disability scales. The results from multiple sclerosis and healthy populations establish relation of isometric control and strength measures, its dependence on direction and how they are related to functional scales. The dissertation then introduces the novel platform MIMATE, Multimodal Interactive Motor Assessment and Training Environment, which is a wireless embedded platform for designing systems for training and assessing sensorimotor behaviour. MIMATE’s potential for designing clinically useful neurorehabilitation systems was demonstrated in a rehabilitation technology course. Based on MIMATE, intelligent objects (IObjects) are presented, which can measure position and force during training and assessing of manipulation tasks relevant to activities of daily living. A preliminary study with an IObject exhibits potential metrics and techniques that can be used to assess motor performance during fine manipulation tasks. The IObjects are part of the SITAR system, which is a novel sensor-based platform based on a force sensitive touchscreen and IObjects. It is used for training and assessment of sensorimotor deficits by focusing on meaningful functional tasks. Pilot assessment study with SITAR indicated a significant difference in performance of stroke and healthy populations during different sensorimotor tasks. Finally the thesis presents LOBSTER, a low cost, portable, bimanual self-trainer for exercising hand opening/closing, wrist flexion/extension or pronation/supination. The major novelty of the system relies on exploiting the movement of the unaffected limb to train the affected limb, making it safe for independent use. Study with LOBSTER will determine its usability for home based use.Open Acces