tailieunhanh - Field and Service Robotics - Corke P. and Sukkarieh S.(Eds) P5

Các chuyên ngành cơ bản của cơ khí bao gồm: động học, tĩnh học, sức bền vật liệu, truyền nhiệt, động lực dòng chảy, cơ học vật rắn, điều khiển học, khí động học, thủy lực, chuyển động học và các ứng dụng nhiệt động lực học. Các kỹ sư cơ khí cũng đòi hỏi phải có kiến thức và năng lực áp dụng những khái niệm trong môi trường kỹ thuật điện và hóa học. Với một mức độ nhỏ, cơ khí còn trở thành kỹ thuật phân tử - một mục tiêu viễn cảnh của nó là tạo. | 136 L. Preucil and R. Mazl significantly within the last decade it can still fail from its principle and due to inaccessibility of the RF signal from satellites in particular situations. These situations are considered for critical and should be avoided from safety reasons. The GPS signal is not available in many locations due to signal shielding . in urban areas underground spaces inside buildings tunnels deep and narrow valleys etc. While the GPS is not able to meet the basic requirements in terms of integrity and availability in a general sense therefore the localization control system can t rely exclusively on the GPS. The vehicle can be equipped not only with a satellite receiver of navigation data but also it can employ other on-board sensors . odometry or inertial navigation sensor. Each of these sensors have their own specific features and disadvantages and compared to the GPS they mainly employ the dead-reckoning principle to obtain some suitable navigation information. Application of sensors for inertial navigation gyros accelerometers tilt sensors does not depend on operational condition. Their usage has to take into account many fluctuating parameters . sensor drift bias non-linearity . Precise estimation of the sensor parameters has direct impacts on desirable accuracy and reliability of the localization system in this case. Dead reckoning by the means of odometry fails if insufficient adhesion between the vehicle wheel and ground occurs due to adhesion or type of the surface . rain ice or leaves soft-type of surface . Quality of adhesion impairs particularly when the vehicle accelerates or brakes. Authors in 1 evaluate the vehicle speed based on a fuzzy inference system and neural networks using differences and rapid changes between odometry sensors joined with multiple wheels. There are many references in robotics field on data fusion from gyroscopes accelerometers and odometry. The most of them solve data fusion problems employing the .