tailieunhanh - Giáo trình robot - Phần 5

Tham khảo tài liệu 'giáo trình robot - phần 5', kỹ thuật - công nghệ, tự động hoá phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Part IV Advanced Topics Introduction to Part IV In this last part of the textbook we present some advanced issues on robot control. We deal with topics such as control without velocity measurements and control under model uncertainty. We recommend this part of the text for a second course on robot dynamics and control or for a course on robot control at the first year of graduate level. We assume that the student is familiar with the o nu functional cpaces ia. the spaces L-2 and Lx. If not we strongly recommend the student to read first Appendix A which presents additional mathematical baggage necessary to study these last chapters P D control with gravity compensation and P D control with desired gravity compensation Introduction to adaptive robot control PD control with adaptive gravity compensation PD control with adaptive compensation. 13 P D Control with Gravity Compensation and P D Control with Desired Gravity Compensation Robot manipulators are equipped with sensors for the measurement of joint positions and velocities q and q respectively. Physically position sensors may be from simple variable resistances such as potentiometers to very precise optical encoders. On the other hand the measurement of velocity may be pw through . hMt-cOm-i-W of the velocity frhinthe position sensed by l iplK ipo ssJiirnrah to the high precisionof the position measurementsby be optical encoders the msm ac Jkhttl by the methods may be qrnte mediocre in accsracy epecihcaltyfor certain intervals of velocity. On certain occasions this may have as a consequence an unacceptable degradation of the performance of the control system. The interest in using controllers for robots that do not explicitly require the measurement of velocity is twofold. First it is inadequate to feed back a velocity measurement which is possibly of poor quality for certain bands of R avoidingtheud oft elcxdtyineo uremmits einm the need for velocity sensors such as .