Tham khảo tài liệu 'new approaches in automation and robotics part 4', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Networked Control Systems for Electrical Drives 83 On the other hand in order to achieve near zero following or tracking error feedforward control is often employed. A requirement for feedforward control is the availability of both the velocity Q t and acceleration g t commands synchronized with the position commands 9 t . An example of how feedforward control is used in addition to the second servocontrol topology is shown in Fig. 12. The National Instruments PCI-7354 controller can be configured for any of the above servocontrol topologies. Fig. 12. Basic feedforward and PIV control topology. In order to build a positioning application the developer has to follow the stages shown in Fig. 13 which represent the steps required to design a motion application. The learner can also perform the second to fifth stages of motion application design Bauer Fedok 2003 Fedok Bauer 2005 Saliah et al. 1999 . Fig. 13. Generic steps for designing a motion application. To introduce a student to motor control the . brush servomotor set-up will provide the opportunity to learn about this motor without ever attending a laboratory session at their 84 New Approaches in Automation and Robotics institution. Since the majority of students do not have prior technical experience this remote set-up is very economical and offers students a great tool for learning about the servomechanism and data acquisition. To ensure proper performance for servomechanism the motion control system must be tuned and tested. Then the type of move profile is planed. Motion constraints are the maximum velocity acceleration deceleration and jerk that the system can handle. Trajectory parameters are expressed as a function of motor shaft revolutions. The trajectory generator takes into account the type and the constraints of motion and generates values of instantaneous trajectory parameters in real-time. Basically the student can learn about the parameters of the . servomechanism by tuning the control loop .
