Precision Motion Control: Design And Implementa...
Precision Motion Control focuses on enabling technologies for precision engineering - issues of direct importance to be addressed in the overall system design and realization: precision instrumentation and measurement, geometrical calibration and compensation, and motion control. It is a compilation of the most important results and publications from a major project that develops a state-of-the-art, high-speed, ultra-precision robotic system.
Precision Motion Control: Design and Implementa...
Precision Motion Control nicely integrates a number of important topics in precision motion control. It also comes with a complete set of references for further information. All told, it represents a useful reference and an excellent single source of essential topics related to precision motion control.
Background: Compared with conventional minimally invasive surgery and open surgery, robotic-assisted minimally invasive surgery can overcome or eliminate drawbacks caused by operator restrictions, motion limitation by the trocar and the image system, such as fatigue, trembling, low precision, constrained degree-of-freedom, poor hand-eye coordination and restricted surgical vision. In this paper, a novel partly tendon-driven master-slave robot system is proposed to assist minimally invasive surgery and a master-slave control architecture is developed for abdominal surgical operations.
Methods: A novel master-slave surgery robot system named MicroHand A has been developed. A kinematic analysis of master and slave manipulators was conducted, based on screw theory and vector loop equation. The relationships of the tendon-driven multi-DOF surgical instrument among Cartesian space, actuator space and joint space were derived for control purposes. The control system architecture of the MicroHand A was designed with intuitive motion control and motion scaling control. Llewellyn's absolute stability criterion and the transparency of the one-DOF master-slave system are also analysed.
A Control Design reader asks: I work for an OEM, and we are developing new equipment that requires multiple motion applications on one machine. This includes master-follower rollers, tension control, unwind, wind, variable speed conveyors, a precision three-axis gantry and automatic changeover position adjustments. It covers the full range of motion control from simple ac induction motors to stepper motors and precision servo control.
Dependent on the application, pneumatic positioning and motion control could be used as an alternative. This may provide a better return on investment versus precision stepper controls with a lower price point to the market, especially in areas requiring washdown and IP-rated products. Many operations performed in automation are very well suited for pneumatics, often involving repetitive fast-moving tasks that involve linear and/or rotational motion. Pneumatics can offer 100% duty cycle without heat buildup when compared to some electrical solutions and offer condition monitoring providing IoT-ready features such as valve-level diagnostics and condition monitoring solutions.
When you work with a motor vendor, they will provide a number of viable options for your application. However, your knowledge of the exact system mechanics is far greater than that of the vendor, so you should also use a motion designer tool or other sizing software that can be adjusted to your application.
Motion control is a sub-field of automation, encompassing the systems or sub-systems involved in moving parts of machines in a controlled manner. Motion control systems are extensively used in a variety of fields for automation purposes, including precision engineering, micromanufacturing, biotechnology, and nanotechnology. The main components involved typically include a motion controller, an energy amplifier, and one or more prime movers or actuators. Motion control may be open loop or closed loop. In open loop systems, the controller sends a command through the amplifier to the prime mover or actuator, and does not know if the desired motion was actually achieved. Typical systems include stepper motor or fan control. For tighter control with more precision, a measuring device may be added to the system (usually near the end motion). When the measurement is converted to a signal that is sent back to the controller, and the controller compensates for any error, it becomes a Closed loop System.
In recent years, the needs of modularized controller for the multiaxes servo system increase significantly since traditional controller still exists many drawbacks such as limited control axes, low speed data acquisition, or heavy weight. In this paper, we present the design and implementation of both hardware and software for real-time express-based motion controller. This controller can meet the demand for high-speed motion control and high performance which conventional fieldbus controllers cannot realize. With modular design, the controller brings many benefits such as low-cost, expandable ability, multiaxes control, or small physical size. Experimental results for an industrial motion system indicate that the proposed modular controller can perform well in time critical data transmission and is feasible and applicable in various fields.
Recently, there exists an innovative trend in multiaxes control that enables the fast response, supports the large number of slave devices, configures less wiring of mechanism, and ensures the high reliability. It is hard for previous network systems to be quite adaptive, but these constraints explicitly fit in well with real-time express protocol. This standard communication is primarily introduced by Panasonic group, and up-to-now it is one of the well-known network motion system in the global market. Hereafter, the contributions of this paper are that (i) a novel design of network motion module has been developed successfully. Adopting the framework of the embedded system, it was integrated into new network communication with highly real-time performance and stable protocol. In this current trend, the control issue of multiaxes becomes more critical, especially in the large-scale system. (ii) The problems that were addressed in synchronous control, network topology, time consuming, or maintenance service have been solved this by the real-time express method. (iii) The experiments with the practical servo system are established in order to prove the validity of our approach and the ability of powerful network control. The rest of this paper is organized as follows. Section 3 introduces some definitions, technical specifications, and analysis of the real-time system. In Section 4, the detailed development of hardware platform and several notifiable remarks are carried out. Also, this section briefly describes the control software which is programmed in C++ and interacted during a cycle servo. The results of experimental module have been completed to validate our proposed approach in Section 5. Several discussions consisting of experiences, practical performance, or tested method are revealed together with the conclusions with future work in Section 6.
To verify the feasible, capable, and applicable design in our approach, an experimental test is carried out as shown in Figure 7. The host PC is Dell Latitude 5500 with powerful Intel core processor. Most of control software would execute in Windows 10 operating system as shown in Figure7(a). The software-based work is mainly programmed by Visual Studio with various C++ classes supported from Windows. The firmware which is written by C language handles the important role in data processing and exchanging. The information is traded between host and motion module through USB cable. Two LAN wires (from RX port of module to TX port of A6N servo pack and vice versa). One remarkable point is that this module offers on-the-fly adjustment parameters. Hence, as soon as plugging into port, the data flow has been established continuously. Furthermore, the integrated emulator should be utilized to track each missing command or system error as shown in Figure 7(b). Its benefit is to shorten the debugging period which is usually longer.
The communication cycle significantly impacts on overall performance of the network motion system. It should be considered carefully when designing hardware schematic. This section would analyze and discuss about influence of servo cycle and developing experiences.
The contributions in this work are (1) a compact design of module for the network motion controller, (2) both hardware schematic and software implementation using the real-time express protocol, and (3) practical validation in the closed-loop servo system. From laboratory experiment, it can be clearly seen that the proposed module can meet the control constraints in motion system, automation factory, and robotics system.
Motor control algorithms regulate speed, torque, and other performance characteristics, often for precision positioning. Evaluating control algorithms using simulation is an effective way to determine the suitability of motor controller designs and reduce the time and cost of algorithm development before committing to expensive hardware testing.
Product developers must deal with increasingly complex systems, and can no longer be experts in all of the specialized engineering fields required for building its subsystems. Motion control is one of those key specialist areas of knowledge. Yet knowing the right questions to ask before selecting a device for implementing motion control in a design is not always intuitive. We use 3D printing/digital desktop manufacturing as a real-world example of how motion control impacts an application.
But today, motion control means more than merely motor control: it also means motion planning for more than one axis, or deciding all of the discrete movements that determine how objects will move in multiple dimensions over time. For several reasons, motion control is no longer just a checklist item in a design. One is because the algorithms used for implementing it have changed, and are also becoming more complex. 041b061a72