Industrial robot control system, you must master these aspects

What is a robot control system?

If there are only senses and muscles, people's limbs still can't move. On the one hand, there are no organs to receive and process signals from the senses, and on the other hand, there are no organs that send out nerve signals to drive muscles to contract or relax. Similarly, if the robot only has sensors and drivers, the robotic arm will not work properly. The reason is that the signal output by the sensor does not work, and the driving motor cannot get the driving voltage and current, so the robot needs a controller, which is composed of hardware and software.

The function of the robot control system is to receive the detection signal from the sensor. According to the requirements of the operation task, the motors in the mechanical arm are driven just like our human activities need to rely on our own senses. The motion control of the robot is inseparable from the sensor. Robots need sensors to detect various states. The internal sensor signal of the robot is used to reflect the actual motion state of the robot arm joint, and the external sensor signal of the robot is used to detect the change of the working environment.

So the nerves and brains of the robot can be combined to form a complete robot control system.

What are the aspects of the robot motion control system?

Actuating mechanism-servo motor or stepper motor;

Drive mechanism-servo or stepper drive;

The control mechanism ---- motion controller, do the arithmetic operation control of the path and motor linkage;

Control mode-if there is a fixed execution mode, then a program with fixed parameters is compiled for the motion controller; If there is a vision system or other sensors, according to the sensor signal, a program with no fixed parameters is compiled for the motion controller.

Basic Functions of Robot Control System

1. Control the movement position of the end effector of the robot arm (that is, control the point and movement path of the end effector);

2. Control the motion posture of the robot arm (that is, control the relative position of two adjacent active components);

3. Control the movement speed (I. e. control the law of the movement position of the end effector over time);

4. Control motion acceleration (I. e. control the speed change of the end effector during motion);

5. Control the output torque of each power joint in the mechanical arm: (I. e. control the force applied to the operating object);

6. With easy to operate human-computer interaction function, the robot through memory and reproduction to complete the specified tasks;

7. Make the robot have the function of detecting and feeling the external environment. Industrial robots are equipped with visual, force, tactile and other sensors to measure, identify, and judge changes in operating conditions.

industrial robot control system

1. Industrial robot control system hardware structure

The controller is the core of the robot system. In recent years, with the development of microelectronics technology, the performance of microprocessors is getting higher and higher, and the price is getting cheaper and cheaper. At present, 32-bit microprocessors with a price of 1-2 US dollars have appeared on the market. The cost-effective microprocessor brings new development opportunities for robot controllers, making it possible to develop low-cost, high-performance robot controllers. In order to ensure that the system has sufficient computing and storage capacity, the current robot controller is composed of ARM series, DSP series, POWERPC series, Intel series and other chips with strong computing power.

In addition, since the existing general-purpose chips cannot fully meet the requirements of some robot systems in terms of function and performance in terms of price, performance, integration and interface, this has led to the demand for SoC(Systemon Chip) technology in robot systems. Integrating specific processors with the required interfaces can simplify the design of system peripheral circuits, reduce system size, and reduce costs. For example, Actel integrates NEOS or ARM7 processor cores on its FPGA products to form a complete SoC system. In terms of robot motion controller, its research is mainly concentrated in the United States and Japan, and there are mature products, such as DELTATAU Corporation of the United States, Japan Peng Li Co., Ltd. and so on. Its motion controller takes DSP technology as the core and adopts PC-based open structure.

2, Industrial robot control system architecture

In terms of controller architecture, its research focuses on the specification of function division and information exchange between functions. In the research of open controller architecture, there are two basic structures. One is based on hardware hierarchy, which is relatively simple. In Japan, the architecture is based on hardware. For example, Mitsubishi Heavy Industries Co., Ltd. divides the structure of its PA210 portable universal intelligent arm robot into five-layer structure. The other is based on function division, which considers both software and hardware, it is the direction of research and development of robot controller architecture.

3, Control software development environment

In terms of robot software development environment, general industrial robot companies have their own independent development environment and independent robot programming language.

Many universities in the robot development environment (Robot Development Environment) has a lot of research work, provides a lot of open source code, can be integrated and controlled in part of the robot hardware structure, has been in the laboratory environment for many related experiments. The existing robot system development environments at home and abroad are Team Bots,v.2.0e, ARIA,V.2.4.1, Player/Stage,v.1.6.5.1.6.2, Pyro.v.4.6.0, CARMEN.v.1.1.1, Mission Lab.v.6.0, ADE.V.1.0beta, Miro.v.CVS-March17.2006, MARIE.V.0.4.0, Flow. Designer. V.0.9.0, 2.6 Robot.

From the perspective of the development of the robot industry, there are two needs for the robot software development environment. On the one hand, it comes from the end users of robots. They not only use robots, but also hope to give robots more functions through programming. This programming is often realized by visual programming languages, such as the graphical programming environment of Lego Mind Storms NXT and the visual programming environment provided by Microsoft Robotics Studio.

4, Robot-specific operating system

(1)VxWorks,VxWorks operating system is an embedded real-time operating system (RTOS) designed and developed by Wind River in 1983, which is a key component of the Tornado embedded development environment. The VxWorks has a scalable micro-kernel structure; efficient task management; flexible inter-task communication; microsecond-level interrupt processing; support for POSIX1003.1b real-time extension standards; support for a variety of physical media and standard, complete TCP/IP network protocols.

(2)Windows CE,Windows CE and Windows series have good compatibility, is undoubtedly a major advantage of WindowsCE promotion. WindowsCE provides a feature-rich operating system platform for building dynamic applications and services for handheld devices and wireless devices, which can run on a variety of processor architectures and is typically suitable for devices that have a limited memory footprint.

(3) Embedded Linux, because of its open source code, people can modify it to meet their own applications. Most of them are GPL compliant, open source and free. Can be applied to the user's own system with minor modifications. There is a large group of developers, no need for specialized talent, as long as you understand Unix/Linux and C language. The number of supported hardware is large. There is no essential difference between embedded Linux and ordinary Linux, and almost all hardware embedded Linux used on PC supports it. And all kinds of hardware driver source code can be obtained, for the user to write their own proprietary hardware drivers bring great convenience.

(4)μC/OS-Ⅱ,μC/OS-Ⅱ is a famous open source real-time kernel, which is specially designed for embedded applications and can be used in 8-bit, 16-bit and 32-bit single-chip computers or digital signal processors (DSP). Its main features are open source code, good portability, can be solidified, can be cut, the dominant kernel, can be deterministic.

(5)DSP/BIOS,DSP/BIOS is a real-time multitasking operating system kernel designed and developed by TI for its TMS320C6000TM,TMS320C5000TM and TMS320C28xTM series DSP platforms. It is one of the components of TI's CodeComposerStudioTM development tools. DSP/BIOS is mainly composed of three parts: multi-threaded real-time kernel; real-time analysis tools; chip support library. Using real-time operating system development program, you can easily and quickly develop complex DSP programs.

5. Robot servo communication bus technology

At present, there is no servo communication bus dedicated to the robot system in the world. In the actual application process, some commonly used buses, such as Ethernet, CAN, 1394, SERCOS, USB, RS-485, etc., are usually used in the robot system according to the system requirements. Most of the current communication control buses can be summarized into two categories, namely, serial bus technology based on RS-485 and line drive technology and high-speed serial bus technology based on real-time industrial Ethernet.

intelligent robot control system

1. Open modular control system architecture: using distributed CPU computer structure, divided into robot controller (RC), motion controller (MC), photoelectric isolation I/O control board, sensor processing board and programming teaching box. The robot controller (RC) and the programming pendant communicate via serial/CAN bus. The main computer of the robot controller (RC) completes the robot's motion planning, interpolation and position servo, as well as the main control logic, digital I/O, sensor processing and other functions, while the programming teaching box completes the display of information and the input of keys.

2. Modular hierarchical controller software system: The software system is based on the open source real-time multitasking operating system Linux, and adopts hierarchical and modular structure design to realize the openness of the software system. The whole controller software system is divided into three layers: hardware driver layer, core layer and application layer. The three levels face different functional requirements, corresponding to different levels of development, each level of the system is composed of a number of functional relative opposition modules, these functional modules cooperate with each other to achieve the functions provided by the level.

3. Robot fault diagnosis and safety maintenance technology: through a variety of information, the robot fault

Diagnosis and maintenance is the key technology to ensure the safety of the robot.

4. Networked robot controller technology: At present, the application engineering of robots is developing from a single robot workstation to a robot production line, and the networking technology of robot controllers is becoming more and more important. The controller has the networking functions of serial port, field bus and Ethernet. It can be used for the communication between the robot controller and the robot controller with the upper computer, which is convenient for monitoring, diagnosis and management of the robot production line.