What is a robot control system?

Date:2020-04-21
With only the senses and muscles, a person's limbs still cannot move. This is partly because the signals from the senses have no organ to receive and process them, and partly because no organ sends the nerve signals that drive the muscles to contract or relax. Similarly, if the robot has only sensors and actuators, the robotic arm will not work properly. The reason is that the signal output from the sensor does not work, and the driving motor cannot get the driving voltage and current, so the robot needs to have a controller, a control system 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, each motor in the robot arm is driven, just like the activity of our human needs to rely on our own senses. The motion control of the robot cannot be separated 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 working environment.
Therefore, the combination of the robot's nerves and brain can form a complete robot control system.
What are the aspects of a robot's motion control system?
Actuator - servo motor or stepping motor;
Drive mechanism -- servo or step drive;
Control mechanism -- motion controller, do path and motor linkage algorithm operation control;
Control mode - if there is a fixed mode of execution, it is good to program the fixed parameters to the motion controller;
If a visual system or other sensor is added, the motion controller is programmed with no fixed parameters according to the sensor signal.
Basic functions of robot control system
1. Control the moving position of the end-effector of the manipulator (i.e. control the points and moving paths of the end-effector);
2. Control the motion posture of the manipulator (i.e. control the relative position of the two adjacent moving members);
3. Control the motion speed (that is, the law that controls the motion position of the end-effector changing with time);
4. Control the motion acceleration (that is, control the speed change of the end-effector during the motion);
5. Control the output torque of each dynamic joint in the manipulator :(that is, control the force exerted on the operating object);
6. With the human-computer interaction function with convenient operation, the robot can complete the specified tasks through memory and reproduction;
7. Enable the robot to detect and feel the external environment. Industrial robots are equipped with sensors such as vision, force sense and touch to measure and identify and judge changes in operating conditions.
Industrial robot control system
1. Hardware structure of industrial robot control system
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 lower and lower. High cost performance microprocessor brings new development opportunity for robot controller, which makes it possible to develop low cost and high performance robot controller. In order to ensure that the system has sufficient computing and storage capacity, currently robot controllers are mostly composed of chips with strong computing capacity, such as ARM series, DSP series, POWERPC series, and Intel series.
In addition, because of the existing general chips on the functionality and performance cannot completely satisfy certain robot system in terms of price, performance, integration and interface requirements, this creates a robotic system for SoC (Systemon Chip) technology needs and specific processors with the required interface integration, can simplify the design of peripheral circuit to reduce the system size, and lower costs.
For example, Actel incorporated the processor cores of NEOS or ARM7 into its FPGA products to form a complete SoC system. In terms of robot motion controller, its research is mainly focused on the United States and Japan, and there are mature products, such as the United States DELTATAU company, Japan friends co., LTD. The motion controller is based on DSP and open architecture.