Industrial control is divided into two main directions, one is motion control, which is usually used in the field of machinery, and the other is process control, which is usually used in the field of chemical industry. And motion control refers to a kind of servo system originated in the early days, based on the control of electric motors in order to realize the control of objects on the change of angular displacement, torque, speed and other physical quantities.
In terms of focus, motor control (in this case servo motors ) is primarily concerned with controlling one or more of the parameters of pitch, speed, and position of an individual motor to a given value. The main focus of motion control is to coordinate multiple motors, to complete the specified movement (synthetic trajectory, synthetic speed), more emphasis on trajectory planning, speed planning, kinematic conversion; for example, CNC machine tools to be coordinated inside the XYZ axis motor, to complete the interpolation action.
Motor control is often used as a link in the motion control system (usually current loop, working in torque mode), focusing more on the control of the motor, generally including position control, speed control, torque control of the three control loops, generally without the ability to plan (there are some drivers have a simple position and speed planning capabilities).
Motion control is often for the product, including mechanical, software, electrical and other modules, such as robots, drones, motion platforms, etc., is the position of the mechanical moving parts, speed and other real-time control and management, so that it is in accordance with the expected trajectory and the specified parameters of the movement of the movement of a control.
The two have part of the content is overlap: position loop / speed loop / rotation distance loop can be realized in the motor driver, can also be realized in the motion controller, so the two belong to the easy to confuse. The basic architectural components of a motion control system include: motion controllers: to generate trajectory points (desired outputs) and to close the position feedback loop. Many controllers can also close a velocity loop internally.
Motion controllers are divided into three main categories, namely PC-based, specialized controllers, and PLCs, where PC-based motion controllers are widely used in electronics, EMS, and other industries; specialized controllers represent wind power, photovoltaics, robotics, molding machinery, and so on; and PLCs are favored in the rubber, automotive, and metallurgical industries. PLCs are favored in rubber, automotive, metallurgy and other industries.
Driver or amplifier: Used to convert control signals (usually speed or torque signals) from motion controllers into higher power current or voltage signals. More advanced intelligent drives can close the position and velocity loops themselves for more precise control.
Actuators: such as hydraulic pumps, cylinders, linear actuators or motors to output motion. Feedback sensors, such as opticalencoders, resolvers or Hall effect devices, feedback the position of the actuator to the position controller to close the position control loop. Numerous mechanical components are used to convert the actuator's form of motion into the desired form of motion, including gearboxes, shafts, ball screws, toothed belts, couplings, and linear and rotary bearings.
The advent of motion control has further facilitated electromechanical control solutions, such as cams and gears, which previously required mechanical structures to implement, can now be implemented using electronic cams and gears, eliminating the return stroke, friction, and wear associated with mechanical implementations.
Mature motion control products need to provide not only path planning, look-ahead control, motion coordination, interpolation, kinematic positive and negative solutions and command outputs for drive motors, but also engineering configuration software (e.g. SIMOTION 's SCOUT), syntax interpreters (not only for their own language, but also for IEC-61131 PLC language support for IEC-61131-3), simple PLC functions, PID control algorithm implementation, HMI interactive interfaces, fault diagnosis interfaces, and advanced motion controllers are able to realize safety control.