What Is Motion Control?

Motion control is sub field of automation. This controls the position or the velocity of the machinery. To do this it uses device like a linear actuator, electric motor, hydraulic pump or generally a servo motor.  This is a very important part of robotics and CNC machine tools. This is a very complex system as the kinematics in these machines is usually very simple. Motion control is used greatly in packaging, textile, semi conductor, printing and assembly lines.

The basic design of the motion control is as follows. The control is set to generate set points for the desired outcome and to close positions or velocity (the feedback loop). The signal is then changed into an electrical current by a drive or an amplifier. This is then delivered to the actuator. (An actuator is for motion output and can be a hydraulic pump, electric motor or a linear actuator.)  Some newer models are more accurate because they can close the position internally. 

Feedback sensors such as Hall Effect devices or optical encoders are used to close the position of the actuator bring it back to the motion control. The mechanical components then change the motion into a required movement. This can include shifting, belts, ball screw, gears, and linkages linear or rotational bearings. When co-ordinated motion is required the interface between the motion controllers are critical. They have to provide tight synchronisation.

There are some common control features and these include position control (this is often based on the velocity profiles for example S-curve or triangular profile.), velocity, electronic gearing (also known as cam profiling) this is where the master axis and the position of the slave axis are mathematically linked. For example, when two rotating drums turn at a set ratio to one another, there is also electronic camming and this is where the slave axis abides by a profile that is the job of the master as this does not need to be salted but it has to be animated. There is also pressure and force control.

Motion controllers are used in an array of different industries to help produce and make most of the things we use every day. They help do the jobs that are hard labour for humans and assist in increasing productivity.  There are several companies that globally sell these controls. They develop, manufacture and market servo drives and systems. Their products are predominantly brushless controls; however they do provide drives for alternate motor types. They also provide standard products and can customize to suit your needs.