1. Actuators and Control, Part 5 Grant Agreement No 518656-LLP-1-2011-1-UK-LEONARDO-LMP Project acronym: CLEM Project title: Cloud services for E-Learning in Mechatronics Technology

2. Analogical Control Servo control, as "motion control" or "robotics" is used in industrial processes to move a specific load in a suitable way. These systems can use Pneumatic actuation technology, Hydraulic actuation technology, Electromechanical actuation technology. The choice of the actuator is based on power, speed, precision, cost requirements. Electromechanical systems used high precision, low to medium power and high-speed applications, are flexible, efficient, and cost-effective.

3. The basic architecture of a motion control system contains: A motion controller to generate set points, the desired output or motion profile, and close a position or velocity feedback loop; A drive or amplifier to transform the control signal from the motion controller into a higher power electrical current or voltage that is presented to the actuator; An actuator such as a hydraulic pump, air cylinder, linear actuator, or electric motor for output motion; One or more feedback sensors such as optical encoders, resolvers or Hall effect devices to return the position or velocity of the actuator to the motion controller in order to close the position or velocity control loops; Mechanical components to transform the motion of the actuator into the desired motion, including: gears, shafting, ball screw, belts, linkages, and linear/rotational bearings. The interface between the motion controller and drives it controls is very critical when coordinated motion is required, as it must provide tight synchronization. Include Ethernet/IP, Profinet IRT, Ethernet Powerlink, and EtherCAT. Common control functions include: Velocity control; Position (point-to-point); Pressure or Force control; Electronic gearing or cam profiling. Analogical Control

4. Fig. 49 A scheme of components of servo-system. Analogical Control

5. Analogical control: Example n.5 A data transmission network for industrial application, which represents a simple example of a production plant has been designed and tested in Cassino. Three different types of automatic systems have been considered: a positioning system that was based on the use of a brushless motor; a pneumatic positioning servo-system; an event-based on/off pneumatic system. The Rockwell Automation NetLinx architecture of communication has been adopted. The network has been realized by using switch (RS-2 FX / FX Hirshmann); Ethernet/IP network. The transmission network consists of: three different Flex I/O devices to interface with the three different automatic systems.

6. Fig. 50 A scheme of industrial network. The experimental test-bed is composed by: a control test-bed, a network, three different automatic systems. The control test-bed consists of: one PLC CompactLogix L35E ; one AD/DA converter; one PC for programming the PLC software RSLogix 5000, one Panel View Plus interface.

7. Analogical control: Example n.5 Figure 51 shows a scheme of the proposed electric drive system for the positioning control, which is composed by a brushless motor of type Y-3023-2H Allen Bradley and its drive system, Ultra 3000. a specific Ultraware software has been used in order to manage the brushless motor. Ultraware software configures the brushless motor by defining its model, the type of the control signal, and the feedback signal. Fig. 51 Lay-out of electric drive system for the control position.

8. Fig. 52 – Example of velocity control by using the electric drive system. Figure 52 shows an example of the voltage signal that is imposed to the brushless motor V SET, and the response V F/B. One can note that, a good agreement between input and output signals. Analogical control: Example n.5

9. The scheme of electro-pneumatic test-bed for position control of an automatic system consists of : a linear double-acting pneumatic cylinder with double rod, this is mounted in a horizontal position; a pressure transducer has been used in order to provide an indication on the pressure level. The movement of the piston depends on the level of pressure in the two chambers of the actuator, which are operated by a flow-proportional valve. The position of the actuator rod is detected by a linear position transducer which is rigidly connected to the stem. The servo-system is managed by the PLC through a Flex I/O which receives the voltage signal V t from the position transducer and sends the command Vref to the solenoid valve.

10. Fig. 53 Layout of electro-pneumatic test-bed for position control. Fig. 54 A view of experimental test-bed. Analogical control: Example n.5

11. Fig. 55 A scheme for the position control. Fig. 56 – RSLogix: routine Control” The position control has been obtained by means of a specific subroutine called "control" that compares the input values Vset and Vt and generates a signal Vref. If the value of Vref is within the range + 5Vdc ± 0.1V, the solenoid valve does not allow the air flow, and therefore the actuator remains in the previous position, otherwise, it produces a displacement of the piston-rod of the cylinder.

12. Analogical control: Example n.5 The electro-pneumatic system is based on on/off technology has been built by using FESTO equipments. Fig. 57 Example of Electro-pneumatic position control system. Fig. 58 Lay-out of electro-pneumatic system with on/off technology.

13. Fig. 59 A view of experimental electro-pneumatic test-bed. Fig. 60 Displacement-set diagram. Analogical control: Example n.5

14. Fig. 61 Diagram of logical states for control signals. Figure 61 shows the trend of the logic states for control signals which is transmitted to the pneumatic digital solenoid valves. The logic state "1" indicates the activation of the corresponding command signal The logic state "0" indicates the deactivation of the corresponding command signal. The sequence of activation and deactivation control signal corresponds to the displacement-set diagram, Fig.60.

15. Analogical control: Example n.5 Fig. 62 Logic diagram or the electro-pneumatic circuit in Fig.58. The automatic cycle of Fig. 60 has been programmed as reported in Fig. 62, and implemented in a PLC controller of type Mitsubishi, in order to test the proposed on/off automatic system of Fig.59.