5ET009

Department of Engineering

ASSESSMENT BRIEF

Module Title: Electro Mechanical Control Systems

Module Code: 5ET009

Component Number: 2 of 2

Weighting: 15%

Electromechanical control / pneumatic circuit design

Marking Criteria:

Learning Outcome 1 US – Underpinning Science and Mathematics US1: To assess a range of possible power sources for

open-loop and closed-loop control, drawn from electrical and mechanical engineering disciplines, including electric drives, pneumatics, electro-pneumatics, hydraulics

Learning Outcome 2 E – Engineering Analysis E3: To be competent in the use of a commercial software

packages to design, analyse and model electro- mechanical systems and fluid power systems, and to design programs for microcontroller implementation

E4: To use the top-down systems approach to design control systems

Learning Outcome 3 P – Engineering Practice P4: To be able to source information from data sheets,

journals, and internet web-sites to design and implement control systems

See weightings of each requirement

The minimum pass mark for this element is D You will pass the module if you achieve a minimum grade of D for this assignment and an average grade of D for the whole component.

Assignment handed out:

Latest date for submission: 15 July 2014 Assignments submitted after the deadline and without an authorised extension of time will be marked F0.

Please mark your assignment for the attention of: Jon. Rackley You should make it very clear what sources of information have been used; where material/information from these sources is quoted it must be clearly referenced using the Harvard Referencing System. (Details can be obtained from Learning Centres).

The assignment must be handed in to Telford Engineering Student Office, SC Block. You are advised to keep your own electronic & ‘hard’ copy of any work submitted.

5ET009 Assignment Latest Hand In Date – 15 July 2 014

A simple printing machine needs to be developed to be used to ‘Tampo’ print the name of the product on a cosmetic cream jar lid. The machine has three pneumatic linear actuators (pneumatic cylinders) Numbers 1 to 3 below.

1. Linear actuator working as positioning clamp at print station 2. Linear actuator positioning the print head left and right, to be over

the part or inking station 3. Linear actuator moving print head up and down to either pick up ink

or apply print design to the lid. The process is defined as follows An operator places the lid in the machine and closes a safety guard. Once guard is closed the operator can press the start button. On start button being pressed Actuator 1 clamps the part Actuator 3 moves down to pick up ink and up again Actuator 2 moves to position head above the print station Actuator 3 moves down to print the lid and returns up. Actuator 2 moves to position the head above the inking station Actuator 1 unclamps the part. The operator opens the safety guard and removes the printed part.

3 Print Head

Up/Down Actuator 2 Print Head

Left/Right Actuator

1 Positioning Clamp Actuator Ink Station

Lid

Speeds of all actuators needs to be controlled in both directions. Pressure control is required for the actuator 2 downward movement at print station. The time the print head is down on the lid should be set to 3 seconds but adjustable through the control programme. Using a top down approach

• Analyse with the use of a system diagram the process, defining each movement of the process, its position in the total sequence. Use rectangular boxes for operations and diamond shape for decisions. 20

• Define all the inputs and outputs required for this control system include them on the system diagram, describe them and number them so that they can be used in the PLC control system you will develop. 10

• Develop a suitable PLC circuit to control the above with where all

end conditions are fed back . 30

• Devise a pneumatic circuit to complete the above operation. 30 (Fluidsim may be used for this).

• Advise how speed control on all linear actuators would be 10 Achieved in a separate section explain where it is in you pneumatic diagram.