Description

Introduction

This coursework exercise will provide you with the opportunity to demonstrate the skills you will develop throughout the module. Specifically, the following learning outcomes will be assessed:

⦁ the knowledge to describe the properties of measurement systems and sensors and evaluate their application in selecting an appropriate approach for a given application

⦁ the knowledge to analyse signal conditioning and data capture systems using components such as operational amplifiers, analogue to digital converters and microcontrollers. 

⦁ the ability to design and implement an automated program using flow charts to solve a range of problems to include the control of common actuators.

⦁ Design and specify measurement and sensor systems to interface with microprocessor and PLC based applications (partly assessed).

These learning outcomes will be assessed through the year through as you work through a mini-project where you will complete various activities 

Scenario,

This work follows on from part A of the coursework where you have previously designed the control system for a manufacturing company’s paint booth.  For this part of the coursework, you have been contracted to develop the control system for monitoring behaviour of the heating elements and temperature sensors within the paint booth. 

The monitoring system for the paint booth will be controlled using a PIC18F2455 microcontroller. This will read the temperature within the paint booth using a Microchip MCP9701-E/TO, Voltage Temperature Sensor in this application. The datasheet can be found here: 

https://docs-emea.rs-online.com/webdocs/1381/0900766b813818ab.pdf

The required operating temperature is between 60oC and 90oC

Task 3 – Sensor Evaluation and Signal Conditioning (10%) 

As part of the tendering process, you are required to provide a brief (maximum 1 page) summary of the suitability of the proposed sensor indicating: 

⦁ Whether the sensor is suitable/optimal for this purpose. 

⦁ Whether a signal conditioning system could enhance its operation. 

⦁ Any alternative recommendations you wish to make 

You should support your conclusions with appropriate calculations to show the thresholds that will be used within the microcontroller program. You may also wish to comment on the linearity, sensitivity, range and accuracy of the proposed sensor in your analysis. 

Task 4 - Monitoring System Design (40%) 

The system should operate using the following rules

⦁ When the heating elements are activated, the microcontroller will receive a signal to indicate that the heating process has begun. 

⦁ The microcontroller should take temperature measurements every 15 seconds during the process 

⦁ An alarm signal will be generated if the “warning conditions” indicated below are met. 

⦁ A “stop” signal will be generated if the “stop conditions indicated below are met. 

The warning conditions indicate that the process is operating outside of defined bounds in order to alert an operator to intervene. These conditions are: 

⦁ The temperature moves out of the defined range for more than 2 consecutive temperature readings. 

⦁ The heating system does not shut down after five minutes. 

The stop conditions are used when the process is potential becoming unsafe and must immediately be stopped automatically. These conditions are: 

⦁ The temperature exceeds the upper defined limit by more than 10o Centigrade 

⦁ The system moves out of the defined range for more than 4 consecutive temperature readings

⦁ The heating system does not shut down after six minutes. 

The deliverables for this task are as follows: 

Microcontroller Design Notes (20 Marks)

Your company has been asked to submit a comprehensive a set of design notes for the Microcontroller program based on the required functionality described above. This is part of the tender process and will help the engineering team at the articulated truck company make the decision on which OEM to award the contract to.  This should include: 

⦁ A list of the inputs and outputs and the pin they are to be connected to on the ECIO28

⦁ Any assumptions you have had to make 

⦁ Flowchart 

⦁ Variable list

Microcontroller Program/Simulation (20 Marks)

You should build and simulate your program using Flowcode. You should upload your Flowcode file with the following: 

⦁ The temperature sensor input should be simulated by a potential divider. 

⦁ A toggle switch should be used to indicate the heater is operating 

⦁ The outputs should be indicated by appropriately labelled LEDs. 

⦁ The 3D dashboard should be used for the simulation and should be designed to a professional standard.

Marking Scheme

Task 3 – Sensor Evaluation and Signal Conditioning (10%) 

Critical evaluation of the proposed sensor and it’s suitability for use with the ECIO. 

Calculation of required thresholds for sensing application.  

/10

Task 4 - Monitoring System Design (40%) 

Microcontroller Design Notes

⦁ Any assumptions you have had to make 

⦁ Flowchart (plan)

⦁ I/O list

⦁ Variable list

/10

Microcontroller Program/Simulation 

Working simulation of required functionality: /20

Structure of program: 

⦁ Clear logical structure  

⦁ Use of sensible/appropriate variable names  

⦁ Clear and appropriate use of comments 

⦁ Minimal solution

/10

N.B. Written elements will be assessed using the University of Sunderland Generic Assessment Criteria    https://docushare.sunderland.ac.uk/docushare/dsweb/Get/Document-7861/AQH-F6-15%20Generic%20Assessment%20Criteria.pdf

Figure 1 – Input Devices  

Figure 2 – Output Devices

Table 1 – Paint Booth I/O

Signal name PLC Input/output Description

System Ready Normally open push button

Extraction on Normally open push button

Stop Normally Closed push button

Emergency Stop Normally closed latched button

Parts in Position 1 Proximity Sensor

Parts in Position 2 Proximity Sensor

Red Indicator Light System Ready Light

Conveyor 1 24v contactor

Extraction Fans 24v contactor

Extraction On Blue 24v Indicator Light

Conveyor On Green 24v Indicator Light

Oven On Green 24v Indicator Light

Oven Heating Elements 24v Contactor

Instruction Files