ENGINEERING TRIPOS PART IIA

EIET LABORATORY	ENGINEERING AREA ACTIVITY

Areas 5,6,7 and 8

INVESTIGATION OF THE DESIGN OF CD PLAYERS

OBJECTIVES

• to gain an insight into the engineering of a real, complex, high technology, consumer product.
• to plan a technical investigation into a defined subsystem within a CD player or CD-ROM drive.
• to gain an understanding of how the specified subsystem works.
• to make quantitative measurements of the performance of the subsystem using standard and custom-designed test and measurement equipment.
• to appreciate the system design tradeoffs within the subsystem, and between the many subsystems within the CD player.
• to make a short oral presentation on the findings to the rest of the group, and respond to oral questions from the rest of the group.

Book your place for this activity before booking for other practicals. For guidance on what the activity involves, and how to book, see the first page of this handout.

1. Introduction

This Engineering Area Activity (EAA) is available only to third year students who have chosen one of Engineering Areas 5, 6, 7 or 8 as their core group. All students in Areas 5, 6 and 7 must complete this activity. There is an alternative EAA for Area 8 'Instrumentation and Control'.

The objectives of the activity are listed above. It is more open-ended than standard laboratory experiments, and gives you more opportunity to plan and organise the work. It illustrates some of the problems and design decisions which electronic and information engineers have to deal with in practice.

1.1 Guidance for booking

The PGA takes 16 hours, using 4 consecutive "lab days" over a 2 week period (i.e. Fri, Weds, Fri, Weds); section 2 gives full details. The activity is carried out by a group of 12 students, split into 6 pairs, with the pairs working in parallel on different tasks. At the end, each pair makes a short oral presentation to the whole group on their findings, and answers any questions from the group.

7 groups (each with 6 pairs of students) can do the activity in the Michaelmas Term. To make good presentation sessions aim to fill a 'block' of 12 students. Lent bookings are only possible if the Michaelmas sessions are completely FULL. The 6 pairs in the group cover different areas of interest, namely:

The CD-ROM as a Data Store	Feedback control loops
Demodulation and Error Control Coding	Motor and drives
Optics design and the optical head	DAC and audio electronics

For details of your specific topic, you should read the the particular description sheets.

Since slots will be booked on a 'first come first served' basis you may not be able to do the topic you would most like to. Book in for the one you like best of those that are available. Although some of the topics may be closer to your particular interests than others, all of them cover topics of relevance to all Electrical/Electronic, Control and Information engineers.

Booking is on the Web for the Inglis EIET Lab, and you should write your name into one of the 'slots' BEFORE booking yourself into any other lab experiments because of the timetabling of the EAA.

2. Timetable

The timetable for each group is as follows:

Fri 1		Mon 1	Tue 1	Wed 1	Thur 2	Fri 2		Mon 2	Tue 2	Wed 2
Intro		-	-	Lab(S)	-	Lab(S)		-	-	Prep
Study		-	-	Lab(U)	Lab(U)	Lab(U)		Lab(U)	Lab(U)	Pres

(S = supervised, U = unsupervised)

Friday 1st Session

There will be a compulsory introduction in Lecture Room 3B (for 2014) at 11:10am. The activity will be explained, and you will have a chance to ask questions. You will be given copies of further material which you may need, including data sheets and instruction manuals.

For the remainder of the day, you should study your task, investigate reference material to find out information that you need, and plan your investigations. It is up to each pair to decide on the partition of work between the two members of the pair. There will normally be another group in the Inglis EIET Lab working on it at this stage, and you are asked not to disturb them at this stage.

Wednesday 1st to Tuesday 2nd

You will have access to the laboratory and equipment from the first Wednesday until the following Tuesday. In particular on the timetabled laboratory days (Wed 1 and Fri 2) demonstrators will be available in the Inglis EIT Lab in the mornings to help. Demonstrators will probably not be available in the afternoon. It will be possible to work on other occasions by agreement with the Assistant in Charge of the Inglis EIT Lab, Mr. D Gautrey and your lab bench will not be disturbed at any time during your week.

Wednesday 2nd

3. The final presentations

This should involve a technical component, reflecting your investigations, and also your views of some of the 'system-level' design issues which have led to the design being the way it is.

Each pair of students should make a presentation, which should last about ten minutes, allowing five further minutes for questions and discussion and a short 'post-mortem' of the preceding presentation.

Guidance notes will be supplied on how best to prepare this presentation. Blank OHP slides and coloured pens will be supplied, for hand drawing. Computer based presentations are encouraged and a computer will be available for the presentation session.

The member of staff present will act as session chairman.

4. Credit

The activity is for 20 marks of 'standard credit' as explained in the 'General Instructions for Third Year Coursework'. The member of staff at the initial briefing and final presentation will award these marks for satisfactory completion of the activity, to those having shown due diligence in the lab. and presentation sessions.

Dr F. Iida, October 2014