Module information on this degree can be found below, separated by year of study.

The module information below applies for the current academic year. The academic year runs from August to July; the 'current year' switches over at the end of July.

Students select optional courses subject to rules specified in the Mechanical Engineering Student Handbook,  for example at most three Design and Business courses. Please note that numbers are limited on some optional courses and selection criteria will apply.

Mechanical Transmissions Technology

Module aims

The course aims to cover the fundamentals of drive system and geared transmission design and technology. It is intended to develop students’ skills in various engineering science disciplines, into a capability to design and analyse transmission systems.

This Masters level, Advanced Application course builds on the knowledge gained in compulsory Engineering Science courses in earlier parts of the undergraduate curriculum, such as Stress Analysis and Materials together with a smaller amount of Heat Transfer and Fluid Mechanics. Satisfactory completion of the third year Tribology course is recommended but not compulsory.

 Lectures are aimed at providing a basic understanding of machine element and transmission system design, analysis and manufacture. These are complemented by use of the educational material provided by the British Gear Association and a talk by a visiting industry expert.

At least one visit to a transmission manufacturing plant is included. A transmission design project is carried out by students in small groups. In addition, course includes workshops on transmission component failure analysis and finite element modelling of gear systems both carried out by students in small groups.

ECTS units:    12   
Contributing to Course Elements: 12 to ME4-LCTVS Electives

Learning outcomes

Knowledge and understanding

On successfully completing this course unit, students will be able to:

  • Explain the influence of design decisions on the cost, size, weight and reliability of transmission systems.
  • Identify appropriate transmission elements to meet specified objectives.
  • Identify the principal failure mechanisms affecting geared systems, and materials and lubricants capable of resisting them.
Skills and other attributes

On successfully completing this course unit, students will be able to:

Intellectual skills
  • Specify the principal requirements of drive systems for given applications.
  • Design and analyse gears, bearings, shafts and couplings for geared transmissions using standard and empirical methods.
  • Identify the main transmission failure types and recommend appropriate remedial measures.
  • Interpret and improve numerical predictions for gear systems obtained using commercial FE packages.
Transferable skills
  • Demonstrate organisational, problem solving, group work and information technology skills.

Module syllabus

Transmission Systems and Matching: Characteristics of driving and driven machinery, torque and speed transformation, fixed and variable ratio drives. Gearing, belts, chains, friction drives, relative characteristics and cost. Matching.

Gear Geometry: Fundamentals of gearing; Types of gears; Spur gear geometry and kinematics, the involute, pitch and base circles, tooth thickness, basic rack, generation, tip and root diameter, addendum and dedendum, modification factor; Helical gears: lead and helix angles, axial pitch, transverse and normal planes; Bevel gears; Gear pairs: working pressure angle, pitch circles, centre distance, contact ratio; Gear trains.

Gear Design and Stress Analysis: Specification, materials selection, basic design and sizing. Contact and bending stress.

FE Simulations of Gear Systems: Introduction to the use and the interpretation of finite element analysis for gear systems design using ABAQUS. Rim design, teeth profiling, geometrical constraints and boundary conditions. Mesh refinement and mesh grading. Contact and bending stress and transmission error: examples and applications.

Installation:  Rolling and fluid film bearings, rolling bearing life ratings, bearing types and selection; Tooth and bearing loads; Seals; Shafts; Couplings.

Lubrication: Basics of elasto-hydrodynamic lubrication; Oil film thickness and friction in gear contacts; Lambda ratio; Lubricants; Tooth temperatures

Failure Modes: Failure modes in transmission components (gears and bearings); Rolling contact fatigue, pitting, micropitting, scuffing, tooth breakage, overload, fretting; Inspection of real failed components and failure recognition.

Transmission Reliability and Health Monitoring: Power recirculation; Back-to-back rig; Fatigue, life distribution and safe life calculations. Health monitoring: vibration, debris and oil analysis.

Materials and Manufacture: Gear and bearing manufacturing methods; Typical gear and bearing steels; Heat treatment, carburising, nitriding, induction hardening, tempering

Teaching methods

Duration: 21 weeks, Autumn and Spring terms.

Lectures/Tutorials/Workshops: 1 x 2h per week

Other: At least 1 guest lecture from a major automotive company (Autumn term); Industrial visit (Spring Term)

Projects:

1.     Transmission Design Coursework carried out in groups of 3-4 (Autumn and Spring terms): This project is deigned to synthesise much of the material taught in the course and give students the opportunity to apply the learned theory to a real transmission application. Each group is asked to specify and then design a complete gearbox for their chosen application, selected from a list provided. The choice of applications includes a small front wheel drive car, a 4-wheel drive car, a large truck, a high speed yacht, a helicopter tail rotor, a typical wind turbine and others. Help with the project will be provided in scheduled workshops/tutorials at specific intervals during the year. The final report is not to exceed 25 pages in length and it should contain a discussion on the design choices and any compromises made in relation to the specifications. 65 independent study hours. Submission Deadline: to be handed in immediately after the exam. The project is worth 20% of the course mark.

2.     FEA Coursework carried out in groups of 3-4 using ABAQUS (Start of Spring term): This project explores the use of FE methods in prediction of gear stresses. No prior knowledge of FEA is required, the relevant material will be taught directly in the computer room. A significant part of the coursework is concerned with comparing the FEA predictions with those obtained using the analytical methods taught in the first term of the course. Students will be expected to discuss and illustrate the pros and cons of the FEA in gear design. A report of maximum 20 pages in length to be submitted. 65 independent study hours. Submission Deadline: 6th week of Spring Term. The project is worth 20% of the course mark. 

3.     Component Failure Coursework carried out in groups of 3-4 (End of Spring term): This is a hands-on project where students are expected to apply the previously taught theory on damage and failure of transmission components. The practical part of the project is carried out during a scheduled workshop session in the Spring term. A selection of real, failed components (gears, bearings etc.) will be provided, covering all major failure modes. Students are required to examine (using provided microscopes if required) and describe the apparent damage, identify the failure mechanism(s) responsible, discuss the possible reasons for the occurrence of damage and suggest how it may have been prevented. A short report of no more than 6-9 pages (including sketches/photos of damage) to be submitted. 20 independentstudy hours. Submission Deadline: penultimate week of Spring term. The project is worth 10% of the course mark.

Summary of student timetabled hours

Autumn

Spring

Summer

Lectures

17

19

-

Tutorials/Workshops

3

3

-

Total

42

Expected private study time

Average 10 hr per week (including project work), plus exam revision

Assessments

Written examinations:

Date (approx.)

Max. mark

Pass mark

Mechanical Transmissions (3h)

 

This is an OPEN BOOK Examination

May

200

 

Coursework (including progress tests, oral presentations etc.)

Submission date

Max. mark

Pass mark

Submission

Feedback

Gear failure classwork

Written and oral comments

Penultimate week of Spring Term

40

n/a

FE gear analysis

Transmission Design coursework

Written and oral comments

Written and oral comments

6th Week of Spring Term

 Immediately after Exam

80

80

n/a

n/a

Total marks

400

           

Module leaders

Dr Amir Kadiric