Available online
Description
This programme examines British Rail's research into the kinematics of self steering in a coned wheel set. The research forms part of the design of the Advanced Passenger Train.
This programme examines British Rail's research into the kinematics of self steering in a coned wheel set. The research forms part of the design of the Advanced Passenger Train.
| Module code and title: | T100, The man-made world: a foundation course |
|---|---|
| Item code: | T100; 29; 1976 |
| First transmission date: | 22-08-1976 |
| Published: | 1976 |
| Rights Statement: | |
| Restrictions on use: | |
| Duration: | 00:24:35 |
| + Show more... | |
| Producer: | Colin Robinson |
| Contributors: | John Cannell; Alan Wickens |
| Publisher: | BBC Open University |
| Keyword(s): | Advanced Passenger Train; Creep forces; Critical velocity; Efficient rail networks; Hunting problem; Kinematics; Self-steering; Wheel coning |
| Footage description: | Opening shot of the wheels on a railway tank wagon rotating on a roller bed. It displays the technical defect known as hunting. Shot of the advanced passenger train (APT) entering British Rail's technical centre at Derby. John Cannell explains hunting, and introduces the subject of the programme. Aerial film of a passenger train moving through countryside. In voice over Cannell describes the advantages rail has over road travel. Aerial view of motorway interchange, and shots of different motorways at ground level. Shots of a goods train and commentary on the advantages of moving goods by rail. Shots of Heathrow and of planes in flight. These also compared with trains. Cannell explains the necessity for British Rail's research into very fast passenger trains. From beside rail track Cannell describes the amount and cost of track in Britain, and explains why APT must be designed to use existing track. Shot of APT. Problem of increasing speed on nineteenth century track seen as crucial. Cannell uses a model consisting of straight and curved track to explain the importance of research into the wheel set. Four experiments follow: a) a cylindrical wheel -set is run down the track, coming off on a curve. b) a wheel set with 4 to 5 degree coning negotiates the whole track, but attention is drawn to oscillation on the straight section of track. c) a wheel-set with greater ccning still oscillates more on the straight but performs better on the curve. d) a wheel-base is run down the track, showing that two coned wheel sets lose their steering ability when in the wheel-base. Cannell explains why this is so. He shows that the key to steering is the link between yaw and lateral degrees of freedom. From beside a real wheel set Cannell explains the importance of mass, referring to Newton's Third Law. He describes the forces that build up at high speed. Cannell introduces Alan Wickens, director of Laboratories at British Rail's Technical Centre. Wickens explains the nature of creep. He demonstrates the action of longitudinal and lateral creep by means of a spiked wheel run over a lined surface. He uses a chart to explain why creepage increases due to the forces that result from acceleration. Animated diagram showing how creep is manifested in a wheel-set moving at speed. Cannell comments in voice-over. He explains how yaw is induced by creep, and how hunting is produced by the joint action of yaw and lateral creepage. Wickens shows the equations of motion for both lateral and rotational motions of the wheel-set. These are shown by means of a model comprising four blocks, each containing a part of the equation. He briefly explains the use of a computer model in design research. Wickens uses a large model of a wheel-set upon a revolving roller (representing track) to demonstrate the oscillatory effect of a critical speed. He shows how the critical speed can be manipulated by means of adjusting suspension. Wickens shows us the suspension features on APT itself. Film of APT both travelling and stationary. In voice-over Cannell explains the importance of this research into forces acting upon wheel-sets at high speed. He also draws attention to other new design features of APT. He concludes by stating British Rail's plans for APT from inside the train's control cab. |
| Master spool number: | 6HT/72098 |
| Production number: | 00525_5196 |
| Videofinder number: | 2173 |
| Available to public: | no |
