There's SAFETY in Comfort
Page 41
If you've noticed an error in this article please click here to report it so we can fix it.
says P. A. C. Brockington, AM .1.14 ech.E. AT the 1948 Commercial Motor Show it was evident that designers had responded to the demand for greater cab comfort, in the literal sense by providing better seating accommodation and in the operative sense by improving controls, lighting and so on. I recently had the opportunity of obtaining the opinions of a number of long-distance haulage drivers on these matters, and whilst it was agreed that present tendencies indicated a realistic approach to drivers' requirements, it was apparent from the complaints heard that most heavy vehicles are needlessly tiring to drive.
Conclusions drawn from the conversations are given in the following summary, and it is, perhaps, pertinent to add that, in some instances, the drivers had just completed 12-hour day or night journeys.
The priority requirement is good vision. The best modern cabs are adequate in this respect, but further improvements could be made. An undivided, deep windscreen with thin pillars is desirable, and the possibility of fitting a car-type, curved windscreen should he considered. Reduction in driving fatigue and greater safety are contingent advantages of any improvement that can be introd need.
A fully adjustable seat is a necessity when a vehicle is handled by a number of different drivers, and is desirable in any vehicle. A driver sitting in a strained position will tire quickly, and his vision may be reduced.
Sliding doors are beneficial in two
ways. First, both doors may be opened to increase the angle of vision to each side and to the rear without danger of damage to them or of c.a us ing injury to others. Secondly, in very hot weather, they may be kept open when travelling.
When swinging doors are fitted, transparent panels in the side quarters at floor level provide a muchneeded aid to manceuvring.
The gear lever should be as close as possible to the steering wheel to save unnecessary hand movements and to reduce the effort needed to move the lever.
The accelerator pedal should be broad and long for foot and ankle comfort. Every driver questioned mentioned this requirement. Ample dimensions give the necessary variety of operating positions for the foot. surfaces and durable mats. Con
venient pockets for holding cleaning materials help to encourage a lastminute polish-up when a driver is waiting for his load or to refuel.
Mirror brackets and arms are frequently too flimsy to resist vibration. The view becomes blurred at critical vibration periods and the mirror works loose.
Although the amount of leg-room is largely determined by chassis design, as distinct from cab layout, as much "stretching space" as possible should be given." Most forwardcontrol cabs give sufficient room, but many long-legged drivers of normalcontrol vehicles complained that leg restriction was generally the main cause of premature fatigue. A hand throttle as an alternative to foot control would help on long journeys.
The desirable cab characteristics outlined are based on widely
accepted views. Many other suggestions were made and discussed regarding hand-brake positioning, heat insulation, interior lighting, the provision of door locks and the storage of tools.
When asked to give their views on steering control, most of the drivers used the word "feel " in describing
a vehicle that handled well. The word cannot be technically analysed, but undoubtedly reduction of...friction to a minimum, in preference to increasing the box ratio, is contributory to comfortable "feel."
To an experienced driver it will indicate an incorrectly positioned load, an under-inflated tyre or a weak spring. The possibility of employing power steering on heavy vehicles appealed to many of the drivers, but as one of them put it, " you couldn't• feel the steering then."