How it all began....How it all began....
My First Encounter
It was a hot summer day in late January when I had my first experience of mechanized shearing. In fact, I find it hard to remember if I had a close encounter with sheep before.
Muresk Agricultural College lies about 80 km inland from Perth. A dry wind carried the brown dust and smell of grass baked grey by the sun across the gravel tracks at the bottom end of the campus. The glare of sunlight and radiant heat off the corrugated walls of the shed at the end of the track prepared us for the oppressive heat within. In a small pen beside the shed, three sheep stood still and listless in the rippling waves of heat. Once inside, the dry wind cooled perspiring necks, arms and faces in the relative darkness.
A dozen or so expectant people stood quietly waiting, chatting in groups of two or three. Farmers mostly, I thought, and faces which I was to come to know well during the years which followed.
Standing on the wooden floor at one end of the shed
was an almost alien machine,
far removed from the machines I associate with farming. A two metre high
white frame carried a complex array of machined aluminium, bristling with
precision slides, exotic sensors and bundles of neatly tied coloured wiring.
Below this a shearing handpiece protruded from an articulated mechanism with two shiny wheels to measure
the shape of the sheep. Lower down, a bright blue canvas belt draped loosely
over two long rollers. Grass seeds and tufts of wool lying in the hollow
showed that sheep had been lying on it. White clamps on revolving mountings
carried straps to hold legs at each end of the belt.
At the end closer to the doorway was an electronic
controller - about the size of a two drawer filing cabinet, with the rear
door wide open and two fans blowing warm air into it. A thermometer lay
on top of the cabinet indicating 45°C to a worried Jim Brown, a tall
English engineer, his pale face more accustomed to the chill of winter fogs
at Cambridge. A few more degrees and a hundred or so delicate integrated
circuit modules inside would start cooking themselves to oblivion.
A familiar face emerged from under the machine - Roy Leslie, a young graduate student specializing in automatic process control who had been co-opted to help Jim set up the machine. Roy was an asset, not only for his physical size, but also for his farming background. He took me round the machine pointing out some of the modifications which he and Jim had made just days before. Burnt paint on the pristine white frame showed where a steel section had been cut out to accommodate the longer necks of Australian sheep. Every now and then the machine would come to life as motors hummed and Jim and Roy performed last minute adjustments and checks.
I was introduced to Norman Lewis, nephew of Essington Lewis who was a powerful Australian steel industry figure in the early days. Norman was the power behind the push to build an automatic shearing machine. Marjorie Lewis, the power behind Norman, was with him as she was to be on every occasion a critical decision was to be made. Marjorie thought sheep, felt for sheep, had a perfect affinity with sheep. She knew each of the several hundred ewes and lambs in her nucleus flock by sight. With her gentle wrinkly face and thick curly white hair it was difficult not to sense her feelings for the animal which was being lifted onto the cradle.
This was the moment of truth for them both. In 1972 they had witnessed the collapse of woolgrowing communities in the Wyoming pastoral districts of the USA. Caught in a relentless grip between falling wool prices and rising shearing costs, many had been forced to leave their ranches since the climate and land was too harsh for fat lamb production. Norman and Marjorie saw this as the inevitable fate for the Australian sheep industry too, once the safety margin provided by the higher value of the Australian Merino fleece had been eroded away. ( Merino - the name of the most common sheep breed in Australia).
On their way back to Australia the Lewises had visited the world famous Stanford Research Institute (SRI), world leader in computers and the new science of robotics. Could the Institute build a robot to shear sheep? The reply had been definitely affirmative, provided enough money could be found. The asking price was very, very high but the Lewises were not easily deterred.
The foresight and vision of the Lewises can only be appreciated by realizing that the very first factory robot, the Unimate had only just become a commercial proposition. The now familiar lines of nodding orange robots welding cars together in the huge factories of Detroit and Tokyo were just a dream in the mind of the Unimate's inventors, Joe Engelberger and George Devol. Their robot was a clumsy and crude device which had none of the dexterity or sensitivity needed for shearing sheep.
Richard Paul, a young American graduate student brought up in Sydney, had just finished his PhD thesis at Stanford University, a short stroll away from SRI. He and his colleague Victor Scheinman had developed a more precise robot with a far superior control system to the Unimate. It could follow lines in space, or circles, a clear advance on the crude point-to-point jerks of the Unimate but a far cry from the complex curves and heaving of a living breathing sheep.
Even at Stanford, the first mobile robot was still just a curiosity. It could respond to very simple commands like 'go through the door'. However, every aspect of the robot's environment had to be accurately defined in its program. How could a woolly sheep be accurately defined?
On their return to Western Australia (WA), the Lewises started to collect support for their dream. They were no strangers to long and difficult research projects. They had pioneered the use of clover to boost the capacity of their land from 0.1 sheep per acre to 1 sheep per acre and then had observed the disastrous effects of some clover varieties on pregnant ewes. They found the blood group factor responsible and are still improving fertility levels.
The Lewises formed 'The Southern Districts Sheep Research Council' (SDSRC) with friends and neighbours and collected research funds. 'Ten cents a head' was their slogan. They raised $40,000 and started to look for a firm to carry out the engineering work. Their fellow members of the SDSRC executive were not so fiercely independent, and insisted that pressure be applied to the Australian Wool Corporation and ministers for agriculture in the state and federal governments. They saw that the SDSRC funds would not be enough. Their first formal application was rejected by the Corporation in November 1973. The Corporation favoured the idea of chemical shearing as a long term solution and mechanization of sheep handling in shearing sheds as an intermediate step. Shearing robots were considered 'way out' and impractical.
The Corporation had just set up its own attack on the problem - the 'Australian Wool Harvesting Programme'.
CSIRO , with long experience of research in animal physiology and biochemistry, had suggested chemical shearing. A pill or injection could cause the sheep to stop growing wool for a short time; each wool fibre would have a break or weakened zone so the wool could be pulled off after a few weeks had passed. This occurs naturally with some sheep, and often follows severe stress caused by illness. But they realized that it could take as long as five to ten years to find a safe drug to use.
A second effort was aimed at coordinating and building on the efforts of inventive farmers who had devised machines to help with sheep handling. The Hamilton brothers had built their own production line shearing system on their farm in Victoria and had shorn their flock of 10,000 sheep with it. Tragically, the shed was burned to the ground during the night after an open day. Other farmers, particularly in Western Australia, had been inventing sheep shearing cradles, sheep handling machines to reduce the need for pushing the sheep through races. Farmers all round the country were cooperating and pooling their resources, trying each others' equipment and suggesting new ideas. There was an expectant atmosphere and a 'breakthrough' was thought to be imminent.
The Lewises and their friends were sceptical of chemical and biological defleecing. Marjorie, with her long experience and deep knowledge of fertility and reproduction, knew that a ewe with a broken fleece would not produce a lamb. How could a drug powerful enough to disrupt wool growth not have the same effect? Mechanized shearing still relied on human shearers leaving farmers as vulnerable to union action as they had been since the shearers strikes of the 1890's heralded the union movement in Australia. But Norman also had a more distant vision. He had seen how harvesting machines had revolutionized the wheat industry in Australia and around the world, and was convinced that wool harvesting machines could have the same impact. He saw the involvement of people in shearing as the major obstacle to expansion of the wool industry.
Events in Sydney were soon to prove him right - in part. Justice Mary Gaudron of the Australian Conciliation and Arbitration Commission ruled that the rate for shearing sheep be raised to 43.5 cents, a rise of nearly 50% on the rate for the previous season.
(Australian Conciliation and Arbitration Commission Reports for 21st June 1974 show a rise from $29.90 piecework rate to $31.44. On 9th September, this was raised to $43.50. Comparable rises were awarded to wool classers and shed hands, and shearing costs were further raised by increases in allowances to cover 4 weeks leave with a 17.5% pay loading and a week's sick leave to bring them into line with other workers. Thus over two shearing seasons, with high subsequent cost of living adjustments, the cost of shearing appeared to nearly double.)
Far from sheep and shearing sheds, with just the stroke of a pen, she provided the single most pressing stimulus for robot shearing. The executive of the SDSRC met the next day in Wagin and decided to follow Norman's advice and commit the funds they had raised to go it alone without waiting for the Corporation to act. PA Technical and Science Centre in Cambridge, England, was commissioned to start work on Norman's machine.
The Corporation reacted to this by forming a working group to look at the idea of automating sheep shearing. They sought the views of inventive farmers, engineers, and others, including the Lewises and Lance Lines, an engineer turned farmer in South Australia. Lance had his own ideas for a shearing machine, but was keeping them to himself while collaborating with an independent West Australian inventor, Denton Roberts. They urged the Corporation to support some preliminary experiments with a single automated shearing blow along the back of a sheep.
Finally, in November 1975 with labour costs rising at record rates and wool prices still falling, the SDSRC persuaded the Corporation to back the PATSCentre work with the $250,000 needed to complete the experimental machine. They managed more than that - they retained all rights to the machine. Years were to pass before the Corporation discovered their embarrassing mistake.
Norman's idea was quite novel. Instead of using electronic sensors to detect the skin in contact with the comb, he decided to use a pair of profile measuring wheels which would measure the shape of the sheep, rolling through the wool just ahead of the cutter. The controller stored the profile in its memory and the shearing handpiece was moved by electric motors to follow the stored profile. Within months of starting, the principles had been demonstrated, with a single successful blow along the back of a sheep.
18 months later, his machine was ready.
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September 1997