5 January 1996

LESS STRESS ALL ROUND

Six seasons on, Mr Gorringes monitoring system is still working well, despite expiry of the original camera. A replacement added some £200 to the original £400 parts cost.

Controls are by Mr Gorringes bed, and the monitor sits alongside. "We calve between Jan 1 and Mar 31," he explains. "I look at the cattle last thing at night. If I see an animal which needs watching I can go to bed, set the alarm and check it at any time without getting up – the picture shows plenty of detail.

"The yard is lit all night, and the cattle dont bat an eyelid when the extra lamp comes on. Remote monitoring means less stress for them and less stress for me. I tend to watch them more often than I otherwise would, yet lose less sleep doing it. And although I cant quantify the benefits in monetary terms, the system has certainly reduced mortality at calving."

Single eye sees more

Cameras can save lives. Andrew Pearce visited a Herefordshire farmer who has devised his own remote control stock monitoring system

MOST people wanting to watch stock by closed circuit television (CCTV) buy a system off the shelf. Its the logical thing to do.

So back in 1990 when Philip Gorringe decided to monitor calving in his 130-cow single suckler herd from the house, he did the logical thing and invited a specialist out to Lower Blakemere Farm, Blakemere, Herefordshire. No problem, the man said: Four panning cameras, one at each corner of the yard, will give cover.

But Mr Gorringe was not convinced. If a round feeder or other animals hid the target beast from the closest camera, the other units might be too far away to give a clear picture. And if he couldnt be sure of what he was seeing, then the whole system would be a waste of money.

The answer seemed to be a travelling camera, able to track the length of the building and look round obstructions. But with nothing like it on the market, the only option was to make his own.

Calving yard layout helped. Down the centre of the 32m-long (105ft) building runs a raised feeding platform, providing a bovine-free area from which a single mobile camera could survey the whole scene.

Eye in the sky

The initial demo had shown that a black-and-white camera, tungsten floodlighting and a dedicated CCTV monitor provided excellent picture quality. A security firm provided the necessary hardware for around £200, and Mr Gorringe set about making it all work.

The first job was to make the camera mobile. Camera, pan unit and a 500W floodlight are all mounted on a wheeled carriage. This travels along a track made from 200mm (4in) channel, suspended from the roof rafters and covering most of the buildings length.

A cable loop sits over a pulley at each end of the track, with the carriage closing the loop. Depending on which way the pulleys turn, the carriage is pulled one way or the other.

Searching around for a motor, a stroke of luck produced a secondhand reversible single-phase unit from a profile cutter. Driving one pulley, its 8rpm shaft speed gives full carriage traverse in about one minute.

Secondary smaller carriages carry loops of cable serving the camera and floodlight; these first fan out, then regroup as the main carriage moves away and back.

Fun with relays

Mr Gorringe saw that by using relays and a simple switch in the house, he could drive the motor in either direction and thus reverse the carriage manually. But he wanted the camera to track to and fro automatically, and that called for a little more thought.

He ended up with an arrangement using two relays. These are wired so that as one is opened by the carriage touching a microswitch at the end of the track, the other closes to reverse the motor and drive the carriage back. The process repeats itself when the carriage arrives at the far end, so the camera shuttles to and fro automatically.

Two boxes control operations back at the house. The pan unit came with its own remote control which is used as is. Floodlighting and camera travel are directed from a second box carrying switches for automatic or manual operation. And as all functions are worked through 12v relays mounted in the barn, wiring from the house to yard only carries low voltage rather than mains power.

Left: A reversible motor from a profile cutter drives one pulley at 8rpm – enough to move camera the length of the building in about one minute. Right: Cable loops hang from smaller carriages on the beam, expanding as camera (top left) moves away from drive end. Relays control mains power close to the motor.

Left: No more stumbling across a windy midnight yard for Herefordshire farmer Philip Gorringe – CCTV brings calving action to his bedside. Right: High resolution from the purpose-made monitor shows plenty of detail.