13.1   ROBOCOW—A MOBILE ROBOT FOR TRAINING HORSES

The National Centre for Engineering in Agriculture received a startling
project proposal concerning a “robot cow” that could fool a horse. As discussions
progressed, it rapidly became clear that the design requirements
would be extremely hard to meet. The purpose was the training of horses for
cutting contests, where horse and rider must control the movement of a young
cow. The business proposal was made by an acknowledged “cutting
champion.”

In heading off a young cow that is trying to rejoin the herd, the partnership
of horse and rider depends entirely on the ability of the horse to recognize
and anticipate the intentions of the cow. In training the horse, it has been
usual to use a “borrowed” calf—or two, or three or more.

As fast as the horse learns, so the cow also learns and very soon refuses
to cooperate. So, to train one horse takes the use of many cows and considerable
expense. A robot cow, on the other hand, would be consistent and predictable
by the rider if not by the horse.

Robocow, as it was quickly named, must perform a memorized sequence
of actions, so that with no more than a two-button controller the horse rider
can select, start, pause, or resume the cow’s performance. In addition, it is
important that when completing a sequence designed to bring it to the starting
point, the cow can repeat the sequence several times before large positional
errors are built up.

Some of the sequences can be preprogrammed during manufacture, but
there is also the need to provide the ability to memorize special individualized
routines on the farm. For this, a standard radio-control joystick system is
used.

At the outset, the mechanical performance requirements were challenging,
to say the least. The cow must reach a speed of 20 km/h with an acceleration
of several meters per second per second. The terrain was specified as “beaten
earth.”