Another robot lawnmower

Permanent visual markers are placed at various points on the edges of the yard. The markers would be maintained so that they always look the same and are not visually blocked. The pattern that the mower would later visually follow would be first created by a human pushing the mower on the first cut of the entire yard, while the on board camera took multiple snapshots of the journey. Later, on robotic runs, The camera on the mower would compare and follow pixel patterns on the existing on board memory of visual way points. If an object got in the way the mower would bounce off of the object and use existing robotic mower technology to travel in various directions and hunt for familiar visual way points, the same way humans do, until the proper path was found. Re-mowing previously cut areas could be reduced by a sensor that detected the cutting blade resistance encountered on its journey. When a previously mowed area was encountered, the mower would propel itself to the next path it is to mow, per it's memory. A clock on the mower could assist by comparing the present mowing time and position to the saved time and position in memory. If the operator requests, the mower could send a radio, visual or audible alert advising of abnormalities in its routine. Other features could be added that could detect the climb/descent/bank position of the mower, and compare it to stored data, via a position sensor