LET IT SNOW !!

That's all I-Shovel needs to get to work.

Robot is powered by two independantly controllable motors. When I-Shovel's Robot controller recieves a signal from Snow Sensor, it wakes up and starts moving forward, pushing snow towards an edge until it reaches a perimeter marker or resistance sufficient to stop it.

If the motor is stopped due to the resistance, robot lifts the plow. Then it reapplies the forward thrust, attempting to push collected snow as far as possible. If the robot cannot move any further, the direction of both the motors is reversed, pulling back the robot and then lowers the plow. This operation is called "push-up" and may be repeated a predefined number of times before aborting. Then the robot rotates semi circle, to move on the opposite direction.

If both motors are stopped due to reaching an artificial boundary, robot rotates and makes it move on the opposite direction.

Rotation is done by making one of the wheels turn reverse direction while the other is kept stationary. The motor to be turned changes alternatively, causing the robot to gradually sweep the cleaning area one end to the other. Please see the picture for the cleaning pattern.

This process continues until the robot has made n number of such turns where n equals; length of the cleaning rectangle divided by the length of the plow. Then it goes to a sleep mode until re-activated by snow detector.