the only problem i found
the only problem i found with sharp sensors is that they loose the object at some points as you can see in the video.Maybe because of the unstable readings from the sensors .but this problem can be overcomed using PIR sensors along i guess.
Eureka!
Combine Splatbot, this bot, some smooth object tracking, and mount it all on some sort of gun-sentry type platform and I think I have something to keep the rodents away from my vegetables at night! Good stuff, m8.