Attractive regions in the environment [motion planning]

In general, it is believed that the sensor-less manipulation can only achieve low-precision or simple tasks. However, it is not always true. We point out that there are two attractive regions. In the motion space of the dynamic system with an active control system, which bases on sensory feedback, there is an attractive region, which forces the system to follow the nominal trajectory with the uncertainty of the system. At the same time, there is another attractive region, which widely exists in the configuration space of the dynamic system under constraints from environment. Both of these two attractive regions can be used to eliminate the uncertainty of the system states in order to achieve high-precision tasks. This paper focuses on the effective use of attractive regions in the environment to eliminate the uncertainty. However, in general, sensors are still useful and play an important role in many systems. Thus this work is related to the approach on the relationship between required information and strategy investigation.