For better manipulability, a criterion in the form of a quadratic function is presented for the self-motion planning (SMP) of redundant manipulators with no target-configuration assigned. Such SMP scheme could automatically select the desirable configuration so that the manipulator could be more flexible and maneuverable. As physical limits generally exist in actual redundant manipulators, both joint limits and joint velocity limits are taken into consideration in the presented SMP scheme for practical purposes. Computer simulations based on two types of multi-link planar robot arms substantiate the efficiency and reliability of the presented scheme. Moreover, theoretical analysis of the presented quadratic performance index is conducted and proved via two different approaches, i.e., gradient-descent and Zhang et al’s neural-dynamic methods.