In this paper, we propose a control scheme to deal with unexpected impacts. Impact is inevitable when robot manipulators interact with the environment. Undesirable impacts may induce large interaction forces harmful to robot manipulators and the environment. Impacts may also excite oscillations and even result in manipulator instability. When unexpected impacts occur, a very limited amount of time is available for control. Thus, a reflex mechanism, that emulates the functioning of human reflexes, is included in the proposed scheme. Human reflex is a kind of human action that requires no conscious effort; consequently, it responds to external stimuli without much delay. Simulations are performed to verify the effectiveness of the proposed scheme under a wide range of environmental variations and impact velocities.