Despite recent advances in robotics around autonomous machines, machines really capable of giving a real to humans, as part of everyday life, remains limited. On the other hand, the animal, especially dogs, has shown for many years the capacity to complete the man in his life in daily tasks, such as aid for service dogs, or in exceptional event such as avalanche or earthquakes intervention, or in professional life to search for drugs, for example. Nevertheless, each system, robot or dog has its own limits, for example: a step or a hole can be fatal to a robot, a cat turns "mad" a dog. The actual idea is to take best of both entities to increase the performance of the couple animal / robot. In this context, the subject requires extensive research in particular on the development of interaction, communication or cooperation between a robot and a dog. The Cochise project proposes a modest focus of this research, on a particular set of dogs: service dogs for people with mobility impairments. Service dogs assist the human in the gestures of everyday life and for this purpose the problem is clearly identified. In this context, we propose to design a robot to act on and with the service dog, to build a "couple" with high performance in regard to the problem. The machine will become a mediator robot that allows on one hand to "understand" the state of the dog and retransmit it to the man, and on the other hand to enable autonomous robot via the trigger sequences of behavior on the dog. The question underlying the Cochise project is: how far a dog he will accept to obey to a robot? and what type of robot should be designed for this?. The project Cochise is twofold: firstly to increase the knowledge on the interactions in an animal / robot system and to achieve an experimental development that could quickly become a mainstream product. For this project we bring together the skills of users and trainers of service dogs , people specialized in robotics sensors and actuators for the realization of the robot and finally reseachers specialized in human / machine interface and architectures to build an operational device for the user.