Worker-Robot Cooperation and Integration into the Manufacturing Workcell via the Holonic Control Architecture
There is no doubt that the rapid development in robotics technology has dramatically changed the interaction model between the robot and the worker. The current robotics technology affords very reliable means to guarantee the physical safety of the worker during a close proximity interaction with the industrial robot. Therefore, new forms of cooperation between the worker and the industrial robot can now be achieved. Cooperative and collaborative robotics are the new fields in industrial robotics, which empowers the idea of close human-robot interaction in manufacturing. The two fields involve the use of a collaborative robot (cobot). The cobot is a social lightweight industrial robot that can cooperate safely with the human co-worker. This is in contrast with the conventional industrial robot that is dangerous to operate in a direct contact with the worker, therefore it often operates in isolation from the worker. The difference between the cooperative and collaborative manufacturing is that in cooperative manufacturing, both the worker and the cobot are sequentially performing separate tasks over the same product in the same shared workspace. However, in collaborative manufacturing, they simultaneously perform the shared task. Cooperative manufacturing is the main focus of study in this dissertation. Cooperative manufacturing adds a new dimension to the production system, which promotes the agility and the flexibility of the production model. The fast success of cooperative manufacturing is a natural result of the varying production demands, which requires high level of customizability. Gathering the worker and the cobot in the same manufacturing workcell can provide this production customizability. This is because the worker does not only add the high flexibility of taking the proper actions based on the production demands, but also the worker is able to use his natural senses intuitively to form complex solutions during the real-time of production. Simultaneously, the cobot is a reliable resource in terms of speed, accuracy, and weight lifting. In other words, cooperative manufacturing supports the use of the cobot as a smart tool by the worker, to increase the efficiency and accelerate the productivity of the manufacturing. Cooperative manufacturing is a new field of research, which addresses new challenges beyond the physical safety of the worker. Those new challenges appear due to the need to connect the worker and the cobot from the informatics point of view in one cooperative workcell. This requires developing an appropriate manufacturing control system, which fits the nature of both the worker and the cobot. Furthermore, the manufacturing control system must be able to understand the production variations, to guide the cooperation between worker and the cobot and adapt with the production variations. Designing a manufacturing control solution that enables the cooperation between the worker and the cobot is the main purpose of this dissertation. The design of this manufacturing control solution has been done over three levels. The first level is the control software component. In this level, an autonomous three layers software component is developed to link the worker and the cobot to the control solution. The three layers of the software component are physical, communication, and reasoning. The second level of the solution is the cooperative workcell where other sources of information are represented along with the worker and the cobot such as the product and the manufacturing operations and tasks. Finally, the last level of the solution is the industrial enterprise where more than one cooperative workcell must coordinate together. Ultimately, three case studies have been introduced to test the viability and the feasibility of the proposed control solution.
Rostock, Univ., Diss., 2018