Design of Energy Efficient Mechatronic Systems based on Automated Controller Synthesis and Trajectory Planning

由于不断上涨的能源价格，机电系统的能效，例如在工业制造中，是一个越来越重要的因素。在多轴系统中节约能源的一种可能性是重复使用单个机械手轴的恢复制动能量，以同时为系统中的其他轴提供能量。许多多轴系统，例如自动化生产系统，已经提供了支持这种重复使用的技术要求-挑战在于开发以节能方式协调过程的优化软件。我们已经开发出规划多轴系统节能轨迹的方法。单轴和/或多轴机械手的点到点运动的能量最优运动轮廓可以在考虑移动载荷、摩擦效应等因素的情况下计算出来。现有的方法已经产生了显著的节能效果。然而，在组合了多个单轴和多轴机械手的系统中，节能潜力目前还不能得到充分发挥。这是因为现有的方法不能在离散控制过程的层面上考虑可能的运动序列的重新排列。这将导致优化问题的复杂性急剧增加。此外，目前的方法不能考虑可能对运动序列施加的复杂的、有时是关键的要求。因此，在这个跨学科的研究项目中，我们计划开发一种新的设计节能机电系统的方法，将能量优化轨迹规划方法和离散控制器自动综合方法结合起来。这种方法应该已经在离散控制过程的设计中使用。在这里，工程师必须考虑离散系统行为的所有要求；但同时，他们不应该过度约束可能的替代控制序列。我们通过在以前的工作中详细说明的规范方法来支持工程师完成这项任务，该方法允许他们以场景的形式描述系统可以、必须或不能做的事情。根据这样的规范，我们可以通过算法计算有效的离散控制器实现。我们对这种方法进行了扩展，通过最初包含单个轴运动消耗和再生的能量的粗略假设，我们可以合成节能的离散控制器。如果在此过程中必须在看起来类似高效的备选运动序列之间做出决定，我们计划集成节能轨迹规划方法，以基于更详细的模型来选择最有效的运动序列。通过在不同层面上考虑系统行为，使工程师能够更广泛地挖掘节能潜力。我们将基于一个实例研究来开发和评估这种设计方法。

Due to constantly rising energy prices, the energy efficiency of mechatronic systems, e. g. in industrial manufacturing, is an increasingly important factor. One possibility for energy savings in multi-axis systems is the re-use of recuperated braking energy of single manipulator axes to simultaneously supply other axes in the system. Many multi-axis systems, e. g. automated production systems, already provide the technical requirements to support such a re-use - the challenge lies in the development of optimized software that coordinates the processes in an energy-efficient way. We already developed methods for the planning of energy-efficient trajectories of multi-axis systems. Energetically optimal motion profiles for point-to-point movements of single- and/or multi-axis manipulators can be calculated under consideration of moving loads, friction effects, etc. The existing methods can already yield significant energy savings. However, in systems that combine multiple single- and multi-axis manipulators, the energy saving potential can currently not be fully exploited. The reason is that current methods cannot consider a possible rearrangement of movement sequences on the level of the discrete control process. This would lead to an explosion in the complexity of the optimization problem. Moreover, the current approaches cannot consider the complex and sometimes critical requirements that may be imposed on the movement sequences. In this inter-disciplinary research project, we therefore plan the development of a new method for the design of energy-efficient mechatronic systems, which couples the methods for the energy-optimized trajectory planning and methods for the automatic synthesis of discrete controllers. This method shall already be employed during the design of the discrete control process. Here, the engineers must consider all the requirements of the discrete system behavior; but, at the same time, they should not over-constrain possible alternative control sequences. We support engineers in this task by a specification method, which was elaborated in previous work, allowing them to describe, in the form of scenarios, what a system can, must, or must not do. From such a specification, we can then compute valid discrete controller implementations algorithmically. We extend this approach such that, by initially including coarse assumptions of energy consumed and regenerated by individual axis movements, we can synthesize energy-efficient discrete controllers. If during this process it must be decided between alternative movement sequences that appear similarly efficient, we plan to integrate the energy-efficient trajectory planning approach to choose the most efficient movement sequence based on a more detailed model. By considering the system behavior on different levels, we will enable engineers to more extensively exploit energy saving potentials. We will develop and evaluate this design methodology based on an example case study.