Position-controlled servomechanisms are the core elements of flexible manufacturing plants, primarily utilized to actuate robotic systems and automated machines. To match specific torque and costs requirements, typical servomechanism arrangements comprise precision reducers, which introduce motion errors that heavily limit the final performance achievable. Such errors are complex to model and depend from speed, dynamic loading conditions and temperature. Accurate characterization is fundamental to develop digital twins and advanced control strategies aimed at their active prediction and compensation. To properly assess the servomechanisms behavior and elaborate high-fidelity virtual models, instrumented test rigs have been proposed which can replicate the time-varying working conditions encountered in real industrial environments. In this context, the present paper reports about a novel engineering method for developing an active loading apparatus, namely a programmable mechatronic device that can deliver custom loads in a highly dynamic manner. The proposed system, consisting of a secondary servomotor and related rotating vector reducer, is integrated and synchronized within an existing instrumented test rig and is controlled in torque mode via a programmable logic controller. The paper mainly focuses on the description of the implemented closed-loop control and on the related tuning and calibration processes, demonstrating that the proposed solutions avoid important measurement errors that could compromise the final effectiveness of the system. The study finally explores the potential benefits of introducing a filter to further enhance system performance. At last, to prove the importance of stabilizing the rig and demonstrate the influence of the control parameters on its measurements, a standard test aimed at assessing the reducer transmission error is conducted adopting different parameter settings.

中文翻译：

---

设计和实施主动负载测试台，用于工业应用中伺服机构的高精度评估


位置控制伺服机构是柔性制造工厂的核心元件，主要用于驱动机器人系统和自动化机器。为了满足特定的扭矩和成本要求，典型的伺服机构布置包括精密减速器，这会引入运动误差，严重限制可实现的最终性能。此类误差建模起来很复杂，并且取决于速度、动态载荷条件和温度。准确表征是开发数字孪生和旨在其主动预测和补偿的高级控制策略的基础。为了正确评估伺服机构的行为并精心制作高保真虚拟模型，已经提出了可以复制真实工业环境中遇到的时变工作条件的仪表化测试台。在此背景下，本文报告了一种开发主动加载装置的新型工程方法，即一种可以以高动态方式提供定制负载的可编程机电一体化装置。拟议的系统由辅助伺服电机和相关的旋转矢量减速器组成，集成并同步在现有的仪表化测试台中，并通过可编程逻辑控制器在扭矩模式下进行控制。本文主要侧重于对已实施的闭环控制的描述以及相关的调谐和校准过程，表明所提出的解决方案避免了可能影响系统最终有效性的重要测量错误。该研究最后探讨了引入滤波器以进一步提高系统性能的潜在好处。 最后，为了证明稳定钻机的重要性并证明控制参数对其测量的影响，采用不同的参数设置进行了旨在评估减速器传动误差的标准测试。