Redundant cascade manipulators actuated by pneumatic bellows actuators are passively compliant, rugged and dexterous which are qualities making them exceptionally well suited for applications in agriculture. Unfortunately bellows actuators are notoriously difficult to precisely position. This paper presents a novel control algorithm for the control of a parallel platform actuated by pneumatic bellows actuators, which is serving as one module of a cascade manipulator. The algorithm combines a feed-forward controller and a variable gain I-controller. The feed-forward controller was designed using experimental data and two regression steps to create a mathematical representation of the data. The gain of the I-controller depends linearly on the total reference error, which allows the I-controller to work in concert with the feed-forward part of the controller. The presented algorithm was experimentally verified and its performance was compared with two controllers, an ANFIS controller and a constant gain PID controller, to satisfactory results. The controller was also tested under dynamic loading conditions showing promising results.

翻译：由气压波纹管执行器驱动的冗余级联机械臂具有被动柔顺、坚固且灵活的特性，使其特别适用于农业应用。然而，波纹管执行器在精确定位方面存在显著困难。本文提出一种新型控制算法，用于控制作为级联机械臂模块之一的气压波纹管驱动并联平台。该算法结合了前馈控制器与变增益I控制器。前馈控制器基于实验数据并通过两步回归法构建数据的数学表征。I控制器的增益与总参考误差呈线性关系，从而使I控制器能够与前馈控制器协同工作。所提算法经过实验验证，并与ANFIS控制器及恒增益PID控制器进行性能对比，取得了满意结果。此外，该控制器在动态负载条件下进行了测试，显示出良好的性能。