actuators Article Mechanical Design and Performance Analyses of a Rubber-Based Peristaltic Micro-Dosing Pump Thomas Zehetbauer 1, *, Andreas Plöckinger 1 , Carina Emminger 2 and Umut D. Çakmak 2, *   Citation: Zehetbauer, T.; Plöckinger, A.; Emminger, C.; Çakmak, U.D. Mechanical Design and Performance Analyses of a Rubber-Based Peristaltic Micro-Dosing Pump. Actuators 2021, 10, 198. https:// doi.org/10.3390/act10080198 Academic Editor: Andrea Vacca Received: 20 July 2021 Accepted: 17 August 2021 Published: 19 August 2021 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affil- iations. Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). 1 Linz Center of Mechatronics GmbH (LCM), Altenbergerstrasse 69, 4040 Linz, Austria; andreas.ploeckinger@lcm.at 2 Institute of Polymer Product Engineering, Johannes Kepler University Linz, Altenbergerstrasse 69, 4040 Linz, Austria; carina.emminger@jku.at * Correspondence: thomas.zehetbauer@lcm.at (T.Z.); umut.cakmak@jku.at (U.D.Ç.) Abstract: Low pressure fluid transport (1) applications often require low and precise volumetric flow rates (2) including low leakage to reduce additional costly and complex sensors. A peristaltic pump design (3) was realized, with the fluid’s flexible transport channel formed by a solid cavity and a wobbling plate comprising a rigid and a soft layer (4). In operation, the wobbling plate is driven externally by an electric motor, hence, the soft layer is contracted and unloaded (5) during pump-cycles transporting fluid from low to high pressure sides. A thorough characterization of the pump system is required to design and dimension the components of the peristaltic pump. To capture all these parameters and their dependencies on various operation-states, often complex and long- lasting dynamic 3D FE-simulations are required. We present, here, a holistic design methodology (6) including analytical as well as numerical calculations, and experimental validations for a peristaltic pump with certain specifications of flow-rate range, maximum pressures, and temperatures. An experimental material selection process is established and material data of candidate materials (7) (liquid silicone rubber, acrylonitrile rubber, thermoplastic-elastomer) are directly applied to predict the required drive torque. For the prediction, a semi-physical, analytical model was derived and validated by characterizing the pump prototype. Keywords: hydraulic pump; micro-dosing; peristaltic; hyper-elasticity; viscoelasticity; holistic design methodology; elastomer compound 1. Introduction Pumps have a broad field of application and can be considered as energy transducers, converting primary kinetic energy (e.g., linear, or rotational motion of a rigid body) to hydrodynamic energy [1]. A simplified view on the technical side of a pump reduces it into three main components which describe the operation principle [hydraulic pump very abstracted]: housing with fluid in- and outlet port, moving component(s) and transmission gear to drive the moved part via the primary energy source. Based on the operation principle hydraulic pumps, beside some exceptions like “the hydraulic ram” [2] which uses the water hammer effect [3] as primary energy source, can be categorized into two main groups, namely centrifugal pumps [4] and (positive) displacement pumps. Schmitz and Murrenhoff [5] gives a good overview of hydraulics in general. Centrifugal pumps have an open fluid connection from in- to outlet port, the impeller accelerates the fluid due to its rotational movement which causes centripetal forces (actio); in other words: the fluid is moved due to its centrifugal force caused by the impeller (reactio). In contrast to that, the in- and outlet ports of displacement pumps are disconnected by a sealing which is considered as “leak-free” flow, so the fluid volume “the displacement” is encapsulated and transported by the motion per turn. Some pumps of this kind have multi-sectioned and even parallel, and phase shifted displacement to smooth the flow rate and, consequently, reduce pulsations. The most common types of displacement pumps are gear pumps, screw Actuators 2021, 10, 198. https://doi.org/10.3390/act10080198 https://www.mdpi.com/journal/actuators