Hybrid force and position control of a conducting tri-layer electro-active polymer actuator

Abstract

In this study, the displacement and blocking force of the tip point of a cantilevered electro-active polymer (EAP) actuator has been controlled for a cell injection process which consists of approaching, interacting and leaving steps. A vision-based system is used to acquire the tip displacement data for identifying a transfer function model of the actuator and its position control. Discrete time Proportional-Integral controllers are used to control the position and blocking force. A Smith Predictor is utilized in the vision-based position control system to compensate for the time delay due to image processing. Experimental position and blocking force results prove that the proposed control strategies are effective enough to guide the actuator to undertake the cell injection process. This study contributes to the previously published work from the point of view of simultaneously controlling the position and blocking force of the electroactive polymer actuators and widening their application areas.

Force control of electro-active polymer actuators using model-free intelligent control

“…It is possible to validate the system identification results with other sets of data like sine or ramp signals. However, only step response validation is considered sufficient for this study since the desired force control behavior is generally like step response in many applications of CPAs (Alici and Huynh, 2007;Carpi et al, 2011;Coskun et al, 2017) here to present all validation results for the sake of conciseness of the paper.…”

“…Besides controlling the tip displacement of bendertype CPAs, the blocking force generated by their freeend is required to be robustly and accurately controlled in applications such as micro-nano manipulation, cellinjection, etc. Although there are many works in the literature focusing on modeling and control the CPAs' tip displacement, there is a minimal number of works on the control of blocking force of such actuators (Coskun et al, 2017;Itik et al, 2014). Only quasi-static models (Alici andHuynh, 2006, 2007) are presented to predict the force output of the trilayer CPAs as modeling study which are not convenient to use in applications where the blocking force output of the CPAs needs to be controlled dynamically.…”

“…However, their use in controlling the blocking force output of CPAs is very limited. In our previous work, a linear model obtained by using system identification was used to design a classical PID controller to control the blocking force output of the CPA, which mimics a cell injection process (Coskun et al, 2017). Although the results were successful, the designed controller could not provide the same performance for a long-time working period of the CPA and different CPA sample, due to the dynamic behavior change.…”

Artificial muscles driven by the cooperative actuation of electrochemical molecular machines. Persistent discrepancies and challenges

“…The concomitant physical and mathematical models have been profusely checked by experimental results and technological applications. The temptation is high to treat electro-chemo-mechanical devices as singular cases of electro-mechanical actuators driven by electric fields and described by adaptation of electro-mechanical physical models [36,56,[82][83][84][85][86][87][88][89][90][91][92][93][94][95][96][97][98][99][100][101].…”

Modeling and Experimental Analysis of the Mass Loading Effect on Micro-Ionic Polymer Actuators Using Step Response Identification

“…In recent years, ionic electroactive polymer-based actuators (IEAPs) have attracted global interest among scientists. IEAPs are believed to have potential utility in biomedical applications [7], [8], such as steerable microcatheters [9], [10], microscopy [11], drug delivery [12]- [16], position-controlled microinjection [17], imaging [18], and microsurgical tools [19].…”