Eniko T Enikov
Associate Professor, BIO5 Institute
Professor, Aerospace-Mechanical Engineering
Primary Department
Department Affiliations
(520) 621-4506
Work Summary
Dr. Enikov's area of expertise is the design of micro-actuators, MEMS devices, and sensors. Ongoing projects include the production of Inflatable Drug-Delivery Stents through the process of Dynamic Stabilization of Electro-Spinning. The research will examine theoretically the feasibility of trapping charged fibers and will establish the required trapping parameters.
Research Interest
Dr. Enikov's area of expertise is the design of micro-actuators, MEMS devices, and sensors. After completion of his training, he established the Advanced Micro- and Nanosystems Laboratory at the University of Arizona, where they have carried out numerous research projects involving precision assembly of micro-systems under optical feedback, development of wet actuators using ion-exchange polymers, pressure sensors, and accelerometers. In the last 8-years, his research has applied micro-technology to the development of medical devices. More specifically, they have developed a through-the-eye lid tactile tonometer capable of estimating intraocular pressure using an array of MEMS sensors. A second invention pertains to the development of an implantable ventricular peritoneal shunt with flow sensing capabilities. The present project represents a major focus of his laboratory. They have completed several early-stage studies on tactile tonometery supporting the present application. Given Dr. Enikov's technical background and prior effort in the area of tactile tonometery, he believes he is uniquely qualified to lead the proposed effort.


Enikov, E. T., Minkov, L. L., & Clark, S. (2005). Microassembly experiments with transparent electrostatic gripper under optical and vision-based control. IEEE Transactions on Industrial Electronics, 52(4), 1005-1012.


This paper describes the assembly experiments conducted with a novel miniature assembly cell for microelectro-mechanical systems. The cell utilizes a novel transparent electro-static gripper and uses several disparate sensing modalities for position control: computer vision for part alignment with respect to the gripper, a fiber-coupled laser, and a position-sensitive detector for part to assembly alignment. The assembly experiments performed indicate that the gripping force and stage positioning accuracy of the gripper are sufficient for insertion of micromachined parts into slots etched in silicon substrates. Details of the cell operation, the control algorithm used, and their limitations are also provided. Potential applications of the developed assembly cell are assembly of miniature optical systems, integration of optoelectronics, such as laser diodes with CMOS, and epitaxial lift-off of thin films used in optoelectronic devices. © 2005 IEEE.

Szabo, Z., Ganji, M., & Enikov, E. T. (2011). Development of voice-coil micro-actuator for 3-D virtual tactile displays. ASME 2011 International Mechanical Engineering Congress and Exposition, IMECE 2011, 7(PARTS A AND B), 1027-1033.


An electromagnetic micro-actuator operating on the principle of voice-coil actuators is presented. Using finite element analysis of several conceptual designs of actuators [1-3], it was established that the voice-coil type device (where the coil is the moving part) has most beneficial characteristics for the envisioned application. These include sufficient force over a relatively large distance, allowing tactile stimulation of surfaces with irregular shape, fast response, and small footprint that matches the density of the tactile sensory neurons in the finger. Finite element analysis based on ANSYS was used to determine the dimensions of the components of the actuator. In comparison to earlier designs [3-5], this novel device has smaller sizes (2.28 mm in diameter and 7 mm in length), which makes it suitable for use in an array to be worn on the fingertip. Based on the static measurements of a test prototype, it is estimated, that the micro-actuator can produce at least 26 mN of repulsive force on the fingertip over a stroke of 2100 μm with a peak force of 34 mN. The driving circuit operates with 13.5V and generates a vibration frequency of up to 265 Hz without significant change of the force-displacement characteristics. In the higher frequency range (above 100 Hz) the actuator provides at least 15 mN of force over a stroke of 2300 μm, and a peak force of 21mN. The perceivability of the device on human fingertip approves the expectations drawn from the fact that all of the above parameters meet the required values of the thresholds of the human perception known from [4] and [5]. Due to its increased stroke, the voice-coil micro-actuator proved to be very suitable for the envisioned application allowing contact with the curved surface of the fingertip. Copyright © 2011 by ASME.

Deng, K., Enikov, E. T., & Polyzoev, V. D. (2009). Development of a shape conveying interface based on tactile feedback. 2009 ICME International Conference on Complex Medical Engineering, CME 2009.


A shape conveying interface based on tactile feedback is developed in this paper. To deliver the reference shape, the electromagnetic (EM) position sensors and wearable permanent magnet based EM actuator are used to provide the estimated 3D image by the user's scanning. Principle and experimental results of EM position measurement are provided. ANSYS simulation is used to design a proper dimension of solenoid to drive the permanent magnet actuator. With the designed actuator, the 63.57 mN actuation force at peak current is estimated from measured force-current curve. 50-Hz operation which has been shown to be optimal working frequency is used to produce vibratory stimulation to user's finger. The shape perception experiments performed by 2 volunteers showed that majority of shapes are able to be delivered. More cues may be incorporated in order to improve successful rate of the shape delivery. ©2009 IEEE.

Enikov, E. T., & Seo, G. S. (2005). Experimental analysis of current and deformation of ion-exchange polymer metal composite actuators. Experimental Mechanics, 45(4), 383-391.


In this paper we describe the experimental analysis of a novel ion-exchange polymer metal composite (IPMC) actuator under large external voltage. The experimental analysis is supplemented with a coupled thermodynamic model, which includes mass transport across the thickness of the polymer actuator, chemical reactions at boundaries, and deformation as a function of the solvent (water) distribution. In this paper, the case of large electrode potentials (over 1.2 V) has been analyzed experimentally and theoretically. At these voltage levels, electrochemical reactions take place at both electrodes. These are used in the framework of overpotential theory to develop boundary conditions for the water transport in the bulk of polymer. The model is then simplified to a three-component system comprised of a fixed negatively charged polymeric matrix, protons, and free water molecules within the polymer matrix. Among these species, water molecules are considered to be the dominant species responsible for the deformation of the IPMC actuators. Experiments conducted at different initial water contents are described and discussed in the context of the proposed deformation mechanism. Comparison of numerical simulations with experimental data shows good agreemenent. © 2005 Society for Experimental Mechanics.