Electrodes in a Plane with Fix-Ended Gel

For verification of this hypothesis, we applied voltages to four electrodes in a line and observed the movements of the simulated and real gel. Each electrode in this case is 4 [mm] in width, 20 [mm] in length. The space between two adjacent electrodes in the array is 2[mm]. The strip of the gel and the electrode array were parallel to each other. The space between the gel and the array is 15[mm]. We applied the following set of voltages to the electrode array from left to right  

The left side of the gel strip was fixed while the right side was free. 

The top figure shows the initial state. The middle figure shows the shape of the gel after applying the electric field for 30 seconds. The bottom figure shows the gel state after applying electric field for 60 seconds. Although the speed of the motion was slow, the results show that large transformations are possible to use a linear array of electrodes. 

The gel bends towards the anode electrodes, and away from the cathode electrodes. This is because an anode repels surfactant molecules, which adhere to the surface of the gel on the same side as the electrode. In contrast, the cathode electrode attracts the surfactant molecules away from the gel surface. The adsorption speed is much faster than desorption speed, which causes the molecules on the surface to accumulate. Hence the curvature becomes larger. 

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Fig. 5.4. New configuration of the electrodes in a plane with fix-ended gel. The electrode above the gel is cathode for a) and anode for b).

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