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Theoretical force curve for a single fiber ESC device acting on a flat surface, consisting of an approach phase and a release phase.
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An electrostatic chuck (ESC) is a type of reversible dry adhesive which clamps objects by means of electrostatic force. Currently an ESC is used only for objects having flat surfaces because the attractive force is reduced for rough surfaces. An ESC that can handle objects with rough surfaces will expand its applications to MEMS (micro electro mech...
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... force is positive in the upward direction from the object's surface. Given the mechanical model of the fiber, we are able to construct a force curve mathematically as shown in figure 5. The force curve signifies the relationship between f att with respect to the displacement of the device base, Z, for a single fiber ESC device when approaching a flat-surfaced object upon applying a voltage. ...
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... the electrostatic force becomes constant once the fiber makes contact with the object, the characteristics of the attractive force are significantly dependent on the elastic force. Therefore, figure 5 shows only the portion with elastic force, from which the behavior of the fiber during the approach and release phases can be analyzed. ...
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... jump-to-contact phenomenon from an energy perspective is discussed thoroughly in Saito et al [21]. The displacement in which contact occurs, Z cont , is indicated in the horizontal axis of figure 5. ...
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... occurs when f k during the release phase is larger than the maximum attractive force, or f k > f kmax . Z det in the horizontal axis of figure 5 indicates the displacement when detachment occurs. When utilizing a fiber with compliance, it can be understood that the maximum attractive force is obtained in the release phase, rather than in the approach phase. ...
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... it was also observed that during the release phase, the fiber maintained contact with the object before detachment, which resulted in the largest attractive pressure in the cycle. These two physically-observed phenomena are consistent with the behavior of the theoretical force curve as shown in figure 5 and are as was discussed by Saito et al [21]. The maximum attractive pressure obtained was −852 Pa during the approach phase and −968 Pa during the release phase. ...
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... expression for the electrostatic force is obtained by deriving the equation for a model of a capacitor with two different dielectric substrates in series. The force is positive in the upward direction from the object’s surface. Given the mechanical model of the fiber, we are able to construct a force curve mathematically as shown in figure 5. The force curve signifies the relationship between f att with respect to the displacement of the device base, Z , for a single fiber ESC device when approaching a flat-surfaced object upon applying a voltage. Since the electrostatic force becomes constant once the fiber makes contact with the object, the characteristics of the attractive force are significantly dependent on the elastic force. Therefore, figure 5 shows only the portion with elastic force, from which the behavior of the fiber during the approach and release phases can be analyzed. If a voltage is applied when the fiber tip is far enough away from the object, it will approach the surface because of the electrostatic force. In this phase, there is a point where f k + f e = 0, which keeps the fiber at a stable position. If the fiber is brought closer to the object, the fiber will lose its stable energy point [21], and spontaneously make contact with the object’s surface. The contact occurs when f e > − f k . This jump-to-contact phenomenon from an energy perspective is discussed thoroughly in Saito et al [21]. The displacement in which contact occurs, Z cont , is indicated in the horizontal axis of figure 5. After the fiber is already in contact with the object ( d = 0), the base can still be displaced further, i.e. Z can be increased. This means that at this phase the electrostatic force will remain constant at its maximum value, while the elastic force will keep changing until it becomes repulsive when f k > 0. Detachment occurs when f k during the release phase is larger than the maximum attractive force, or f k > f k max . Z det in the horizontal axis of figure 5 indicates the displacement when detachment occurs. When utilizing a fiber with compliance, it can be understood that the maximum attractive force is obtained in the release phase, rather than in the approach phase. The next step in this study is the analysis of an arranged fibers ESC device and its behavior with respect to a rough surface modeled after a sinusoidal curve. Considering an arranged fibers ESC device consisting of eight fibers, we may observe that the attractive force generation becomes more complicated. As opposed to the single fiber model with a flat-surfaced object in which full contact of the spring unit occurs, in the arranged fibers model with an aggregation of spring units, each fiber generates a different attractive force because each has a different d due to the rough surface. In other words, some fibers make full contact while others do not. We could, however, mathematically estimate the total attractive force of the whole ESC device by summing up the attractive force in the individual spring unit. The following equation expresses f device , the force of an arranged fibers ESC ...
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... expression for the electrostatic force is obtained by deriving the equation for a model of a capacitor with two different dielectric substrates in series. The force is positive in the upward direction from the object’s surface. Given the mechanical model of the fiber, we are able to construct a force curve mathematically as shown in figure 5. The force curve signifies the relationship between f att with respect to the displacement of the device base, Z , for a single fiber ESC device when approaching a flat-surfaced object upon applying a voltage. Since the electrostatic force becomes constant once the fiber makes contact with the object, the characteristics of the attractive force are significantly dependent on the elastic force. Therefore, figure 5 shows only the portion with elastic force, from which the behavior of the fiber during the approach and release phases can be analyzed. If a voltage is applied when the fiber tip is far enough away from the object, it will approach the surface because of the electrostatic force. In this phase, there is a point where f k + f e = 0, which keeps the fiber at a stable position. If the fiber is brought closer to the object, the fiber will lose its stable energy point [21], and spontaneously make contact with the object’s surface. The contact occurs when f e > − f k . This jump-to-contact phenomenon from an energy perspective is discussed thoroughly in Saito et al [21]. The displacement in which contact occurs, Z cont , is indicated in the horizontal axis of figure 5. After the fiber is already in contact with the object ( d = 0), the base can still be displaced further, i.e. Z can be increased. This means that at this phase the electrostatic force will remain constant at its maximum value, while the elastic force will keep changing until it becomes repulsive when f k > 0. Detachment occurs when f k during the release phase is larger than the maximum attractive force, or f k > f k max . Z det in the horizontal axis of figure 5 indicates the displacement when detachment occurs. When utilizing a fiber with compliance, it can be understood that the maximum attractive force is obtained in the release phase, rather than in the approach phase. The next step in this study is the analysis of an arranged fibers ESC device and its behavior with respect to a rough surface modeled after a sinusoidal curve. Considering an arranged fibers ESC device consisting of eight fibers, we may observe that the attractive force generation becomes more complicated. As opposed to the single fiber model with a flat-surfaced object in which full contact of the spring unit occurs, in the arranged fibers model with an aggregation of spring units, each fiber generates a different attractive force because each has a different d due to the rough surface. In other words, some fibers make full contact while others do not. We could, however, mathematically estimate the total attractive force of the whole ESC device by summing up the attractive force in the individual spring unit. The following equation expresses f device , the force of an arranged fibers ESC ...
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... expression for the electrostatic force is obtained by deriving the equation for a model of a capacitor with two different dielectric substrates in series. The force is positive in the upward direction from the object’s surface. Given the mechanical model of the fiber, we are able to construct a force curve mathematically as shown in figure 5. The force curve signifies the relationship between f att with respect to the displacement of the device base, Z , for a single fiber ESC device when approaching a flat-surfaced object upon applying a voltage. Since the electrostatic force becomes constant once the fiber makes contact with the object, the characteristics of the attractive force are significantly dependent on the elastic force. Therefore, figure 5 shows only the portion with elastic force, from which the behavior of the fiber during the approach and release phases can be analyzed. If a voltage is applied when the fiber tip is far enough away from the object, it will approach the surface because of the electrostatic force. In this phase, there is a point where f k + f e = 0, which keeps the fiber at a stable position. If the fiber is brought closer to the object, the fiber will lose its stable energy point [21], and spontaneously make contact with the object’s surface. The contact occurs when f e > − f k . This jump-to-contact phenomenon from an energy perspective is discussed thoroughly in Saito et al [21]. The displacement in which contact occurs, Z cont , is indicated in the horizontal axis of figure 5. After the fiber is already in contact with the object ( d = 0), the base can still be displaced further, i.e. Z can be increased. This means that at this phase the electrostatic force will remain constant at its maximum value, while the elastic force will keep changing until it becomes repulsive when f k > 0. Detachment occurs when f k during the release phase is larger than the maximum attractive force, or f k > f k max . Z det in the horizontal axis of figure 5 indicates the displacement when detachment occurs. When utilizing a fiber with compliance, it can be understood that the maximum attractive force is obtained in the release phase, rather than in the approach phase. The next step in this study is the analysis of an arranged fibers ESC device and its behavior with respect to a rough surface modeled after a sinusoidal curve. Considering an arranged fibers ESC device consisting of eight fibers, we may observe that the attractive force generation becomes more complicated. As opposed to the single fiber model with a flat-surfaced object in which full contact of the spring unit occurs, in the arranged fibers model with an aggregation of spring units, each fiber generates a different attractive force because each has a different d due to the rough surface. In other words, some fibers make full contact while others do not. We could, however, mathematically estimate the total attractive force of the whole ESC device by summing up the attractive force in the individual spring unit. The following equation expresses f device , the force of an arranged fibers ESC ...
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... expression for the electrostatic force is obtained by deriving the equation for a model of a capacitor with two different dielectric substrates in series. The force is positive in the upward direction from the object’s surface. Given the mechanical model of the fiber, we are able to construct a force curve mathematically as shown in figure 5. The force curve signifies the relationship between f att with respect to the displacement of the device base, Z , for a single fiber ESC device when approaching a flat-surfaced object upon applying a voltage. Since the electrostatic force becomes constant once the fiber makes contact with the object, the characteristics of the attractive force are significantly dependent on the elastic force. Therefore, figure 5 shows only the portion with elastic force, from which the behavior of the fiber during the approach and release phases can be analyzed. If a voltage is applied when the fiber tip is far enough away from the object, it will approach the surface because of the electrostatic force. In this phase, there is a point where f k + f e = 0, which keeps the fiber at a stable position. If the fiber is brought closer to the object, the fiber will lose its stable energy point [21], and spontaneously make contact with the object’s surface. The contact occurs when f e > − f k . This jump-to-contact phenomenon from an energy perspective is discussed thoroughly in Saito et al [21]. The displacement in which contact occurs, Z cont , is indicated in the horizontal axis of figure 5. After the fiber is already in contact with the object ( d = 0), the base can still be displaced further, i.e. Z can be increased. This means that at this phase the electrostatic force will remain constant at its maximum value, while the elastic force will keep changing until it becomes repulsive when f k > 0. Detachment occurs when f k during the release phase is larger than the maximum attractive force, or f k > f k max . Z det in the horizontal axis of figure 5 indicates the displacement when detachment occurs. When utilizing a fiber with compliance, it can be understood that the maximum attractive force is obtained in the release phase, rather than in the approach phase. The next step in this study is the analysis of an arranged fibers ESC device and its behavior with respect to a rough surface modeled after a sinusoidal curve. Considering an arranged fibers ESC device consisting of eight fibers, we may observe that the attractive force generation becomes more complicated. As opposed to the single fiber model with a flat-surfaced object in which full contact of the spring unit occurs, in the arranged fibers model with an aggregation of spring units, each fiber generates a different attractive force because each has a different d due to the rough surface. In other words, some fibers make full contact while others do not. We could, however, mathematically estimate the total attractive force of the whole ESC device by summing up the attractive force in the individual spring unit. The following equation expresses f device , the force of an arranged fibers ESC ...
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... two kinds of fiber ESC device prototypes were developed: one was a prototype with only one fiber and the other one was with ten fibers arranged at an angle of 45 ◦ , with a 1 mm gap in between each fiber (see figure 7(b)). Figure 8 shows a schematic of the fabrication process for the ESC device prototype. The applied voltage was 600 V. The attractive force was measured by an analytical balance on which the object sample was placed and the prototype was moved to approach the object sample. Figure 7(c) shows a schematic of the experimental setup whereas figure 7(d) depicts an image of the fibers’ tips before and after making contact with a neutrally-charged sample object of 200 μ m amplitude. The force exerted by the prototype with respect to the object was then observed. The experiments were conducted in atmospheric pressure and at room temperature with a relative humidity of 23%. The experimental pressure curve for the single fiber ESC device prototype is given in figure 9(a). Through the experiments, with the aid of a video camera, it was observed that upon applying a voltage, when the fiber was within a certain distance, it spontaneously jumped into contact with the object. Additionally, it was also observed that during the release phase, the fiber maintained contact with the object before detachment, which resulted in the largest attractive pressure in the cycle. These two physically-observed phenomena are consistent with the behavior of the theoretical force curve as shown in figure 5 and are as was discussed by Saito et al [21]. The maximum attractive pressure obtained was − 852 Pa during the approach phase and − 968 Pa during the release phase. Similarly, the experimental pressure curve during the release phase for the arranged fibers ESC device prototype was also obtained as shown in figure 9(b). The applied voltage was 600 V and the sinusoidal surface with 100 μ m wave amplitude was employed as the surface sample. In this experiment, a maximum attractive pressure of − 813 Pa was obtained. Comparing to figure 6, a similar phenomenon of ripples which correspond to the detachment of fiber(s) during the release phase could be observed. Furthermore, in order to understand the effect of a fiber’s spring constant in handling rough surfaces, a graph of maximum attractive pressure with respect to surface wave amplitude for different spring constants is presented in figure 9(c). In the graph, the experimental maximum attractive pressures for surface samples of various amplitudes are plotted as circles along with the theoretical curves for the different fiber’s spring constants of k = 0 . 1 N m − 1 , k = 0 . 4 N m − 1 , and larger values of k (no compliance). The value for k of 0 . 4 N m − 1 is of specific interest because it is the same value as the spring constant for the fibers used in this experiment. An important point from figure 9(c) is that the more compliant the fibers, i.e. the smaller the stiffness value, k , the more they are able to adapt to rougher surfaces. The smaller the stiffness value, the more linear the curve becomes without a significant drop in maximum attractive pressure when handling large wave amplitudes. In contrast, a significant drop in maximum attractive pressure is visible for fibers with no compliance, i.e. the pressure drops by about 70% when handling a surface of 100 μ m wave amplitude as compared to the handling of a flat surface. The four measured pressure values correspond to the four different amplitudes of the surface sample fabricated for this study, i.e. 200, 100, 50, and 0 μ m (flat surface). The variations in experimental data were observed to be relatively small and they can be deemed insignificant as far as the maximum attractive pressure is concerned. The range is between 2–4% for surface samples with 0 and 50 μ m amplitude and 6–7% for those with 100 and 200 μ m amplitude. Along with the increase in the sample’s surface amplitude, the attractive pressure decreases, but for those with an amplitude of 50, 100, and 200 μ m, attractive pressures larger than the ones theoretically predicted with non-compliant fibers were observed experimentally. It can be argued that the fiber’s compliance contributes to the performance improvement of the attractive pressure toward a rough surface. Measured attractive pressures for k = 0 . 4 are found to match the theoretical values and are thought to be generally consistent with theory. To assess the capacitor’s fringe effect, a simple finite element simulation for capacitance calculations has been conducted. The simulated value shows a significantly small variation to the theoretical value. The simulation result, in addition to the experimental results which are generally well-matched with the theory, strongly infer that the capacitor’s fringe effect, though important to consider, is of no significant influence in this ESC device prototype. The fringe effect, however, shall be considered more thoroughly in our future work which involves more fibers for a fully-fledged operation. An important observation is also made when the surface amplitude is 0; the measured attractive pressure was only around 65% of the theoretical value. This finding may be the result of irregularities of the fibers’ tips as depicted in figure 10(a). Fiber tips which are longer than the rest exert a repelling pressure during contact with the surface, by which the attractive pressure decreases. In our prototype, a difference of about 50–100 μ m in fiber tip lengths for the device prototype were measured. These length irregularities came about from the fabrication process, which shall be improved in future work. This occurrence brings up a practical implication: 50–100 μ m irregularities in fiber tip lengths for handling a flat surface are generally comparable to an ideal arranged fibers ESC device prototype handling an object with a sinusoidal surface roughness of 50–100 μ m in amplitude. Of course, the latter results in significantly lower attractive pressure than handling of a flat surface. This is believed to be a possible reason to explain the unmatched theoretical and experimental results. Figure 10(b) illustrates this argument by comparing both models. Though it has been shown in the previous sections that the proposed ESC concept successfully produced an attractive force/pressure compared to what has been theoretically predicted, it is still important to show whether with the force it is able to perform the function of an ESC, ...
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Citations
... By applying opposite voltages to each conductive layer, each beam acts as a bipolar ESC. Since the ESC has a collective beam structure, it can handle soft and fragile objects as demonstrated in R. Dhelika (2013). The deformations of the beams may allow grasping curved-surface soft objects or picking a thin film to be pasted onto a curved surface [15]. ...
... Since the ESC has a collective beam structure, it can handle soft and fragile objects as demonstrated in R. Dhelika (2013). The deformations of the beams may allow grasping curved-surface soft objects or picking a thin film to be pasted onto a curved surface [15]. However, attaching films to curved surfaces requires designated trajectories. ...
... When a voltage is applied, an electrostatic force is generated between the dry adhesive material and the conductive layer, as shown in Figure 11. In a similar study, Dhelika et al. 49 produced compliant electrostatic inductive fibers that are able to conform to the surface irregularity of a substrate. These fibers have a conductive core and an insulator sheath. ...
... The types of material tested for attraction form an essential aspect in the study of electroadhesion. They are characterized by various densities, relative electric permeabilities, and the occurrence of air gaps [4,5]. All these factors have a significant impact on the value of the electroadhesive force and the distribution of the force components on the pad surface. ...
... If a capacitance current flows between the bodies, it will be limited to the actual contact zones, giving rise to an additional resistance, the so-called electrical contact. Materials with a rough structure are attracted with a different force than those with a smooth surface [4,5]. Studies concerned with the relations between the roughness of bodies and electroadhesive attraction confirm that air gaps between the attracted bodies form very important practical study aspects [25]. ...
This paper reports the results of a study concerned with use of electroadhesion for investigation of the attraction force of paper (weight of 50 g/m2). For this purpose, a measuring system was developed and built. Next, a dedicated electroadhesive pad coated with copper and copper mesh on the other side was designed. A new supply control algorithm was also developed and a dedicated charger was built for the purpose of this study. The measurements were carried out with a tensiometer to measure the force with which the electroadhesive pad attracted paper. The research was carried out in a series of several experiments and involved shifting the polarity of the pad and depolarizing the entire system
... This enables the attraction of large sheets of textile materials with the pad and moving them to another place [5]. The materials of rough density are attracted with different force than smooth materials [6,7]. The article [8] explores how materials of different density are attracted. ...
This paper presents a measurement experiment that investigates the effect of using nanocarbon structures coating conducting surfaces energized with high voltage on the conditions for generating high-voltage phenomena. The phenomena studied included current leakage of an insulated plate, ionization phenomena of gases surrounding the plate, optical phenomena accompanying ionization, and detection of gases synthesized under high voltage. The tests were conducted in a gaseous environment with proportions matching the composition of air at normal conditions and at reduced pressure. For comparison, the series of tests was repeated for conductive metallic wafers without the addition of nanostructures. The aim of the study was to analyze the application of nanocarbon structures for the construction of more efficient electroadhesive pads with lower power losses related to current leakage, electroadhesive pads with higher generated electrostatic force and a wider range of applicability for the attraction of different materials. The application of the nanocarbon structure on the electroadhesive pad resulted in the generation of corona discharges in the form of electric arcs and a violet-pink glow.
... To date, our research group has been challenging the Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. development of probe-like compliant electrostatic grippers, such as studies on monopolar polymeric fibers with a conductive part at the core [17], and bipolar micro-pillar gripper [18,19]. The studies show that a prototype consisting of bundled fibers is able to exert a force to conductive objects with rough surfaces, and the compliance of the structure plays an important role in the conforming ability of the gripper to rough surfaces. ...
A 3D-printed-layered structure for forming the compliant bipolar electrostatic gripper is proposed. A prototype gripper module, which consists of an array of elastically deformable bipolar micro-probes, is fabricated using a conventional 3D printer. Experiments are conducted to examine the attractive force and the pick-and-place performance of the prototype. Experimental results show that the prototype module can generate the maximum attractive pressure of 87.1 Pa, which can pick and hold a piece of xerographic paper of 31.2 mg successfully. The effects of residual charges and the probe-tips flattening process on the attractive force are also discussed.
... However, the conventional electrostatic chuck (ESC) has been typically applied only to hold a target with flat surfaces, e.g. a silicon wafer in semiconductor industries, because the attractive force is reduced for rough surfaces [14,15]. Consequently, the contact area needed to generate sufficient electrostatic adhesional force cannot be obtained with the ...
... Van der Waals force, acted as an adhesional force. Therefore, it is obvious that the overall maximum adhesional force will be generated in the release process [14,16,19]. However, the interval of displacement (1 µm) is too large to measure the real maximum adhesional force, which was generated between the interval of 0 to 1 µm. ...
In this paper, we propose a successful fabrication method for a bipolar electrostatic chuck (ESC) device with a beam-array assembly, in order to achieve a fairly flat surface on the beam's tip. A fabricated bipolar ESC device is expected to clamp a curved dielectric object due to its elastically-deformable beams, which are compliant with an object's surface. As a fabrication process, the lithography technique including multiple etching processes against a single etching mask was performed to etch a three-layer material (conductor-dielectric-conductor). Due to the fairly flat surface of the beam's tip (figure 4(c)), sufficient adhesional contact area with the target object for a large adhesional force can be obtained. In order to understand the adhesion performance of the device, an experimental force curve was measured and partially compared with the theoretical adhesional force calculated using finite element analysis. The Pascal-expression for future work dealing with a large surface area was also calculated, corresponding to stacked prototype modules.
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... The electroadhesive forces vary significantly on the same substrate with different surface textures [11]. Hybrid adhesion mechanisms (a combination of electroadhesion and dry adhesion) [17], fluid dielectrics attaching to the pad [18], a layer of elastic foam attaching to the pad [18], and inductive fibers [19] have been investigated to enable the electroadhesive pads to conform to different surface conditions. Flexible electroadhesive pads are able to conform to curved surfaces to some extent if compliant dielectric materials are used [15]. ...
An autonomous, adaptive and intelligent electroadhesive material handling system has been presented in this paper. The system has been proposed and defined based on the identification of a system need through a comprehensive literature review and laboratory based experimental tests. The proof of the proposed concept has been implemented by a low-cost and novel electroadhesive pad design and manufacture process, and a mechatronic and reconfigurable platform, where force, humidity, and capacitive sensors have been employed. This provides a solution to an autonomous elelctroadhesive material handling system that is environmentally and substrate material adaptive. The results have shown that the minimum voltage can be applied to robustly grasp different materials under different environment conditions. The proposed system is particularly useful for pick-and-place applications where various types of materials and changing environments exist such as robotic material handling applications in the textile and waste recycling industry.
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A novel investigation into the relationship between the obtainable interfacial electroadhesive forces and different surface textures is presented in this paper. Different surface textures were generated then characterized based on a recognized areal-based non-contact surface texture measurement platform and procedure. An advanced electroadhesive force measurement platform and procedure were then implemented to measure the obtainable electroadhesive forces on those different surface textures. The results show that the obtained interfacial electroadhesive forces increase with decreasing Sq (root mean square height) value of the substrate surface provided that the difference in Sq between the different substrates is over 5 μm. Also, the higher the applied voltage, the larger the relative increase in electroadhesive forces observed. However, when the difference of Sq value between different substrate surfaces is below 2 μm, the obtained interfacial electroadhesive forces do not necessarily increase with decreasing Sq. Furthermore, the obtainable electroadhesive forces are not necessarily the same when the Sq value of two substrate surfaces are the same due to the fact that the direction of the surface texture plays an important role in achieving electroadhesive forces.
... Electroadhesion is a technique available for developing attachment forces, which is similar to popular methods, such as vacuum suction and magnetic adhesion [1]. Electrostatic force is employed in various applications, such as fabric handling [2][3][4], electrostatic chuck (ESC) handling of silicon wafers [5,6], handling rough objects [7,8], levitation and transportation of silicon wafers [9] and electrostatic glass actuators [10]. Apart from this, electroadhesion is used in a complementary manner as reported in the literature, such as assisted wafer bonding [11], tuning the mechanical behavior of structural elements [12] and tuning the frictional damping behavior of structures [13]. ...
... where µ s is the coefficient of static friction between the actuator and test surface. Now, Equations (8) and (9) can be expressed as: ...
This paper investigates the effect of driving voltage on the attachment force of an electroadhesion actuator, as the existing literature on the saturation of the adhesive force at a higher electric field is incomplete. A new type of electroadhesion actuator using normally available materials, such as aluminum foil, PVC tape and a silicone rubber sheet used for keyboard protection, has been developed with a simple layered structure that is capable of developing adhesive force consistently. The developed actuator is subjected to the experiment for the evaluation of various test surfaces; aluminum, brick, ceramic, concrete and glass. The driving high voltage is varied in steps to determine the characteristics of the output holding force. Results show a quadratic relation between F (adhesion force) and V (driving voltage) within the 2 kV range. After this range, the F-V responses consistently show a saturation trend at high electric fields. Next, the concept of the leakage current that can occur in the dielectric material and the corona discharge through air has been introduced. Results show that the voltage level, which corresponds to the beginning of the supply current, matches well with the beginning of the force saturation. With the confirmation of this hypothesis, a working model for electroadhesion actuation is proposed. Based on the experimental results, it is proposed that such a kind of actuator can be driven within a range of optimum high voltage to remain electrically efficient. This practice is recommended for the future design, development and characterization of electroadhesion actuators for robotic applications.
