WO2025108870A1 - Universal navigation device - Google Patents

Abstract

The present description relates to a navigation guide for a fluid circuit comprising a substrate (10) covered by portions (PN) of active blocks, each portion (PN) of active blocks comprising at least one active block (11), each active block (11) comprising at least one organic electroactive layer (103) disposed between a first electrode (101) and a second electrode (102).

Description

DESCRIPTION

TITLE: Universal Navigation Device

This application is based on, and claims priority from, French patent application number FR 23/12867 filed on November 22, 2023, entitled “Universal navigation device”, which is considered an integral part of this description to the extent permitted by law.

Technical field

[0001] The present description relates generally to devices for navigation in a fluid, for example devices for arterial navigation (endovascular surgery), or for navigation in branched systems such as plumbing conduits or air conditioning circuits.

Prior art

[0002] In endovascular surgery, in order to reach a target blood vessel (such as an artery for example), surgeons use guides to navigate the arterial circuit.

[0003] A guide connects the target artery with the outside: it allows, for example, the delivery of a balloon catheter and a stent in the case of stenosis.

[0004] However, since they are not steerable, they must be introduced using preformed selective angiography catheters. The catheters are chosen according to the shape of the artery: curved, S-shaped, etc. For illustration purposes, the catheters may be catheters referenced under the names 'Head Hunter 1', 'Cobra 1', 'Simmons Sidewinder 2', 'Vertebral', 'Berenstein', 'Multipurpose A'. There is no universal navigation guide that one catheter fits one shape.

[0005] In order to overcome this drawback, devices comprising an electroactive polymer-based actuator have been modeled. For example, in the article by Q. Jacquemin et al. (“Design of a new electroactive polymer based continuum actuator for endoscopic surgical robots” 2020, IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS)), the active block of the actuator is positioned on a 25pm thick PEN substrate. The electrodes are made of PEDOT:PSS and the 6pm electroactive polymer layer is made of P (VDF-TrFE-CTFE). By applying voltages greater than 50V/pm, it is possible to bend the device. The length of the device is 5 cm and its width is 4 mm.

[0006] Thus, it would be possible to manufacture a navigation guide comprising a substrate covered by an active block. When a voltage is applied to the active block, the latter mechanically deforms and causes the substrate to bend.

[0007] However, such devices are still too bulky for arterial navigation. In addition, the device can be either straight or curved in one direction, which is not favorable for navigation in an element in channels with complex geometry (including passages where the device must be oriented in one direction and then the other).

Summary of the invention

[0008] There is a need for a device that is steerable in multiple directions, the device needing to be miniaturizable to be able to navigate blood vessels.

[0009] This aim is achieved by a Navigation Guide for a fluid circuit comprising a substrate covered by portions of active blocks, each portion of active block comprising at least one active block, each active block comprising at least one organic electroactive layer arranged between a first electrode and a second electrode.

[0010] Advantageously, the guide comprises between 2 and 5 portions of active blocks.

[0011] According to a first advantageous embodiment variant, the active blocks are arranged on the same side of the substrate.

[0012] According to a second advantageous embodiment, each portion of active blocks comprises two active blocks arranged on either side of the substrate.

[0013] Advantageously, the active blocks comprise between 1 and 10 organic electroactive layers.

[0014] Advantageously, each active block has a length of between 0.5 and 3 cm, preferably between 1.5 and 2.5 cm.

[0015] Advantageously, each organic electroactive layer has a thickness of between 3 and 15 μm, preferably between 3 and 5 μm.

[0016] Advantageously, each organic electroactive layer (103) is made of PVDF, or one of its copolymers, such as P(VDF-TrFE).

[0017] Advantageously, the first electrode and the second electrode are made of an electrically conductive polymer, preferably PEDOT-PSS.

[0018] Advantageously, the active block portions are covered by an encapsulation layer made of a polymer material, for example, PDMS, PMMA, PVDF or one of its derivatives.

Brief description of the drawings [0019] These characteristics and advantages, as well as others, will be explained in detail in the following description of particular embodiments given without limitation in relation to the attached figures among which:

[0020] Figure 1 shows, schematically and in front view, a navigation guide according to a particular embodiment of the invention - the different parts are not to scale;

[0021] Figure 2 represents, schematically and in three dimensions, the distal part of a navigation guide according to a particular embodiment of the invention;

[0022] Figure 3 shows, schematically and in section, the distal part of a navigation guide according to another particular embodiment of the invention;

[0023] Figure 4 shows, schematically and in section, the distal part of a navigation guide according to another particular embodiment of the invention;

[0024] Figure 5A, Figure 5B, Figure 5C and Figure 5D represent, schematically and in section, different geometries that can be obtained with a distal part of a navigation guide according to different particular embodiments of the invention;

[0025] Figure 6 shows, schematically and in section, a distal part of a navigation guide according to another particular embodiment of the invention;

[0026] Figure 7A and Figure 7B represent, schematically and in three dimensions, electrical wires in a sheath, according to different particular embodiments of the invention;

[0027] Figure 8A and Figure 8B represent, schematically and in top view, electrical tracks on the body of a navigation guide, according to different particular embodiments of the invention;

[0028] Figure 9A and Figure 9B schematically represent electrical tracks, respectively, on one of the faces of the body of the navigation guide and on the other face of the body of the navigation guide, according to another particular embodiment of the invention;

[0029] Figure 10 is a photographic image of a distal portion connected by means of electrical wires, according to another particular embodiment of the invention; and

[0030] Figure 11 is a photographic image of a distal part connected by means of electrical tracks, according to another particular embodiment of the invention.

Description of the embodiments

[0031] The same elements have been designated by the same references in the different figures. In particular, the structural and/or functional elements common to the different embodiments may have the same references and may have identical structural, dimensional and material properties.

[0032] For the sake of clarity, only the steps and elements useful for understanding the embodiments described have been represented and are detailed.

[0033] Unless otherwise specified, when reference is made to two elements connected to each other, this means directly connected without intermediate elements other than conductors, and when reference is made to two elements connected (in English "coupled") to each other, this means that these two elements can be connected or be connected by means of one or more other elements.

[0034] In the following description, when referring to absolute position qualifiers, such as the terms "front", "back", "top", "bottom", "left", "right", etc., or relative, such as the terms "above", "below", "upper", "lower", etc., or to orientation qualifiers, such as the terms "horizontal", "vertical", etc., reference is made unless otherwise specified to the orientation of the figures.

[0035] Unless otherwise specified, the expressions "about", "approximately", "substantially", and "of the order of" mean to within 10%, preferably to within 5%.

[0036] Subsequently, we will more particularly describe the devices for arterial navigation, the device can nevertheless be used for any type of navigation in a fluid, for example for navigation in various branched systems (plumbing conduit or air conditioning circuit for example) or even as a remotely controllable switch.

[0037] We will now describe the navigation guide in more detail with reference to the attached figures.

[0038] As shown in Figure 1, the navigation guide comprises three main parts: the distal part 1 (also called the tip), the transition zone 2 (also called the central part or central core) and the proximal part 3 (also called the body).

[0039] The guide allows navigation in the vessels thanks to the distal end 1 which is adjustable to measure.

[0040] As shown in Figures 1, 2, 3, 4, 5A, 5B, 5C, 5D and 6, the distal end 1 comprises a substrate 10 covered by portions of PN active blocks with N an integer greater than or equal to 2.

[0041] Preferably, the guide comprises between 2 and 5 portions of active blocks. By between X and Y, it is meant here and hereinafter that the terminals are included. [0042] Each portion of PN active blocks comprises at least one active block 11. Each active block 11 comprises at least one electroactive layer 103, arranged between a first electrode 101 (also called lower electrode) and a second electrode 102 (also called upper electrode). The electrodes 101, 102 are positioned on either side of the electroactive layer 103.

[0043] When a voltage is applied to an active block 11, the latter is mechanically deformed. The active blocks 11 can be actuated independently of each other.

[0044] Thus, the navigation guide is fundamentally distinguished from the prior art by the presence of several PN portions of active blocks, electrically activatable independently of each other.

[0045] The presence of several PN portions of active blocks makes it possible, by applying a voltage to the active blocks 11, to obtain, not only, several deformation configurations of the distal part 1, but also a finer deformation of the distal part 1. The actuated length is adjustable.

[0046] Thus, by activating one or more portions of active PN blocks, the surgeon can fictitiously vary not only the distal length 1 but also its shape.

[0047] With such a device, it is thus possible to achieve large angles.

[0048] The substrate 10 comprises a first face 10a and a second 10b.

[0049] Each portion PN of active blocks can comprise, independently of each other, one active block 11 or two active blocks 11.

[0050] The active blocks 11 of the different PN portions of active blocks can be positioned on the first face main face 10a and/or on the second main face 10b of the substrate 10.

[0051] Preferably, each portion of active blocks PN comprises an active block 11 arranged, on either side, of the substrate 10. This makes it possible to obtain a navigation guide which is straight in the absence of applied voltage. Indeed, in the case where the active blocks 11 are on only one side, prestresses may exist in the multilayer forming the active block 11 (due to differences in thermal expansion coefficient between the layers and/or to the evaporation of the solvent during the manufacture of the device). These prestresses may cause the distal part 1 to flex in a direction which is not the one desired for the application. The arrangement of active blocks 11 on either side of the substrate

10 (preferably identical active blocks within the same PN portion) leads to the cancellation of bending constraints and the elimination of this pre-deformation.

[0052] The end of the guide 1 is thus orientable in two directions: the bending can be done indifferently in one direction or the other. Even if a PN portion of active block is activatable in both directions, it is possible to connect or activate only one of the two sides depending on the use of the guide.

[0053] Preferably, the active blocks 11 comprise between 1 and 10 electroactive layers 103. When the active block comprises several electroactive layers 103, the active block

11 is formed of a stack comprising an alternation of electroactive layers 103 and first electrodes 101 and second electrodes 102. The stack begins with a first electrode 101 and ends with a second electrode 102. Each active block 11 is formed of a pattern 100 or a repetition of a basic pattern 100 formed of a first electrode 101, an electroactive layer 103 and a second electrode 102.

[0054] Each active block has a length 1a, for example, between 0.5 and 3 cm, preferably between 1.5 and 2.5 cm.

[0055] Each active block 11 has, for example, a width between 0.1 mm and 1 cm, preferably between 0.25 mm and 3 mm. With such widths, it is possible to carry out arterial navigation.

[0056] Each electroactive layer 103 has a thickness ed, for example, between 3 and 15 μm, preferably between 3 and 5 μm. With such thicknesses, the applied voltages can be relatively low.

[0057] The voltage applied to each active block is preferably between 50 V and 1000 V, and preferably between 50 V and 600 V. For a thickness of 4 μm, the applied field is, for example, between 10 MV/m and 250 MV/m and preferably between 10 MV/m and 150 MV/m.

[0058] The electrodes 101, 102 have, for example, a thickness ec of between 0.1 and 3 μm, preferably between 1 and 2.5 μm.

[0059] The distal part 1 comprises two ends: a first end is in contact with the central part 2 and a second end is free. In other words, it is not connected to other elements.

[0060] Preferably, the portion of active blocks closest to the end of the substrate 10 is at a distance 1m of 0 to 2 cm from the second end of the distal part 1 and, even more preferably, at a distance of 0.5 to 1.5 cm from the end of the distal part. This distance 1m is also called dead length. [0061] The distance li between two consecutive portions of active blocks PN-1 and PN is, for example, between 0.1 and 5 mm, preferably between 0.5 and 2 mm.

[0062] The different active blocks 11 may have the same dimensions or different dimensions.

[0063] For example, as shown in FIG. 4, the device comprises three portions of active blocks P1, P2 and P3, each portion of active blocks having an active block 11 arranged on either side of the flexible substrate 10. The first portion of active blocks P1 comprises active blocks 11 having a single electroactive layer 103 (i.e. a single pattern 100), the second portion P2 of active blocks comprises active blocks 11 having 4 electroactive layers (i.e. 4 patterns 100), and the third portion P3 of active blocks comprises active blocks 11 having two layers of active blocks (i.e. 2 patterns 100). The dimensions (length and thickness in particular) of the active blocks 11 are different here.

[0064] Preferably, each electroactive layer 103 is an organic piezoelectric layer.

[0065] Electroactive materials are materials that deform under the application of an electric field. In particular, piezoelectric materials (such as PVDF-TrFE) are electroactive materials. There are other classes of electroactive materials, for example, electrostrictive materials (such as PVDF-TrFE-CTFE).

[0066] Each electroactive layer 103 preferably comprises a polymer matrix made of PVDF, a PVDF copolymer or a PVDF terpolymer. It may be a copolymer of vinylidene fluoride and at least one other monomer copolymerizable with VDF. Advantageously, the copolymer comprises at least 50 mol%, preferably at least less than 70% by weight, even more preferably at least 80% by mole of VDF.

[0067] By way of illustration, the copolymerizable monomer(s) are, for example, chosen from chlorotrifluoroethylene (CTFE), chlorofluoroethylene (CFE), hexafluoropropylene (HFP), trifluoroethylene (VF ₃ ), methyl methacrylate (MMA), tetrafluoroethylene (TFE), and perfluoro(alkyl vinyl) ethers such as perfluoro(methyl vinyl) ether (PMVE).

[0068] For example, the copolymer is a copolymer of poly(vinylidene fluoride-trifluoroethylene) PVDF / TrFe, also noted P(VDF-TrFe) or PVDF-CTFE.

[0069] It can also be a terpolymer. For example, a PVDF/TRFE/CTFE or PVDF/TRFE/CFE terpolymer will be chosen. Such materials are so-called electrostrictive materials.

[0070] According to another embodiment variant, the polymer is not a ferroelectric polymer: it may be PVDF-HFP.

[0071] Each organic electroactive layer 103 may be a composite material. For example, the layer may comprise, in addition to the polymer matrix, ferroelectric particles and, optionally, PEDOT:PSS particles in order to increase the relative permittivity of the material and thus improve its electrical behavior.

[0072] For example, the ferroelectric particles are made of BaTiO3 (BTO), PZT (lead zirconate titanoate), AIN, ZnO, or even SBN (Sr-Ba-Nb oxide) or SBT (Sr-Ba-Ti oxide). Such particles are for example used with a crosslinkable epoxy-type matrix. Thus, the layer has a certain stiffness, which makes it possible to efficiently transform the electrical impulse into mechanical displacement. [0073] Preferably, the electrodes 101, 102 are made of an electrically conductive polymer, preferably PEDOT-PSS (poly(3,4-ethylenedioxythiophene).

[0074] The materials forming the different active blocks 11 may be identical or different. Preferably, they are identical. Even more preferably, each active block 11 comprises PEDOT-PSS electrodes and an electroactive layer of P(VDF-TrFe).

[0075] When using the navigation guide, depending on the desired shape, it is possible to not apply any voltage, or to apply one or more different voltages to the active blocks 11. With such a device, it is possible to have one end curved in one direction or the other, a straight end or an S-shaped end (Figures 5A to 5D).

[0076] The substrate 10 is a flexible substrate, that is to say that it can deform reversibly.

[0077] The substrate 10 may be made of polyimide (PI) or poly(ethylene naphthalate) (PEN). It may also be made of polyarylate (PAR).

[0078] The thickness (denoted es) of the substrate 10 is, for example, between 25 pm and 125 pm, preferably between 25 pm and 75 pm.

[0079] Each of parts 1, 2 and 3 of the navigation guide may comprise a substrate for supporting different elements (electrical tracks, electrical wires, active blocks). Alternatively, part 3 (body) may be formed from braided or concentric wires, preferably sheathed.

[0080] When the proximal portion 3 and the transition zone 2 each comprise a substrate, the substrate of the proximal portion 3 and the substrate of the transition zone 2 may be identical or different. These substrates are, preferably, made of polymer such as polyimide (PI), poly(ethylene naphthalate) (PEN) or polyarylate (PAR). These substrates can also be metallized (by adding a layer of metal) such as zinc or titanium. The thickness of these substrates is, for example, between 25 pm and 250 pm.

[0081] The substrate 10 of the distal part 1 is thinner than those of the central 2 and proximal 3 parts in order to be able to be deformed more easily. According to another embodiment variant, the substrate 10 of the distal part 1 may have the same thickness as those of the central 2 and proximal 3 parts.

[0082] Electrical connection means 5, 7 are arranged so as to convey the electrical signal to the active blocks 11 positioned at the distal part 1.

[0083] The connection of the electrodes 101, 102 to each other can be shared in order to divide the number of electrical tracks 5 / electrical wires 7 (figure 6). This makes it possible to reduce the size due to the connections, and thus reduce the width of the substrate. The device can comprise an encapsulation layer. This encapsulation layer is not shown in figure 6.

[0084] Several solutions can be envisaged for routing the electrical signal from the body 3 to the core 2 then to the distal part 1 of the navigation guide.

[0085] According to a first variant embodiment, for example shown in FIGS. 7A and 7B, the connection is made by means of electrical wires 7 (i.e. electrically conductive wires). The wires 7 are in an electrically insulating sheath 8. The wires 7 can be braided (FIG. 7A) or positioned concentrically (FIG. 7B). [0086] According to another alternative embodiment, for example shown in FIGS. 8A, 8B, 9A and 9B, the connection is made by means of electrical tracks 5 (i.e. electrically conductive tracks). The tracks 5 can be printed on the substrate 4. The tracks can be arranged on a single face of the substrate (FIGS. 8A and 8B) or on both faces of the substrate (FIGS. 9A and 9B). When the tracks are on a single face of the substrate 4 and the device comprises active blocks on either side of the substrate 10, vias 6 are used to allow the tracks to be on one and the same side.

[0087] The tracks 5 may be made of a metal (gold or silver for example), or of an electrically conductive polymer material. For example, the electrically conductive polymer material is PEDOT:PSS. It may also be a polymer in which electrically conductive particles are dispersed, for example carbon, carbon or gold particles. The particles advantageously have a larger dimension of less than 300 nm to avoid increasing the roughness.

[0088] Several configurations are possible, in order to connect the electrical tracks 5 and/or the electrical wires 6.

[0089] For example, it is possible to cover a part of the lower electrode 101 (the one in contact with the substrate) with one of the electrical tracks 5.

[0090] The electrical tracks 5 and/or the electrical wires 7 can be connected to the lower electrode 101 of an active block 11 by means of an electrically conductive glue (of the charged epoxy type for example) or by means of soldering.

[0091] Optionally, an electrically conductive plate (for example made of metal, in particular copper) may be positioned on the substrate, on the one hand glued or welded to the lower electrode 101 and, on the other hand, glued or welded to the electric wire 7 or to the electric track 5.

[0092] According to another variant embodiment, mechanical systems such as staples or rivets can be used to connect the electrode 101 of the active block 11 to the wire 7 or to the track 5.

[0093] The various connections may be covered with a cover. In particular, it is possible to use an electrically conductive cover. For example, the cover may comprise nanoparticles. The cover makes it possible to plug any holes and/or to avoid breakdown phenomena.

[0094] It is also possible to increase the stiffness of the central core 2 by locally adding an additional layer on the substrate. For example, it may be a polymer layer. The polymer may be identical or different from the polymer of the substrate. It may also be a metallized polymer layer. The polymer layers may be deposited by bonding. Alternatively, the additional layer is a dielectric layer, for example printed by screen printing. It may also be a metal sheet. The sheet may have a thickness of between 10 and 1000 μm, preferably between 10 and 100 μm. The sheet may be made of zinc or aluminum.

[0095] Preferably, the distal end 1 is covered by an encapsulation layer. The encapsulation layer coats the different portions of active blocks. The encapsulation layer may be made of a polymer material, for example, an epoxy, polydimethylsiloxane (PDMS), poly(methyl methacrylate) (PMMA), polyvinylidene fluoride (PVDF) or one of its derivatives. [0096] Even more preferably, the distal end 1, the central core 2 and at least part of the body 3 are covered by the encapsulation layer.

[0097] Encapsulation may be carried out by thermal evaporation, by dipping or by spraying a solution. The encapsulation step is advantageously carried out once the electrical connections have been made.

[0098] Radiopaque elements may be added to the device, for example, on the flexible substrate or on the encapsulation layer, between the portions of PN active blocks, in order to be able to provide visual tracking of navigation in the target system. The elements are, for example, in the form of crosses, squares or dots.

[0099] The distal part 1 has a length L preferably between 1 and 7 cm, and preferably between 1 and 4 cm.

[0100] The length L corresponds to the sum of the lengths of the different active blocks 11, of the different inter-active block distances li and of the extreme length 1m.

[0101] The navigation guide has a length which can be, for example, up to 180 cm or even 300 cm.

[0102] The distal part 1 can be produced in the following way:

[0103] a) depositing several electrically conductive zones on a substrate 10, the electrically conductive zones forming first electrodes 101,

[0104] b) forming electroactive layers 103 on the electrically conductive areas,

[0105] c) forming second electrodes 102 on the electroactive layers 103. [0106] If necessary, it is possible to repeat steps b) and c) to form a repetition of patterns 100 (first electrode 101, electroactive layer 103, second electrode 102).

[0107] During step b), the electroactive layer 103 can be deposited by spin coating. Other types of localized deposition can be used such as screen printing, spraying, dispensing or even inkjet deposition. Preferably, the electroactive layer is deposited by screen printing. In one pass, the deposited thickness is between 1 and 20 μm. It is possible to superimpose several layers by screen printing until the desired final thickness is reached.

[0108] For the active blocks 11, between 1 and 10 layers will be deposited, preferably at least five layers and, preferably, ten layers of composites intercalated between two electrodes 101, 102, according to the following sequence: N x (electrode 101 / composite 103 / electrode 102). The number of layers deposited depends on the thickness of the dielectric.

[0109] The method also comprises a step of crystallizing the layer of electroactive material 103, to improve its performance. This irradiation is for example implemented with UV flash light, with a flash duration, or pulse, of between approximately 500 μs and 2 ms, a fluence (energy delivered per unit area) of between approximately 15 J/cm ² and 25 J/cm ² , and with light of wavelength of between approximately 200 nm and 380 nm. The number of flashes, or pulses, of UV light produced during this irradiation varies according to the thickness over which the electroactive material must be crystallized. For example, for a thickness of P(VDF-TrFe) equal to approximately 2 μm, the irradiation can be implemented with a fluence equal to approximately 17 J/cm ² , a pulse duration equal to approximately 2 ms and a number of pulses equal to 5.

[0110] The electroactive material, having possibly undergone a previous crystallization, is then subjected to annealing, for example, carried out at approximately 130°C for approximately 60 min, to finalize the total crystallization of the material. The annealing can be carried out at ambient pressure or at low pressure.

[0111] The crystallization of the dielectric material can therefore be carried out in two stages: firstly, irradiation by UV light pulse to properly crystallize the second face of the layer of dielectric material in order to increase its thermal conductivity, then thermal annealing completing the crystallization for the rest of the material not crystallized by the previous irradiation.

[0112] When the dielectric material is a P(VDF-TrFe)-based copolymer, a step of polarizing the material is carried out before its use. This step can be carried out, for example, by applying a direct current voltage to its terminals, via the electrodes. This polarization is carried out only once for the entire lifetime of the material. This polarization by direct current can be carried out at room temperature or hot (up to approximately 100°C). When the polarization is carried out at room temperature, it is possible to apply a direct voltage up to approximately 150V/pm or even 200V/pm of layer thickness for a duration, for example, of between a few seconds and a few minutes. For example, a voltage of 120V/pm will be applied for 20s. When the polarization is carried out hot, for example at a temperature of approximately 90°C, a direct voltage for example between approximately 50 V and 80 V per micron can be applied to the dielectric layer for a duration for example between approximately 1 min and 5 min. The temperature is then lowered until it reaches room temperature, then the electric field applied to the material, via the applied DC voltage, is stopped. Such polarizations allow PVDF to reach remanent polarization values of 8pC/cm ² .

[0113] The dipoles inside the layer remain oriented in this way, even when the material is no longer subjected to this electric field. The material can be polarized in this way by applying an initial polarization voltage to the terminals of the electrodes. A material thickness of between 3 and 4 gm per layer will preferably be chosen in order to promote the polarization of the material of this capacity, and the level of the electric voltage applied between the electrodes to achieve the initial polarization of the material (when the material must be initially polarized).

[0114] Annealing is advantageously carried out at the end of the process, or between the different stages. The annealing is, for example, at a temperature between 100°C and 150°C, preferably around 100°C to remove residual traces of solvent and/or finalize the crystallization of the material.

[0115] Annealing can be carried out under vacuum. For example, it is a vacuum of the order of 1 mbar. The duration of annealing, for 1 mbar, can be at least 1 minute, preferably 3 minutes.

[0116] At the end of the method, contact is advantageously made so as to connect the active blocks 11 of the distal part 1 to the central core 2 and to the proximal part 3 of the navigation guide.

[0117] Various embodiments and variations have been described. Those skilled in the art will understand that certain features of these various embodiments and variants could be combined, and other variants will occur to those skilled in the art.

[0118] Finally, the practical implementation of the embodiments and variants described is within the reach of those skilled in the art from the functional indications given above.

[0119] Illustrative and non-limiting examples of different embodiments

[0120] In these examples, the substrate is made of polyimide. It is locally covered by portions of active blocks. The active blocks comprise ten piezoelectric layers in PVDF-TrFE; the electrodes are made of PEDOT:PSS.

[0121] In a first example, the device is connected by wires (figure 10). The wires are sheathed. They are braided.

[0122] In a second example, the device is connected by tracks (figure 11). The tracks are silver.

[0123] The devices are operational and the distal part can take several forms.

Claims

1. Navigation guide for a fluid circuit comprising a substrate (10) covered by portions (PN) of active blocks, each portion of active blocks (PN) comprising two active blocks (11), each active block (11) being arranged on either side of the substrate (10), each active block (11) comprising at least one organic electroactive layer (103) arranged between a first electrode (101) and a second electrode (102), the active blocks (11) being actuable independently of each other. 2. Navigation guide according to claim 1, characterized in that the guide comprises between 2 and 5 portions of active blocks (PN). 3. Navigation guide according to any one of the preceding claims, characterized in that the active blocks (11) comprise between 1 and 10 organic electroactive layers (103). 4. Navigation guide according to any one of the preceding claims, characterized in that each active block (11) has a length of between 0.5 and 3 cm, preferably between 1.5 and 2.5 cm. 5. Navigation guide according to any one of the preceding claims, characterized in that each organic electroactive layer (103) has a thickness of between 3 and 15 pm, preferably between 3 and 5 pm. 6. Navigation guide according to any one of the preceding claims, characterized in that each organic electroactive layer (103) is made of PVDF, or one of its copolymers, such as P(VDF-TrFE). 7. Navigation guide according to any one of the preceding claims, characterized in that the first electrode (101) and the second electrode (102) are made of an electrically conductive polymer, preferably PEDOT-PSS. 8. Navigation guide according to any one of the preceding claims, characterized in that the portions of active blocks (PN) are covered by an encapsulation layer of a polymer material, for example, PDMS, PMMA, PVDF or one of its derivatives.