Method for detecting environmental changes in a cable

Abstract

A method for detecting an environmental change in the vicinity of at least one electrically conductive portion of a lift, tow or boundary cable, said environmental change being associated with the relative movement of at least one person, animal or object with respect to said portion, said method comprising the step of detecting a change in the capacitance of said portion indicative of said movement.

Description

Technical Field

[0001] The present invention relates to a method for detecting environmental changes in relation to the proximity of a person, animal, or object to a traction, lifting, or boundary cable, and to an apparatus for performing the method. Background Technology

[0002] Cable-driven parallel robots hold great promise in industry. These robots are capable of lifting and manipulating loads or tools that can be very heavy and / or bulky. They consist of parallel mechanisms consisting of at least two cables connected to a base and to a basket or effector. The lifting or traction cables of cable-driven parallel robots can reach lengths of more than ten meters. Obstacles, especially people approaching one of these traction or lifting cables, represent a real danger. Ensuring safety around these robots is essential.

[0003] In industrial applications, entry into a robot's work area is prohibited to prevent any collisions or accidents between humans and robots. Current cable-driven parallel robots occupy a significant area, resulting in a loss of usable space. Furthermore, any intervention in the robot's operating area while it is in motion will force a stop and thus slow down its operation.

[0004] Similar issues may arise with other lifting structures that include cables (such as cranes). Safety is ensured through safety regulations and training. Therefore, human parameters are crucial, and negligence can lead to serious consequences.

[0005] Furthermore, the structure of these cables makes them difficult to inspect using visual methods. In fact, the cables are very long and have a relatively small diameter compared to their length, making image analysis-based inspection relatively ineffective.

[0006] Another useful feature is its ability to secure areas defined by cables (e.g., retractable safety barriers) to prevent any intrusion into those areas. Summary of the Invention

[0007] Invention Statement

[0008] Therefore, there is a need for a method that is easy to use in various systems and can ensure the safety of areas near the lifting or traction cables of cable-driven parallel robots or other types of lifting or traction machines (e.g., cranes) to prevent any collisions. Additionally, it has the benefit of detecting the risk of intrusion into areas defined by at least one cable. Invention Overview

[0010] The object of the present invention is to satisfy some or all of these needs, and in one aspect of the invention, this object is achieved by a method for detecting environmental changes near at least one conductive portion of a lifting, traction, or boundary cable, the environmental changes being related to the relative movement of at least one person, animal, or object relative to said portion, the method comprising the step of detecting a change in capacitance of said portion representing said movement.

[0011] Specifically, the cable may be a lifting or traction cable for a cable-driven parallel robot or other type of lifting or traction machine (e.g., a crane), and the environmental changes are related to the proximity of the person, animal, or object to the part, thereby creating a risk of collision between the person, animal, or object and the part and thus constituting a potential obstacle.

[0012] The present invention can automatically detect the presence of obstacles near the cable by monitoring the capacitance changes of the cable portion.

[0013] The advantage of this invention is that it can ignore external interference, especially external interference related to relative humidity, without the need for periodic calibration, thereby improving the reliability of the detection.

[0014] The conductive cable section is at a predetermined variable potential and emits a radial electric field around it. Intrusion causes a change in this electric field, and the change in the self-capacitance of the conductive cable section reflects this change in electric field.

[0015] Advantageously, capacitance can be represented by a voltage proportional to capacitance: V = K x C. Analyzing changes in this voltage electronically can detect the presence of obstacles near conductive cable sections, and even identify and / or determine the distance to obstacles.

[0016] One advantage of the method according to the invention is the ability to safely develop areas where cables are moving without physically prohibiting individuals from approaching those areas. Such areas include, for example, the operating area of ​​a cable-driven parallel robot or an area near a crane.

[0017] If the cable is a boundary cable, environmental changes are associated with the proximity of individuals, animals, or objects to the area, thus creating a risk of intrusion. Therefore, this invention enables the security of an area defined by at least one cable, which may be particularly long and difficult to monitor. The cable may define the area, for example, by surrounding the area or being present at a passageway providing access to it.

[0018] Protective barrier

[0019] According to one embodiment, the cable extends at least partially around a guiding, driving, and / or winding system. This guiding, driving, and / or winding system may include at least one pulley and / or at least one winder and / or at least one support structure, such as a boom crane.

[0020] The guiding, winding, and / or driving system may be subject to electrical influences from the mechanical components constituting the system. These electrical influences create capacitive coupling that can easily interfere with the capacitive detection of the movement. A barrier at the cable's potential may extend at least partially around one or more of these mechanical components, particularly at least partially around the cable guiding, driving, and / or winding system.

[0021] Therefore, advantageously, the cable extends over at least a portion of its length facing the barrier, which is raised to the predetermined potential, in particular by a voltage follower.

[0022] This barrier, raising the potential to the cable, can reduce or even eliminate capacitive coupling between the cable and the components constituting the guiding, driving, and / or winding system. Without this barrier, capacitive coupling is much higher than the cable's self-capacitance. A disadvantage of the absence of a barrier is that the ratio C... obstacle / C cable It is much smaller than when a barrier is present, thus reducing the sensitivity of capacitance detection.

[0023] For a given cable length l', the capacitance of that cable portion facing the barrier raised to a predetermined potential is advantageously always the same, preferably zero.

[0024] The barrier can also be at least partially surrounded by a grounded shield. The portion of the cable facing the barrier and shield is then isolated from external electrical influences.

[0025] Guiding, driving, and / or winding systems can be electrically insulated from cables, particularly by being covered with electrically insulating material.

[0026] The cable can be unwound from the winding and / or drive system, and the detection of capacitance changes in the at least one conductive portion can be performed by compensating for load changes caused by modifications to the unwound cable length l. Specifically, the unwound cable length l can be defined at any time by an angle encoder.

[0027] The tangled portion of the cable can be isolated by a barrier and / or grounding shield that raises the cable to a predetermined potential.

[0028] Therefore, in one embodiment of the invention, by obtaining the amount representing the capacitance change of the cable portion and the amount representing the movement of the cable (especially winding or unwinding), it is possible to determine whether the capacitance change is primarily due to the movement of the cable and / or due to the presence of individuals, animals, or objects near the cable that could easily constitute an obstacle.

[0029] Components under traction

[0030] The conductive cable section may be subject to electrical influences from other external components.

[0031] The cable may be attached to a component, for example. This component could be a mounting system and / or load and / or operating tool and / or basket, or any other component that can be attached to the cable. The portion of the cable in contact with this component may then be subject to the electrical influence of that component.

[0032] To limit this effect, the conductive cable portion can extend for a length less than the cable length if necessary; preferably, the distal portion of the cable does not emit an electric field. Therefore, since the element is not fixed to the conductive portion, the electrical effects will not interfere with the movement and capacitance detection.

[0033] Alternatively, the conductive portion extends to the distal end of the cable. In this case, the conductive portion may include the entire cable. The movement detection can then be performed along the entire cable.

[0034] Additionally, the portion can make electrical contact with the conductive portion of an element attached to the cable. Therefore, both the cable and the element are sensitive to field effects and capable of capacitively detecting the approach of a person, animal, or object.

[0035] This is advantageous because an obstacle approaching a component fixed to the cable could cause a collision, and preferably, capacitance detection makes it equally sensitive to the approach of the obstacle.

[0036] Components attached to cables are covered, for example, with conductive paint or conductive rubber to enable them to conduct electricity.

[0037] Additionally, the cable may include at least one conductor supplying power to an element moving via the cable, which may optionally include an effector that can be powered by the cable, for example, via a connector located on the element, particularly on the basket. The power supply conductor may be surrounded at least by a barrier raised to the predetermined potential, with the at least one conductive portion located outside the barrier. Furthermore, a grounding shield may surround the barrier, with the at least one conductive portion located outside the shield.

[0038] Therefore, the cable can supply power to the component in addition to pulling and / or raising it. For example, the component may include a manipulator, such as a painting robot, a rivet gun, or a drill.

[0039] Reference data

[0040] The capacitance can be compared with reference data as it changes over time and / or according to the movement of the cable, thereby detecting the presence of a person, animal, or object, identifying the person, animal, or object, and / or estimating the distance of the person, animal, or object from the cable.

[0041] Reference data may include all values ​​representing the capacitance or capacitance change of a cable, measured or stored for a given situation.

[0042] For example, reference data could include voltage changes measured when a person, animal, or object is located at a distance d from the cable. Detecting a voltage change that is substantially equal to this measured change can provide an alert about the presence of a person, animal, or object at a distance d from the cable.

[0043] The reference data may include a set of voltage changes measured when a person, animal, or object is located at various distances d from the cable. Thus, for example, by comparing with this data, the distance to the person, animal, or object can be estimated.

[0044] The reference data may also include a set of capacitance values ​​measured during cable winding for a given unwinding length *l*, in the absence of a person, animal, or object, or in an operating environment including static obstacles. Detecting a capacitance for a given length that differs from the capacitance included in the reference data may indicate the presence of a person, animal, or object, or a malfunction.

[0045] Reference data can be measured while the cable is on a predetermined trajectory and / or for a given length of cable and / or if there are individuals, animals or objects located at a given distance from the cable.

[0046] Reference data may depend on parameters such as: the length of the cable and / or the distance of a person, animal or object from the cable and / or the presence of static obstacles near the cable and / or the presence of elements fixed to the cable.

[0047] Reference data can be voltage, capacitance, current, or dimensionless data such as voltage ratios. Capacitance changes can be determined by acquiring at least one voltage transmitted by the circuit, particularly by an electronic regulator.

[0048] Reference data can be obtained through experiments, such as in a laboratory.

[0049] Reference data can be obtained through calibration procedures in the cable's operating area.

[0050] Fingerprints of individuals, animals, or objects

[0051] The method according to the invention may include acquiring reference data obtained by performing movement of a person, animal, or object relative to the cable portion in a predetermined manner; this reference data is thus referred to as a "capacitive fingerprint." This acquisition can then obtain the capacitance evolution caused by the relative movement of the person, animal, or object relative to the cable as the distance d between the person, animal, or object and the cable changes. Therefore, for a given set of distances, the effect of the person, animal, or object on the capacitance of the cable is known according to the change in distance between the cable and the person, animal, or object, and this effect is independent of the length of the cable.

[0052] The relative change in capacitance of a cable caused by the proximity of a person, animal, or object, ΔC(d) / C(l,d), can be defined as the "relative sensitivity," which depends on the length of the cable. For example, after unwinding the cable, the greater the capacitance, the lower the relative sensitivity.

[0053] The characteristics of reference data for fingerprints of individuals, animals, or objects vary substantially according to, for example, the height and / or surface area of ​​the individual, animal, or object. It is advantageous to determine upper and / or lower limits of the variations in capacitance and / or voltage to establish reference data.

[0054] Obtaining reference data advantageously allows for the identification of individuals, animals, or objects detected near the cable by comparing them with reference data corresponding to many different individuals, animals, or objects.

[0055] The reference data preferably includes the capacitive fingerprint of a person on a cable. The capacitive fingerprint of a person on a cable can be estimated, for example, by a voltage change that decreases by 1 / d as d increases, where d is the distance between the person and the cable.

[0056] Track signature

[0057] The method according to the invention may also include obtaining reference data by giving the cable and / or the elements attached to the cable a predetermined movement, in particular taking into account the capacitance change caused by the presence of a static environment due to the cable movement, the reference data being referred to as a “capacitance signature”.

[0058] The capacitance change can be determined, thus defining the expected capacitance change for a decrease or increase of l ± Δl in the cable length. This allows estimation of the capacitance change at two points M in the absence of individuals, animals, or objects. i and M i+1 The expected capacitance change between them.

[0059] For example, detection based on this rate of change can in particular avoid interference that is relatively slow to occur, such as changes in the relative humidity of the air.

[0060] Protective measures

[0061] The method according to the invention preferably includes the following steps: upon detecting that a person, animal, or object is near the portion of the cable, performing at least one predetermined action, which is particularly selected from: generating a visual, audible, or tactile alarm; stopping the movement of the cable and / or components moved by the cable; and preventing startup and / or restart.

[0062] The cable's travel speed can be reduced over a certain distance before a potential collision with an obstacle, and / or the cable's trajectory can be modified before a potential collision with an obstacle.

[0063] The present invention is advantageous for detecting the risk of collision between a person and at least some of the cables of a cable-driven parallel robot, or for detecting a person approaching or avoiding boundary cables, for example, when a person is inside a retractable safety barrier.

[0064] In the case of boundary cables, it is preferable to generate an audible alarm to warn individuals that they are approaching or crossing the cable. Alarms can also be sent via communication means to warn of environmental changes related to the detection of individuals, animals, or objects approaching the cable.

[0065] Upon detecting a person, animal, or object, these individuals, animals, or objects can then be identified using optical sensors, particularly image recognition systems. Identifying the person, animal, or object allows for adjustments to actions, especially when focusing on obstacles. Storing data derived from the identification of the person, animal, or object, along with detected capacitance changes, enriches the reference data, for example, by defining the capacitance fingerprint of the person, animal, or object.

[0066] The device according to the invention is advantageously configured to comply with safety standards, such as EN ISO 13849-1 and / or IEC 61508 and / or CEM 2014 / 30 / EU Directive and / or 2014 / 35 / EU Low Voltage Directive, preferably covering at least the low performance class PLA and / or the low safety integrity class SIL1, and more preferably covering the high performance class PLe and / or the high safety integrity class SIL3.

[0067] The device is then advantageously configured to reduce system and / or random failures. Random failures depend particularly on the reliability of the device's components, which is measured, for example, by the component's mean time to failure (MTTF) and failure rate λ. dDefined by and / or service life; the preferred redundancy architecture of the components preferably conforms to the architecture of 1oo2 or categories B to 4 of standards EN ISO 13849-1 and IEC 61508 respectively, and / or CEM 2014 / 30 / EU Directive and / or 2014 / 35 / EU Low Voltage Directive, and / or includes monitoring of the functionality of the components, as well as monitoring of the functionality of the equipment.

[0068] Preferably, monitoring of the equipment's functionality is performed periodically during equipment startup and / or cable operation. The cable preferably includes at least one element capable of monitoring the equipment's operation when the cable is used in lifting, traction, or boundary equipment. Specifically, this at least one element is attached to the cable and adapted for detection by a sensor located at the entrance of the equipment's winding coil and / or near the cable. This element is, for example, a conductive loop surrounding the cable or an RFID tag located on the cable, with an RFID reader present at the entrance of the winding coil. The monitoring element can be configured for detection by an electromechanical detector or an inductive detector. The monitoring element can be a loop (e.g., a metal ring) surrounding the cable or an RFID tag attached to the cable, with the RFID reader located horizontally at the winding coil and / or near the cable.

[0069] Alternative and / or additional grounds may be used to locate the monitoring element inside the cable.

[0070] Alternatively and / or additionally, the monitoring element may be located near one or more cables (on the basket or effector) or inside the moving envelope of one or more cables.

[0071] The device’s monitoring elements are able to verify that there is no drift over time that would lead to doubts about the measured person, animal, object, or obstacle.

[0072] Detection of a fault and / or drift by one of these monitoring elements preferably results in the cessation of cable operation and / or an alarm, such as an audible and / or visual alarm.

[0073] Monitoring elements are particularly capable of monitoring the proper functioning of cables, regardless of other cables and / or the cable's environment.

[0074] Cable structure

[0075] Various cable structures can be used to implement the methods according to the invention. The term "cable" should not be construed as limiting, but rather includes any elongated, flexible structure that can be wound and unwound.

[0076] The cable can be designed to withstand the pulling forces it may experience.

[0077] A predetermined potential can be applied directly to the cable, and the conductive portion of the cable is the entire cable. This cable can be, for example, a steel cable.

[0078] Alternatively, the cable may include at least one conductor raised to a predetermined potential, particularly at least one conductor different from the core or strands subjected to tensile force. Preferably, the cable includes at least two conductors, each raised to a predetermined potential. These two conductors may extend along the same section of the cable. Redundancy of the conductors particularly enables the detection of potential failure or degradation of at least one of the conductors. The two conductors may extend along two different sections of the cable, differing in length, width, and / or location along the cable. These sections may be connected together, partially overlap, or separate.

[0079] The cross-section of the cable is not limited to a circular cross-section. In fact, the cable according to the invention can particularly have a rectangular cross-section or a angular sector cross-section, and the cable can be, for example, in the form of a flat suspension belt. The cable can be a retractable belt between two boom cranes.

[0080] Cables can be steel cables, such as galvanized, braided multi-strand steel cables, or, for example, braided or unbraided steel strips with rectangular cross-sections, such as galvanized steel strips. Cables can also be in the form of rectangular cross-sections, perforated or unperforated metal strips. Cables can consist of glass fibers surrounded by a conductive film (such as aluminum or copper), which is protected by an insulator (especially rubber). Cables can be made of conductive rubber. This list is not limiting.

[0081] The cable can be bare or covered with an electrical insulator (such as vulcanized rubber) capable of withstanding the mechanical stresses associated with its function. The conductive portions are preferably covered with an electrical insulator.

[0082] Electrical insulators can in particular isolate cables, especially conductive parts, from electrical interference caused by contact with external components, especially systems used to guide, drive, and / or wrap the cables.

[0083] The cable includes, for example, at least one core, which is preferably adapted to withstand tensile forces, and the at least one conductive portion includes at least one electrical conductor that is different from the core.

[0084] The at least one electrical conductor of the cable may include one or more electrical conductors that are electrically insulated from and extend along the core, particularly wires, magnetic tapes, braided tapes or strips, and in particular, electrically insulated from the core by being covered by an electrical insulator, such as vulcanized rubber.

[0085] The electrical conductor can be an electrical wire (such as strands of copper wire) or a metal strip.

[0086] The electrical conductor can be wound in a spiral around the core. Advantageously, the spiral winding spacing is constant along the cable. The shorter the winding spacing, the greater the detection sensitivity. However, the longer the electrical conductor, the greater the self-capacitance. A compromise can be found to optimize the sensitivity of capacitance detection.

[0087] When the cable supplies power to a component moving through the cable, the component advantageously includes a grounded first conductive barrier covered by an insulator, which itself is covered by a second conductive barrier raised to a predetermined potential of the cable, also covered by an insulator. The grounding barrier shields against electrical interference caused by current cycling in the cable. The barrier raised to a predetermined potential improves the sensitivity of capacitance detection.

[0088] Components that move via cables can be powered by a power source configured to deliver DC voltage (e.g., about 24V or about 48V), single-phase AC voltage (e.g., about 230V), or three-phase AC voltage (e.g., about 400V).

[0089] The cable according to the invention is advantageously capable of transmitting DC voltage, single-phase AC voltage, or three-phase AC voltage, in particular.

[0090] In the case of DC voltage, the cable advantageously includes two conductive cores and a protective conductor (which is related to electromagnetic compatibility).

[0091] In the case of single-phase AC voltage, the cable advantageously comprises two conductive cores (one charged and one neutral) and a protective conductor (depending on the neutral mechanism selected and the protection of the connected terminal elements).

[0092] Alternatively, the conductive core and protective conductor carried by the same cable can also be carried by multiple different cables of the machine according to the invention, particularly by three different cables.

[0093] In one variation, the cable includes at least one protective conductor and four conductive cores, particularly three energized phases and a neutral core, the configuration of which depends on the chosen neutral mechanism (grounded neutral, ground-to-neutral, insulated neutral). Cables defined in this manner are particularly capable of transmitting three-phase AC voltage. Alternatively, as described above, these conductive cores and protective conductors can be carried by different cables for machines (parallel robots, cranes, boundary equipment, etc.).

[0094] The cable according to the invention can carry analog or digital signals through one or more conductors, which are preferably located in the core and covered by a grounded first conductive barrier, which is covered by an insulator, which is covered by a second conductive barrier raised to a predetermined potential, which is also covered by an insulator.

[0095] The cable may have at least two continuous sections that are electrically insulated from each other, the at least two continuous sections being subjected to a predetermined variable potential simultaneously or sequentially, thereby detecting the possible presence of a person, animal or object near each of these continuous sections and being able to locate a person, animal or object along the length of the cable.

[0096] The advantage of locating individuals, animals, or objects is that it can trigger the most suitable protective measures for the situation, such as modifying the cable trajectory when an obstacle is detected and located near a cable-driven parallel robot.

[0097] The method according to the invention advantageously includes the following steps: capacitance detection is performed on the one hand along the entire length of the cable, and on the other hand along at least one segment of the cable length, the position of which is known; more preferably, capacitance detection is performed on at least two consecutive segments of the cable length, the corresponding positions of which are known. This implementation provided by the invention enables a combination of redundancy and positioning.

[0098] Individuals, animals, or objects can be located relative to the cable and / or identified by at least one optical sensor, such as an image recognition system.

[0099] Capacitor Acquisition

[0100] The at least one conductive cable section can be raised to a predetermined potential V by being connected to an electronic circuit, including, in particular, a voltage generator.

[0101] For example, capacitance changes can be detected by measuring the current injected into the cable section.

[0102] The surface charge of the cable is generated by the current I, which can be indirectly defined by measuring the voltage at the terminals of the resistor connected in series with the voltage generator in the electronic circuit.

[0103] The sensitivity of the detection advantageously depends on the value of the current flowing in the cable and therefore on the potential to which the cable rises, the frequency of the voltage generator supplying the cable, and the resistance value. The sensitivity of the capacitance detection can be improved by increasing the value of the predetermined potential and / or the frequency and / or by decreasing the resistance value.

[0104] The predetermined potential is, for example, an AC voltage, preferably at a frequency between 10 kHz and 100 kHz, especially a sinusoidal voltage; the potential preferably has a peak-to-peak amplitude between 10 V and 100 V (inclusive).

[0105] The method according to the invention may include the following steps: performing a voltage measurement at the output of an electronic component (e.g., an instrumentation amplifier) ​​connected to a cable, thereby enabling monitoring of the current flowing through the electronic component to generate charge on the surface of the cable. Capacitance can be inferred from the measured voltage. The electronic circuit may include one or more operational amplifiers, such as JFETs.

[0106] The current measured at the surface of at least one conductive portion is advantageously less than 1 mA. Therefore, any accidental contact, especially accidental contact with a person, poses no danger.

[0107] For cables with lengths between 10m and 20m (inclusive), the capacitance can be less than 1nF, preferably less than approximately 100pF. For a 10kΩ resistor, the detection response time τ = R × C is relatively short, for example, equal to 1μs. This response time is beneficial for avoiding any collisions and for faster intervention in the event of, for example, intrusion.

[0108] The capacitive sensing response time is advantageously matched to the speed of cable movement and / or the speed of human walking movement.

[0109] For a predetermined unwound cable length l, in the absence of individuals, animals, or objects, the overall capacitance model of the capacitance detection device can be represented as follows:

[0110] [Mathematical Expression 1]

[0111] C(l)={(k×l+C0+C element )+C ext env}

[0112] Where k is the capacitance per unit length of the conductive cable, C0 is the capacitance generated by a set of stray capacitances, and C ext env C is the capacitance generated by electrical interaction with the static environment. element For the capacitance of a component fixed to a cable, particularly a basket and / or effector moving via the cable. The method preferably includes the step of minimizing stray capacitance C0, including capacitance C0 generated, for example, due to the presence of an electronic regulator in the electronic circuitry. p and / or the capacitance C of the section of cable wrapped around it. wound Compared to the capacitance of the unwound conductive cable section k×l, the capacitance C wound The preference is negligible, especially due to the barriers and grounding barriers raised to the predetermined potential. wound Preferably less than 10 pF.

[0113] Detection system

[0114] Another aspect of the invention is applied to a device, particularly a lifting machine or a cable-driven parallel robot, the device comprising at least one lifting or traction cable having at least one conductive portion and a detection system configured to raise the portion to a predetermined variable potential and detect a change in capacitance of the portion indicating the presence of an obstacle in the vicinity of the portion.

[0115] The device may include at least three lifting or traction cables, each having at least one sensitive conductive portion for capacitive detection of obstacles. Each cable may include at least one electrical conductor and an associated detection system. Thus, there may be as many detection systems as cables, operating simultaneously. These detection systems may share at least some processing circuitry, particularly for acting on the cable's drive mechanism upon detection of an obstacle. Similarly, there may be detection systems associated with at least two cables, connected together, for example, by an effector or basket to be moved, ensuring electrical continuity between the two cables.

[0116] Power can be supplied to the cable through components attached to it. For example, two cables can provide a live conductor and a neutral conductor respectively, with another cable providing a protective conductor. The power source can also be a low-voltage source.

[0117] Another aspect of the invention relates to a lifting or traction cable, the cable comprising at least one core subjected to traction force, at least one conductive shield electrically insulated from the core, and at least one electrically insulating detection conductor disposed outside the shield.

[0118] The cable may include at least two electrical conductors suitable for capacitance detection that extend together along at least a portion of the cable's length. Alternatively, the two electrical conductors suitable for capacitance detection may extend at different lengths of the cable.

[0119] These two electrical conductors can be simultaneously or sequentially raised to a predetermined variable potential, thereby performing capacitance detection according to the invention.

[0120] Another aspect of the invention relates to an apparatus corresponding to a boundary device, particularly a retractable safety barrier, comprising at least one boundary cable having at least one conductive portion, and a detection system configured to raise the portion to a predetermined variable potential and detect a change in capacitance of the portion indicating movement of a person, animal, or object near the portion relative to the portion. In more complex variations, such an apparatus according to the invention may also, according to at least one embodiment described above, supply power via DC or AC voltage to at least one system (e.g., a light and / or sound warning system) connected thereto, integrated into the cable, or external to the device, and / or may further include at least one monitoring element as described above. Attached Figure Description

[0121] The invention can be better understood by reading the following detailed description of non-limiting embodiments and by examining the accompanying drawings, in which:

[0122] [ Figure 1 ] Figure 1 Partially and schematically illustrating a cable-driven parallel robot device according to the present invention,

[0123] [ Figure 2 ] Figure 2 This illustrates powering a cable via a voltage generator.

[0124] [ Figure 3 ] Figure 3 It shows what happens when a person, animal, or object approaches. Figure 2 The reaction of the cables in the middle,

[0125] [ Figure 4 ] Figure 4 This represents the evolution of electric field strength and voltage with respect to the distance from the cable.

[0126] [ Figure 5 ] Figure 5 The effect of a barrier on a portion of a cable, with that portion of the cable positioned to face the barrier, is shown.

[0127] [ Figure 6 ] Figure 6 This schematic diagram illustrates a system for winding electrically insulated cables.

[0128] [ Figure 7 ] Figure 7 The variant of the device according to the present invention is similar to Figure 1 The view,

[0129] [ Figure 8 ] Figure 8 Partially and schematically, a variant of the device that performs testing on two cables is shown.

[0130] [ Figure 9A ] Figure 9A This is a cross-sectional view of a cable example.

[0131] [ Figure 9B ] Figure 9B This is a cross-sectional view of a cable example.

[0132] [ Figure 9C ] Figure 9C This is a cross-sectional view of a cable example.

[0133] [ Figure 9D ] Figure 9D This is a cross-sectional view of a cable example.

[0134] [ Figure 9E ] Figure 9E This is a cross-sectional view of a cable example.

[0135] [ Figure 9F ] Figure 9F This is a cross-sectional view of a cable example.

[0136] [ Figure 9G ] Figure 9G This is a cross-sectional view of a cable example.

[0137] [ Figure 9H ] Figure 9H This is a cross-sectional view of a cable example.

[0138] [ Figure 9I ] Figure 9I This is a cross-sectional view of a cable example.

[0139] [ Figure 9J ] Figure 9J This is a cross-sectional view of a cable example.

[0140] [ Figure 9K ] Figure 9K This is a cross-sectional view of a cable example.

[0141] [ Figure 9L ] Figure 9L This is a cross-sectional view of a cable example.

[0142] [ Figure 9M ] Figure 9M This is a cross-sectional view of a cable example.

[0143] [ Figure 9N ] Figure 9N This is a cross-sectional view of a cable example.

[0144] [ Figure 9O ] Figure 9O This is a cross-sectional view of a cable example.

[0145] [ Figure 9P ] Figure 9PThis is a cross-sectional view of a cable example.

[0146] [ Figure 10 ] Figure 10 This illustrates the use of three cables to power a load fixed to those cables.

[0147] [ Figure 11 ] Figure 11 The illustration shows an example of a cable capable of locating a person, animal, or object.

[0148] [ Figure 12 ] Figure 12 This refers to the electronic circuitry used to provide dual detection.

[0149] [ Figure 13 ] Figure 13 A block diagram illustrating an example of a device according to the invention.

[0150] [ Figure 14 ] Figure 14 An example showing the trajectory of two cables fixed to a load.

[0151] [ Figure 15 ] Figure 15 It is a table that groups the relative humidity data recorded during the calibration process, independent of the surrounding environment.

[0152] [ Figure 16 ] Figure 16 An example of reference data presented in tabular form for converting voltages required for eight cables, each cable comprising two electrical conductors performing a predetermined movement.

[0153] [ Figure 17 ] Figure 17 It is a graph showing the evolution of cable capacitance for different areas of a person, animal, or object.

[0154] [ Figure 18 ] Figure 18 The diagram shows different relative configurations of cables and people.

[0155] [ Figure 19 ] Figure 19 A schematic representation of an electrically insulated winding drum.

[0156] [ Figure 20 ] Figure 20 A schematic representation of an electrically insulated pulley.

[0157] [ Figure 21 ] Figure 21 The retractable safety barrier device according to the present invention is illustrated schematically.

[0158] [Figure 22a] Figure 22 schematically illustrates a scenario of personal intrusion.

[0159] [Figure 22b] Figure 22b schematically illustrates a person's proximity to a cable.

[0160] [ Figure 23 ] Figure 23 The diagram schematically illustrates a loop around a cable according to the present invention.

[0161] [ Figure 24 ] Figure 24 Partially and schematically, a variant of the device that performs testing on two cables is shown.

[0162] [ Figure 25 ] Figure 25 A schematic block diagram illustrating an example of a device according to the present invention.

[0163] [ Figure 26 ] Figure 26 An example of a signal conditioner,

[0164] [ Figure 27 ] Figure 27 The two cables connecting the device according to the invention to the signal conditioner are shown.

[0165] [ Figure 28 ] Figure 28 An example of a signal conditioner,

[0166] [ Figure 29 ] Figure 29 A schematic diagram illustrating an example of a device according to the present invention. Detailed Implementation

[0167] Figure 1 The image schematically and partially illustrates an example of a cable-driven parallel robot 1 according to the present invention, which includes a support structure 32, a winding system 31, and a cable 10, at least a portion 10a of the cable 10 being conductive.

[0168] Components, particularly load 11, can be fixed to the far end of the cable. Other cables connecting the robot to load 11 are not shown.

[0169] Advantageously, the winding system 31 is positioned on top of the support structure 32, which not only reduces the length of the cable 10, but also reduces electromagnetic interference and capacitive effects on the cable 10.

[0170] In a variant not shown, the winding system 31 is also located on the support structure 32, for example, at the bottom of the support structure 32. Figure 1 As shown, the length l of the conductive part can be less than the length L of the cable. Figure 1 For example, the ends of the cable are not conductive.

[0171] The winding system 31 may include a motorized winder and / or an encoder to determine the length of the unwound cable.

[0172] Preferably, the encoder is an absolute encoder implemented at the level of the winding system 31.

[0173] The conductive part 10a emits a radial electric field around it. The presence of an obstacle causes a change in the electric field, and thus a change in the capacitance of the cable.

[0174] The capacitance C of a cable is essentially proportional to the unwound length l of the conductive cable section that is sensitive to capacitive effects. This length l may change when the cable 10 is dragged or when the load 11 is raised or lowered. The capacitance of the cable can be estimated using the formula C(l) = k × l, where k is the capacitance coefficient per unit length.

[0175] Figure 2 This is a highly schematic illustration of connecting to the internal resistor r G voltage generator V G The conductive cable 10 is raised to a predetermined potential V. According to Coulomb's law, the repulsive force of the surface charge is equal to the injection force of the generator. For a sine wave generator, the cable 10 is in electrostatic equilibrium or quasi-static equilibrium. The surface charge is then uniformly distributed along the entire length L of the cable 10.

[0176] Figure 3 This indicates a location near a person, animal, or object 20, similar to Figure 2 Cable 10 is a cable in the circuit. The charge on the surface of the cable is no longer uniformly distributed. According to the theory of corresponding elements, the charges with opposite signs on the surface of the person, animal, or object react with the cable. The surface charge of cable 10 no longer opposes the injection force of the generator, which then injects a new charge equal to the amount of charge interacting with the person, animal, or object 20. The capacitance can then be estimated using the following formula: C = C self +C ext env +C ind,ani,obj C self The self-capacitance of the structure, in this example, is cable 10, C. ext env The capacitance of the static environment is considered to be zero in this example, and C ind,ani,obj Let 20 be the capacitance of a person, animal, or object. Then, an increase in charge density Q + ΔQ can be observed, and thus an increase in capacitance C + ΔC and an increase in the current supplied by the generator to produce electrical energy I + ΔI. For a predetermined distance d between the person, animal, or object and the cable, a fixed cable length L, and a cable radius r, the charge density can be defined by the following formula:

[0177] [Mathematical Expression 2]

[0178] Q = I × t = 2πrLσ = C × V

[0179] Where σ is the surface charge density of the conductive cable portion and t is time. Capacitance can be defined mathematically as follows:

[0180] [Mathematical Expression 3]

[0181]

[0182] Where ε0 is the vacuum permittivity and d ∞ For the distance, C(d) ∞ )≈0.

[0183] Distance d ∞ For example, it is approximately 0.5m. Distance d ∞ Preferably greater than 2m, even better than greater than 3m.

[0184] exist Figure 3 The person, animal, or object 20 is schematically represented, for example, a person. In particular, the electrical influence of the person, animal, or object on the cable varies by 1 / d, where d is the distance from the person, animal, or object.

[0185] The portion of the cable wound around the winding system 31 does not pose any danger to the obstacle. However, this portion of the cable may be subject to electrical influences from the mechanical components constituting the winding system 31. These electrical influences may create capacitive coupling that interferes with capacitive detection of the obstacle.

[0186] For these reasons, preferably, the winding system 31 is Figure 1 The protection system 40 shown reduces the surface charge density on the portion of the cable wound onto the winding system. The protection system 40 preferably includes a barrier 41 that is raised to a predetermined voltage V of the cable and is surrounded by a grounded shield 42.

[0187] Figure 6 An example of a winding system 31 for cable 10 is shown, which includes one or more pulleys 71 surrounded by a protection system 40 and a winder 72. The protection system 40 includes: a barrier 41 raised to a predetermined potential of cable 10, thereby reducing the surface charge density of the cable portion positioned facing the barrier 41; and a grounded shield 42 surrounding the barrier 41 and preventing the cable from being subjected to electromagnetic interference and external capacitive coupling.

[0188] Figure 5 The effect of the barrier 41 positioned facing the cable portion 10 is schematically shown. Figure 5In the example, barrier 41 is raised to a predetermined potential V of the cable via a voltage follower. The surface charge density σ' of the cable portion 10b of length l' is less than the surface charge density σ' of the conductive cable portion 10a not positioned to face the barrier raised to the predetermined potential V. In fact, the cable portion 10b facing barrier 41 is at the same potential V as barrier 41, and they are under total electrical influence. Therefore, no charge is stored on the surface of this cable portion 10b. Thus, the capacitance of the portion 10b of length l' facing barrier 41 becomes negligible compared to the capacitance of the cable portion 10a of length l not positioned to face barrier 41.

[0189] [Mathematical Expression 4]

[0190] C(L)=C(l)+C(l′)≈C(l)=k×l

[0191] The lower the surface density σ' compared to the surface density σ, the higher the relative sensitivity of capacitance detection of the cable portion 10a that is not placed facing the barrier 41 and rises to the predetermined potential V.

[0192] The sensitivity of capacitance detection also depends on the distance d of the person, animal, or object 20 relative to the cable 10.

[0193] Figure 7 express Figure 1 A variation of structure 1. In this example, a load 11 fixed to the distal end of cable 10 is raised to a predetermined potential V of the cable. The conductive cable portion corresponds to the entire cable. Load 11 becomes sensitive to the proximity of obstacle 20 through capacitance detection. Figure 6 As in the example, the cable portions in contact with the support structure 32 and / or the winding and drive system 31 are electrically insulated by a barrier 41 and / or a grounded shield 42 that raises the potential V of the cable.

[0194] The cable portion in contact with the support structure 32 can be located inside a barrier raised to a predetermined potential V of the cable 10. Fixtures (if present) and the load can be covered with a conductive material, such as conductive paint or conductive rubber. Thus, the formula C(l) = k × l + C can be used. load To estimate the capacitance of the sensitive system used for capacitance detection, where C load The capacitor is related to load 11.

[0195] like Figure 10As schematically shown, a cable-driven parallel robot may include at least three cables 101, 102, and 103, through which electrical power can be supplied to a load 11. One cable may provide a live conductor, another a neutral conductor, and the third a protective conductor. For example, the load 11 may be supplied with an AC voltage of 230V, a frequency of 50Hz, and a root mean square current of 3A.

[0196] Alternatively, power can be supplied to load 11 via two cables or one cable.

[0197] For example, DC voltage power is supplied to load 11 through two cables.

[0198] Advantageously, at least one cable is configured to transmit signals, for example, by optical transmission or power line carrier current.

[0199] Preferably, the cable-driven parallel robot includes at least four cables.

[0200] Preferably, the cable includes a core composed of strands of conductive copper wire capable of providing a phase conductor, neutral conductor, or protective conductor. The diameter of the stranded copper wire can be approximately 0.8 mm. The stranded copper wire is preferably surrounded by an insulator, and a shielding material is preferably surrounding the copper wire, and the insulator is preferably surrounding the shielding material. The total thickness of the insulator and shielding material is approximately 0.6 mm, thus the diameter of the stranded copper wire having the insulator and shielding material is approximately 2 mm.

[0201] Figure 8 Indicates something similar to Figure 7 The cable consists of two cables, 101 and 102, which work together to manipulate the load 11 connected to them. Each cable is at a predetermined potential. Cables 101 and 102 have self-capacitances C1 and C2, respectively.

[0202] The interaction between cables 101 and 102 may interfere with obstacle detection. A predetermined potential can be determined for each cable to limit these electrical effects on other cables and / or ground and / or load and / or basket and / or fixtures, particularly by changing the predetermined potential.

[0203] Alternatively, one or more sections of conductive cable may be subjected to variable potentials of corresponding frequencies from each other. In particular, frequencies with a non-integer ratio between them may be selected to prevent interference caused by harmonics.

[0204] Alternative locations can be used to account for interference related to other cables and / or grounds and / or loads and / or baskets and / or fixtures when acquiring and storing reference data and then by comparison.

[0205] Figure 24 express Figure 8 A variation of the structure includes two cables 101 and 102, each with capacitors C1 and C2 respectively. Each support structure 32 includes a winding system 31 with an encoder 33, which preferably includes a motorized winder. Cables 101 and 102 have, for example, a length L of about 10 m and a radius r less than or equal to 4 mm.

[0206] Cables 101 and 102 preferably each include at least two detection conductors, which are preferably electrically insulated, and preferably electrically insulated by coating with vulcanized rubber.

[0207] In addition, Figure 24 In the example, load 11 is provided with at least two electrical conductors, each of which is an extension of one of cables 101 and 102. Load 11 is permanently connected to the cable, for example, as a pallet fixed to the cable. Alternatively, load 11 is removably attached to the cable, with the electrical conductors of the load temporarily connected to the electrical conductors of each cable.

[0208] Reference data

[0209] Cable-driven parallel robots can perform a wide variety of tasks, such as painting various parts of an aircraft or manipulating large and / or heavy loads. Depending on the application, cable-driven parallel robots are equipped with different fixtures and produce different trajectories. Similarly, safety barriers can be installed for various reasons, and detection may be used to detect changes in specific types of individuals or, in particular, changes in the cable environment, such as corresponding to a person crossing a fence or an animal approaching a danger zone.

[0210] Performing at least one learning phase enables adaptation to these diverse applications. This learning phase includes acquiring reference data, which is application-specific and subsequently used as comparison data to detect obstacles, or even identify obstacles and / or determine distances to obstacles.

[0211] Figure 14 An example of obtaining reference data for a predetermined cable movement is shown, where the cable is, for example, part of a cable-driven parallel robot, and a person, animal, or object represents a potential obstacle. This movement is, for example, from point M1 to point M... n Passing through point M i and M j The trajectory is defined from point M. i Move to the next point M j For example, the change in length l1 and l2 of at least one cable 101 and 102, denoted by Δl, can be expressed as Δl = ±1 cm. Point M can be represented in the following way. iThe coordinates are defined as Cartesian coordinates:

[0212] [Mathematical Expression 5]

[0213]

[0214] Among them, Ψ i θ i , The rotation angle, precession angle, and coiling angle of cables 101 and 102 relative to the support structure 32.

[0215] exist Figure 15 The data represented in the table constitutes an example of reference data, which is obtained by causing the cable and / or the load attached to the cable to make a predetermined movement, thereby enabling capacitance changes due to the presence of a static environment in which the cable moves to be taken into account.

[0216] The degree of change can be determined, thereby limiting the expected capacitance change for a decrease or increase of l ± Δl in the length of a cable. In particular, using the degree of capacitance change allows for the neglect of interferences that are slow compared to the acquisition time, especially changes in relative humidity.

[0217] Figure 15 The data shown can be derived from the calibration of a cable-driven parallel robot comprising p cables. For each cable j (j in the range [1, p]), at point M... i The voltage is measured at a point (i is in the range [1, n]). Based on this data, ΔV can then be determined. S,j (M i+1 –M i ), which represents two consecutive positions M i and M i+1 The degree of voltage change between points. To determine the presence of an obstacle, a reference rate of change can be compared with the voltage measured at time t, preferably the current time:

[0218] [Mathematical Expression 6]

[0219] ΔV S,j [(M i+1 ,t)-(M i ,t)]-ΔV S,j [M i+1 -M i ]=Δ[ΔV S,j (M(t))]

[0220] To compare the voltage of the reference data with the voltage measured at time t, the voltage at point M can be calculated for a cable j of length l. i Normalization level at:

[0221] [Mathematical Expression 7]

[0222]

[0223] Here, K is a coefficient related to capacitance-to-voltage conversion, for example, depending on the electronic regulator. This level of calculation not only allows for the neglect of changes in the relative humidity of the surrounding environment but also eliminates the dependence on the unwinding length of the cable.

[0224] To ensure safety redundancy, each cable j may include at least two electrical conductors for capacitance detection, such as at least two wires, for example, wires spirally wound along the cable. Each conductor has its own inductance. The capacitances of the conductors within the same cable are preferably similar, and preferably equal. Comparing the capacitances of the cable conductors enables the detection of the presence of a fault.

[0225] Figure 16 The table shows reference data for obtaining a given trajectory of a structure comprising eight cables connected in parallel, each cable including two electrical conductors. The first row corresponds to the acquisition of the capacitance converted to voltage for the first conductor of each cable when the junction of the eight cables or the center of gravity of the load fixed to the eight cables is located at point M1. The second row corresponds to the acquisition of the capacitance converted to voltage for the second conductor of each cable when the junction of the eight cables or the center of gravity of the load fixed to the eight cables is located at point M1.

[0226] The conductors of the same cable have substantially equal capacitance, which is advantageous. Figure 16 The values ​​in the first row of the table are basically equal to the values ​​in the second row of the table.

[0227] Acquiring reference data can also determine capacitive fingerprints associated with a specific individual, animal, or object. Reference data characteristics of the capacitive fingerprint of a person can be acquired for a predetermined set of distances between the person and the cable, for example, for distances less than 50 cm, such as at intervals of approximately 5 cm. Preferably, the maximum distance is such that C(d) ∞ The distance is approximately 0.

[0228] Figure 17 An example of reference data measurement performed on a fixed-length cable 10 when a person 20 approaches the cable 10 is shown. Detection of a person, animal, or object 20 near the cable 10 allows it to be claimed that the person, animal, or object 20 is located at a distance less than or equal to the capacitance detection range, i.e., d ≤ d0. ∞ To determine the distance *d* of a person, animal, or object from the cable, the measured capacitance change can be compared to reference data, such as data at constant distance intervals Δd. H The measured voltage values ​​are preferably sufficiently close together due to negligible changes in relative humidity.

[0229] [Mathematical Expression 8]

[0230]

[0231] For example, regarding d ∞ Equal to approximately 30cm, or better yet, approximately 50cm, C(d) ∞ )≈0 and V S (d ∞ ) l ={(k×l+C load )+C ext env}

[0232] When a person, animal, or object, especially a person, is from d ∞ Approaching distance Δd H At that time, its impact can be calculated:

[0233] [Mathematical Expression 9]

[0234] V S (d ∞ -Δd H ) l =V S (d H ) l =K×[{(k×l+C load )+C ext env}+C(d H )]

[0235] This can be repeated when a person, animal, or object, especially a person, moves from a previous position. ∞ -(n-1)Δd H 10 meters away from the cable Δd H The steps to calculate its impact:

[0236] [Mathematical Expression 10]

[0237] V S (d ∞ -nΔd H ) l =K×[{(k×l+C load )+C ext env}+C(d H )]

[0238] A person, animal, or object 20 with a fixed surface area and located at a distance d from the cable 10 causes a capacitance change in the cable that is advantageously always the same, in particular a capacitance change that does not change with the length of the cable.

[0239] However, the reference data characteristics of the capacitive fingerprints of people vary significantly from each other depending on, for example, the area and / or height of the people. Therefore, in order to establish reference data, it is advantageous to determine the upper and lower limits of the voltage change. The upper and lower limits can be determined by adding or subtracting a certain percentage value, for example 5%:

[0240] [Equation 11]

[0241] V s (d human ) = V s (d human ) ± 5%

[0242] The influence ΔC of a person on the capacitance of the cable human will always be the same regardless of the sensitive length l of the unwound cable. Therefore, the sensitivity of the capacitance detection for the approach of a person, more generally an individual, an animal or an object, depends on the capacitance detection of the unwound length l of the cable:

[0243] [Equation 12]

[0244]

[0245] The sensitivity is between 0.6% and 4.8% (including 0.6% and 4.8%) for 0 < l < 1m, between 0.5% and 3.34% (including 0.5% and 3.34%) for 1 < l < 5m, between 0.45% and 3% (including 0.45% and 3%) for 5 < l < 10m, d H is between 5cm and 30cm (including 5cm and 30cm), the total length of the cable is 15m and the radius of the electrical conductor is 2mm.

[0246] Alternatively, multiple measurements can be performed to determine the minimum capacitance change and the maximum capacitance change depending on the distance d of the individual, animal or object 20 from the cable 10 and its surface area and / or height when the individual, animal or object 20 is present.

[0247] In the Figure 17 example, three acquisitions were performed for different surface areas S min , S max , S mean of the individual, animal or object 20, so as to be able to define the lower limit C min and / or the upper limit C max of the capacitance change. In fact, the surface area of the person 20 causes a capacitance change of the cable 10, which may change depending on the posture of the individual, for example, as Figure 18As shown, an individual's posture is one in which their arms are extended, along their body, or away from their body. Multiple acquisitions can also be performed for the same type of individual, animal, or object 20 (e.g., people), where the individuals, animals, or objects have different surface areas (e.g., at least two people of different heights or different builds).

[0248] When detected at the minimum limit C min and maximum limit C max Between (including C) min and C max When the capacitance changes, advantageously, a predetermined action is triggered, particularly selected from: generating a visual, audible, or tactile alarm, stopping the movement of the cable and / or components driven by the cable, and preventing startup and / or restart. Preferably, a change greater than the maximum change limit C is detected. max The change in capacitance triggers an automatic stop to the cable movement.

[0249] The capacitance change can also be defined by the relative sensitivity, which depends on the length l of the conductive cable section, for example, by τ = C. ind,ani,obj (d) / C self (d,l) are defined. Therefore, for a cable length l, an action can be triggered if a capacitance change greater than or equal to τ is detected.

[0250] electric field

[0251] Figure 4 The curve in the figure represents both the variation of the electric field intensity emitted by the conductive cable portion with distance from the cable and the field strength converted into voltage. For a fixed cable length, the intensity of the emitted electric field can be defined by the following formula:

[0252] [Mathematical Expression 13]

[0253]

[0254] Where σ is the surface density of the conductive part.

[0255] The conversion from electric field to voltage is defined by the following formula:

[0256] [Mathematical Expression 14]

[0257]

[0258] The electric field strength depends in particular on a predetermined potential V on the conductive portion of the cable. By changing the predetermined potential V, the detection range of environmental changes of the cable can be increased or decreased.

[0259] The conductive cable section is equivalent to a wire antenna with a shielded transmitting cable. That is, the root mean square value of the current is essentially constant along the entire length of the relevant cable section before decreasing to zero at the end of the relevant cable section.

[0260] Cable structure

[0261] Figure 9A , Figure 9B , Figure 9C , Figure 9D , Figure 9E , Figure 9F , Figure 9G , Figure 9H , Figure 9I , Figure 9J , Figure 9K , Figure 9L , Figure 9M , Figure 9N , Figure 9O , Figure 9P This illustrates various possible structures for traction or lifting cables according to the present invention. These cables are emitted as follows: Figures 9A-9D The radial electric field E is shown.

[0262] The traction or lifting cable according to the invention is preferably configured to support a traction force of at least 100 daN and preferably up to 800 daN. The traction or lifting cable according to the invention is preferably configured to withstand a force of at least 100 kgf and preferably up to 800 kgf.

[0263] The cable is preferably configured to break only when a load greater than or equal to 1000 daN is applied. The cable is preferably configured to break only when the force is greater than or equal to 1000 kgf.

[0264] Cables can be configured to have a safety margin of at least 2, meaning that the ratio between the load the cable bears during its normal use and the load that would cause the cable to break is at least 2.

[0265] The cable can be configured to be wound around a roller having a diameter of, for example, about 20 cm.

[0266] The cable can have a predetermined potential applied directly to it, and the conductive part of the cable is thus the entire cable.

[0267] Figure 9A This refers to a cable of the following type, comprising an insulating sheath 12 and a shield 13, which emits an electric field E generated by a direct connection between the cable and a voltage generator, such as in... Figure 2 The example is illustrated illustratively.

[0268] The insulating sheath 12 can be a polyurethane sheath.

[0269] Figure 9B , Figure 9C and Figure 9D This refers to a cable comprising at least a core 15 and at least one conductive shield 13, the core 15 being designed to withstand tensile forces, and the conductive shield 13 being electrically insulated from the core, particularly through an insulator 14.

[0270] Figure 9D The cable shown is relative to Figure 9B The advantage of the cable in this case is that it can generate a larger capacitance detection range when both cables are raised to the same potential V. The capacitance detection range can be advantageously increased or decreased by reducing or increasing the area occupied by the shield 13 in the cable.

[0271] The self-capacitance of the electrical conductor is preferably less than 150 pF, and more preferably less than 110 pF. The lower the self-capacitance of the electrical conductor, the greater the potential to improve the sensitivity of capacitance detection and increase the capacitance detection distance.

[0272] like Figures 9B to 9J As shown, the cable advantageously includes an insulator 12 outside the shield 13.

[0273] The cable may include at least one conductor 16 raised to a predetermined potential. Preferably, the cable includes at least two conductors, each raised to a predetermined potential. These two conductors may extend along the same portion of the cable or along two different portions of the cable.

[0274] Figure 9I and Figure 9J This refers to a cable comprising two sheathed cores 15a and 15b with circular cross-sections, or two sheathed cores 15a' and 15b' with semi-circular cross-sections. The cores may be spirally wound. The combination of two cores may be covered by an insulator 12. The presence of at least two cores provides safety redundancy. The insulating coating 12 may include at least one electrical conductor 16.

[0275] Figure 9E , Figure 9F , Figure 9G and Figure 9H This refers to a cable comprising at least one core 15 and an insulator 12, the core 15 being able to withstand tensile or lifting forces, and the insulator 12 surrounding the core. At least one electrical conductor 16 is embedded in the insulator 12.

[0276] Figure 9EThis refers to a cable capable of withstanding traction or lifting forces. The cable includes a core 15, made of, for example, steel and covered by an insulator 12, capable of supporting the cable under normal mechanical forces. The insulator 12 is made of, for example, rubber. In this example, two wires 16, embedded in the insulator, are spirally wound along the core. Each wire can be connected to a capacitance detection system.

[0277] Figure 9G This refers to a cable comprising two strip-shaped electrical conductors 16 embedded in an insulator 12. These conductors 16 can be as follows: Figure 9G They are arranged concentrically as shown. The two electrical conductors 16 can be opposite each other in diameter. Figure 9H This also refers to a cable that includes two strip conductors 16 and an insulator 12. The insulator 12 may be formed from two different shells separated by the two conductors, which extend radially from the core 15 to the outer surface of the insulator 12.

[0278] Figure 9G The cable in the core 15 is capable of transmitting analog or digital signals through at least one conductor 17 located in the core 15. The conductor 17 is preferably covered by an insulator. The conductor may be a copper wire (e.g., stranded copper wire), preferably having a diameter of approximately 0.2 mm, and preferably covered by an insulator. The insulator may be a sheath having a thickness of, for example, approximately 0.3 mm. Alternatively, the conductor may be an optical fiber covered by an insulating sheath.

[0279] The core of the cable according to the invention can be used to supply electrical energy (medium voltage, single-phase or three-phase current) to a load 11 fixed to the cable. It can also supply low voltage power to a load 11 fixed to the cable.

[0280] Figure 9F This describes a cable structure capable of supplying electrical energy to a load 11 fixed to the cable. The cable comprises three cores 15a, 15b, and 15c, insulated from each other, which respectively provide a live conductor, a neutral conductor, and a protective conductor. The cross-sectional shape of these three cores 15a, 15b, and 15c is preferably an identical angular sector surrounded by a grounding barrier 18, which is surrounded by an insulator. This insulator is itself surrounded by a barrier 19 that raises the potential to the cable and is covered by the insulator. Thus, the wire embedded in the insulator 12 is protected from the electrical effects caused by supplying electrical energy to the load 11 through the cores 15b and 15c.

[0281] The cable according to the invention may include a set of strands, each strand consisting of a set of conductors, such as galvanized steel wire. Figures 9K to 9NAs shown in the example, the cable comprises, for example, 6 or 7 strands, each strand comprising 7 to 19 conductors, and the cable has a diameter d between 4 mm and 8 mm (inclusive). c The cable is preferably surrounded by an insulator 12, the thickness of which is, for example, between 1 mm and 2 mm (inclusive).

[0282] exist Figures 9K to 9N In the example, the cable consists of 7 strands, and each strand consists of 7 conductors.

[0283] exist Figure 9K In the example, each conductor of each cable strand is raised to a predetermined variable potential and subjected to AC voltage. This type of cable can have high safety redundancy.

[0284] exist Figure 9L In the example, the stranded electrical conductor 16 is located around the cable strands, and the strands of the conductor 16 are preferably interlaced around the cable strands in a spiral manner, with the spacing depending on the winding spacing of the strands. The diameter d of one strand of the conductor 16 b It can be approximately 0.3mm.

[0285] exist Figure 9M In the example, the cable includes two stranded electrical conductors 16 located around the strand, thus enabling safety redundancy.

[0286] The strands are preferably surrounded by an insulator.

[0287] Each strand can be at a predetermined potential and thus form a detection conductor.

[0288] Alternatively, multiple strands of wire can be combined to form an electrical conductor. Therefore, as... Figure 9N As shown, the cable comprises two electrical conductors, each formed by three strands. Other combinations of strands are also possible, such as groups of three adjacent strands. Figures 9K to 9N In the example cable, one of the strands can be composed of stranded conductive copper wires to be able to supply power to the load 11.

[0289] Figure 9O and Figure 9P This indicates a variation of this type of cable.

[0290] exist Figure 9O In this configuration, the central strand is a strand of copper wire surrounded by a first grounding shield, which itself is surrounded by a barrier that raises the potential of the other strands.

[0291] Alternatively, the grounding shield can be replaced by a band-stop filter located at the output of a signal conditioner connected to the electrical conductor, for example, the frequency of the band-stop filter is 50Hz for a current passing through the electrical conductor at 50Hz.

[0292] When the cable includes at least one detection conductor that is different from the strands and the wires constituting the strands, such as Figure 9L and Figure 9M As shown in the example, strands of copper power lines can be surrounded by a single grounded shield, and the strands can be raised to the potential of the electrical conductor. One such example is... Figure 9P As shown in the image.

[0293] Generally speaking, a cable may include at least one core for withstanding tensile forces, a detection conductor different from the core, and a signal transmission conductor surrounded by a grounded shield, with the core located around the shield and at the potential of the detection conductor, the detection conductor located around the core, and an insulator surrounding the detection conductor.

[0294] In a preferred embodiment, the cable includes at least two electrical conductors for capacitance detection and at least one wire for supplying power to the load 11, the wire being surrounded by a grounded shield, which itself is surrounded by a barrier that raises the potential of the electrical conductors, the electrical conductors being located around the barrier.

[0295] The aforementioned cable structures enable the detection of individuals, animals, or objects near the cable. However, these cable structures cannot locate individuals, animals, or objects along a conductive portion of the cable. To enable the location of individuals, animals, or objects along the cable, preferably along its entire length, multiple sensitive elements for capacitance detection can be positioned on a portion of the cable, such as a continuous section, preferably separated by an insulator. Examples of such cable structures are shown in... Figure 11 As shown in the image.

[0296] Sensing elements 61a, 61b, and 61c are segmented along the cable and isolated from each other by isolating elements 62a and 62b. Each sensing element is connected to module 65 of a detection system capable of detecting the proximity of a person, animal, or object. After grouping information from the various detection modules 65 and processing that information, for example, a processor, the position of the person, animal, or object along the cable can be defined. Adjustment circuitry connected to the detection module 65 can be multiplexed to differentiate the individual sensing elements along the cable.

[0297] Figure 12 It is able to follow like Figure 9EAn example of an electronic circuit for capacitance changes in the two conductors 16a and 16b of the cable is shown. Specifically, the electronic circuit includes an electrical regulator connected to the conductors, which converts the capacitance of the conductors into voltage. The presence of at least two conductors 16a and 16b enables safety redundancy for the detection of persons, animals, or objects. The cable is advantageously configured to respond to faults. The two conductors can generate the same electric field. Then, in the absence of persons, animals, or objects, the two conductors 16a and 16b send the same information. In the event that the information sent by the two conductors differs, an alarm signal can be generated and / or shutdown or maintenance measures can be applied. Different information can be caused by the presence of a person, animal, or object, damage to the conductors, a fault, or any other incident that prevents at least one of the conductors from detecting environmental changes in the cable.

[0298] When operating normally and in the absence of individuals, animals, or objects, the electrical conductor preferably always transmits the same information.

[0299] By comparing the information transmitted by the electrical conductor with the information transmitted by at least one reference electrical conductor and / or predetermined reference data, a damaged electrical conductor, a fault, or any other incident that prevents at least one of the electrical conductors from detecting environmental changes in the cable can be identified.

[0300] For example, in Figure 12 In the electronic circuit, R1 = 1kΩ and R2 = 10kΩ. Therefore, for a frequency of 100kHz, I < 1mA, and the peak-to-peak voltage is 100V. This current poses no danger to a person upon contact.

[0301] The electronic circuit may include a high-pass filter for filtering, particularly of the 50Hz trunk line. Conductors 16a and 16b may be protected from electrical influences, for example, caused by the supply of power to the load 11 from the core of the cable.

[0302] Each cable is preferably connected to a signal conditioner. Each cable can be connected to the signal conditioner via a Bayonet Neill-Concelman (BNC) connector. Therefore, the device according to the invention preferably includes at least the same number of signal conditioners as the number of cables. Figure 19 and Figure 20 As shown, the insulator can cover any cable guiding, driving, and / or winding system.

[0303] exist Figure 19 The image shows a winding drum 72 covered by an insulator 82.

[0304] exist Figure 20The image shows a pulley 71 covered by an insulator 82. The pulley 71 may be made entirely of insulating material. Alternatively, the pulley 71 may be made of metal covered by the insulating material 82; this metal may be raised to the potential V of the cable or rectified by a barrier 41 raised to the potential V of the cable, wherein the cable is preferably covered by an insulator.

[0305] like Figure 23 As shown, cable 10 may also include at least one element 91 capable of monitoring the function of the cable, for example, when the cable is used in lifting or traction equipment or boundary equipment. In particular, this element is preferably a metal ring surrounding the cable. Specifically, this element may be detected by an electromechanical or inductive sensor located at the entrance of the cable guiding, driving, and / or winding system or near the cable. The element 91 may also be an RFID tag attached to the cable, and the sensor located at the entrance of the cable guiding, driving, and / or winding system or near the cable is an RFID reader.

[0306] Figure 21 An example of a safety barrier device according to the invention is shown, which includes a cable 10 extending between two support structures 32. This type of structure is configured to detect changes in the environment, particularly if a person 20 approaches the safety barrier formed by the cable 10 (as shown in FIG. 22b), or if the person 20 crosses the safety barrier formed by the cable 10, for example, passing under the cable (as shown in FIG. 22a) or over the cable.

[0307] Advantageously, the capacitive effect of the support structure 32 can be considered in the static environment of the cable.

[0308] The system 31 for winding the cable 10 can be positioned in at least one support structure 32, which is preferably surrounded by a protective system 40.

[0309] Figure 13 This is a schematic block diagram illustrating an embodiment of the method of the present invention. The generator supplies power to one or more capacitive sensors located on one or more cables of a robot, lifting and / or traction machine, or safety barrier.

[0310] The processing system may include a processor (particularly a microcontroller) and a data analyzer, particularly for analyzing changes in current flowing through cables. Specifically, by comparing measured voltage, current, or capacitance with reference data, it can determine the presence of a person, animal, or object, better locate the person, animal, or object, better locate the person, animal, or object along at least one cable, and even better estimate the distance of the person, animal, or object from the cable. Furthermore, an alarm system is connected to the processing system. The alarm system may be an audio system and / or a visual system. The processing system can also be connected to the robot's control interface, and emergency measures, particularly emergency stops or trajectory modifications, can be programmed onto the processing system.

[0311] Figure 25 A schematic block diagram illustrating an example of a device according to the present invention includes: two cables, each comprising two electrical conductors 161 and 162, configured to perform capacitance detection on respective capacitors C1 and C2 around cables 101 and 102; and a cable also comprising two electrical conductors 161 and 162. 1ref and 16 2ref A reference cable is provided, positioned where it will not be interfered with by any possible obstacles. Preferably, the reference cable is always under the same environmental conditions as cables 101 and 102, such as the same relative humidity. Each cable can be connected to a signal conditioner, and as... Figure 29 As shown, each cable 101, 102 is preferably connected to at least two signal conditioners to ensure safety redundancy.

[0312] exist Figure 25 In the examples, the signal conditioner is, for example, similar to Figure 26 or Figure 28 The signal conditioner in the system.

[0313] Figure 26 The example signal conditioner shown is connected to a cable comprising two electrical conductors, 161 and 162. The same voltage V... GBF It is applied to the two input terminals of the signal conditioner (operational amplifier). Therefore, the output voltage V... s With the capacitance C of the electrical conductor 161 (l,t) and C 162 The difference between (l,t) is proportional. If the capacitance C of the conductor is... 161 (l,t) and C 162 If (l,t) are equal, then V is equal to V if there are no obstacles near the cable. s The signal conditioner may also include at least one capacitor Cond, which allows the operating point of the signal conditioner to be fixed and the output voltage V to be adjusted. s .

[0314] The signal conditioner preferably includes a printed circuit with a capacitance of less than 4pF, or even better, less than 3pF.

[0315] The capacitance of the signal conditioner depends on the capacitance of the cable's conductors and the capacitance of the signal conditioner's printed circuitry. A relative humidity sensor is preferably used, which preferably acquires relative humidity values ​​periodically, for example at minute intervals. The capacitance per unit length of the conductor can then be estimated.

[0316] [Mathematical Expression 15]

[0317]

[0318] Where, ε air-RH％ ε is the dielectric constant of air as a function of relative humidity, ε0 ​​is the vacuum dielectric constant, and d ∞ For C(d) ∞ The distance ≈ 0, and r i Let i be the radius of the electrical conductor, i∈[1,2]. In this particular example, the cable consists of two electrical conductors.

[0319] Furthermore, electrical conductors can influence each other. If electrical conductors are raised to the same variable potential, they exert a repulsive force on each other. Therefore, the capacitance per unit length of an electrical conductor can be defined by the following formula:

[0320] [Mathematical Expression 16]

[0321]

[0322] Here, γ is a positive coefficient reflecting the repulsive force between electrical conductors. Reducing the capacitance per unit length can improve the capacitive sensitivity of the cable.

[0323] Finally, external environmental factors such as the walls, ground, and static components surrounding the cable can also affect the capacitance of the conductor. All these interactions can be transformed as follows:

[0324] [Mathematical Expression 17]

[0325]

[0326] Where M refers to the spatial location of the cable, and k i ext env ×d i Corresponding to the influence of a component that is part of the external environment on the cable, the distance d between the component and the cable is... i .

[0327] Then, the capacitance of the signal conditioner can be derived from the above:

[0328] [Mathematical Expression 18]

[0329]

[0330] Among them, C pr circuit is the capacitor of the printed circuit of the regulator, and Cond is the capacitor used to fix the operating point of the signal regulator.

[0331] exist Figure 25 In the example, preferably, the regulator includes a capacitor Ca. ctl Ca 1 ctl Ca 2 ctl It is used to fix the operating point of the regulator and adjust the output voltage of the regulator.

[0332] Generally, the signal conditioner is preferably configured to have high voltage response stability, for example, the voltage transmitted for detecting an obstacle at a distance of 30 cm drifts by less than 3% over time; and / or to be able to detect a person at a distance of less than or equal to 30 cm, with the capacitance change of the conductor being less than 1% for a distance of less than or equal to 30 cm; and / or to have a response time of approximately a few microseconds, preferably less than 50 microseconds.

[0333] The device according to the invention may include at least one encoder C for measuring the length l of a conductive cable portion and / or a relative humidity sensor H and / or at least one reference cable connected to a reference regulator. The reference cable is positioned where it will not be disturbed by any obstructions and is preferably always under the same environmental conditions as cables 101 and 102, such as the same relative humidity. Preferably, the device includes an encoder for each cable 101, 102, each encoder measuring the length l of the conductive cable portion to which it is connected. 101 l 102 .

[0334] The encoder can be of absolute type or incremental type.

[0335] The encoder is preferably an absolute encoder. In the case of an incremental encoder, the invention includes, as... Figure 23 The variant of element 91 shown employs an incremental encoder, and element 91 is capable of monitoring the function of the cable. Element 91 is, for example, a ring or an RFID tag.

[0336] The humidity sensor H and / or reference cable enable the measurement of relative humidity, verification and / or correction of capacitance drift, and reference values ​​that enable functions such as voltage comparison and / or correction devices.

[0337] exist Figure 25 In the example, in particular, the device includes a measuring device for the length l of the conductive cable portion. 101l 102 The system consists of two encoders C, a relative humidity sensor H, and a reference cable connected to the reference regulator.

[0338] Generally speaking, the device includes at least one reference cable connected to at least one reference regulator.

[0339] Each encoder C is preferably configured to comply with safety standards, such as NF EN ISO 13849-1 and / or IEC 61508, preferably covering at least low performance level PLA and / or low safety integrity level SIL1, and more preferably covering high performance level PLd or PLe and / or high safety integrity level SIL2 or SIL3.

[0340] The relative humidity sensor is preferably configured to comply with safety standards, such as NF EN ISO 13849-1 and / or IEC 61508, preferably covering at least the low performance level PLA and / or the low safety integrity level SIL1, and more preferably covering the high performance level PLd or PLe and / or the high safety integrity level SIL2 or SIL3.

[0341] like Figure 25 As shown, the device according to the invention preferably includes a safety control unit, which can be connected to one or more output relays and / or buses. If an obstacle is detected near at least one cable of the device, the output relay or bus can be triggered.

[0342] Figure 25 The device includes two output relays, R1 and R2. The output relays can be connected to control an actuator configured to cause at least one predetermined action upon detecting the approach of an obstacle. The output relays can be configured to act on the movement of a cable, and in particular, to stop movement upon detecting an obstacle. These output relays preferably conform to safety standards, such as EN ISO 13849-2.

[0343] Instead of output relays, or in addition to output relays, the safety control unit is connected to the safety bus and is preferably configured to comply with safety standards, such as ISO 13849-1 and / or IEC 61508, preferably covering at least the high performance class PLe and / or the high safety integrity class SIL3, respectively.

[0344] The safety control unit measures the voltage V at the output of the reference regulator. ref The voltage V1 at the output terminal of regulator 1 and the voltage V2 at the output terminal of regulator 2, voltage V ref Depending on the reference cable, voltage V1 depends on cable 101 and voltage V2 depends on cable 102.

[0345] The reference cable may have the same characteristics as at least one of cables 101 and 102. The reference cable has a fixed length L. ref Preferably, the length is 1m, 2m, or greater than 2m. (Refer to the cable length L.) ref Preferably, the length l is substantially equal to the average length l of the conductive cable portion of at least one of the cables 101 and 102 that performs the specific movement. 101 l 102 .

[0346] Advantageously, the fixed length L of the reference cable ref Between the minimum length value from the minimum of the conductive portions of cables 101 and 102 on the one hand and the maximum length value from the maximum of the conductive portions of cables 101 and 102 on the other hand (including the minimum length value and the maximum length value).

[0347] The safety control unit can compare the measured voltage with a detection threshold, which is preferably determined by the length L of cable 101 and / or cable 102, more preferably by the length l of the conductive cable portion. If at least one of voltage V1 and voltage V2 is greater than or equal to the detection threshold, at least one of output relays R1 and R2 can be triggered, and more preferably both relays can be triggered. The output relays can be triggered by a mechanically guided contact by the logic unit of the safety control unit, and the relays preferably employ positive logic.

[0348] The control unit is capable of detecting at least one, preferably all, voltage changes in a cable including at least one conductive cable section. The changes can be compared to a predetermined human fingerprint. For example, for a cable with an unwound length L of approximately 10 m and comprising two conductors, a human fingerprint can be detected as follows: when the person is 50 cm from the cable, ΔV is approximately 24 mV; when the person is 40 cm from the cable, ΔV is approximately 30 mV; when the person is 30 cm from the cable, ΔV is approximately 42 mV; when the person is 20 cm from the cable, ΔV is approximately 60 mV; and when the person is 10 cm from the cable, ΔV is approximately 93 mV.

[0349] Preferably, the safety control unit calculates the adjusted voltage V. 1 adjusted and V 2 adjusted The adjustment of these voltages V1 and V2 preferably depends on the relative humidity of the surrounding environment. Therefore, the voltage value V... 1 adjusted and V 2 adjusted Depending on the measurement performed by the relative humidity sensor H. Alternatively and / or additionally, the voltage value V is calculated relative to a reference conductor. 1 adjusted and V 2 adjusted For example, V 1 adjusted=V1±V ref and V 2 adjusted =V2±V ref .

[0350] The adjusted voltage may depend on the ambient relative humidity and / or predetermined voltage variations, such as those determined by determining the fingerprint and / or conductive cable length and / or reference cable.

[0351] The adjusted voltage can be compared with a detection threshold. If at least one of the adjusted voltages is greater than or equal to the detection threshold, at least one of the output relays R1 and R2, preferably both, is triggered.

[0352] Alternative ground and / or additional ground, if voltages V1, V2, V 1 adjusted and / or V 2 adjusted If the value is less than or equal to the predetermined value and / or greater than or equal to the predetermined value, output relays R1 and R2 can be triggered.

[0353] If the difference between voltage V1 and voltage V2 exceeds a predetermined value and / or if voltage V 1 adjusted With voltage V 2 adjusted If the difference between the voltages exceeds a predetermined value, at least one of the output relays R1 and R2 can be triggered. In practice, when there are no obstacles near cables 101 and 102, voltages V1 and V2 are preferably substantially equal. This predetermined value can depend on a predetermined distance between the obstacle and the cable.

[0354] Advantageously, the safety control unit has a redundant architecture. Preferably, the safety control unit is configured to have an HFT fault tolerance of 1. Advantageously, the safety control unit is configured to comply with safety standards, such as NF EN ISO 13849-1 and / or IEC 61508, preferably covering at least low performance level PLA and / or low safety integrity level SIL1, and more preferably covering high performance level PLd or PLe and / or high safety integrity level SIL2 or SIL3.

[0355] Figure 29 A schematic block diagram illustrating another example of the device according to the invention, wherein each of the two cables is connected to a corresponding signal conditioner, and the electrical conductors 161 and 162 of cables 101 and 102 are connected to each of the two conditioners connected to the cables.

[0356] Figure 27 This indicates an implementation that includes two independent and identical channels 35a and 35b, each of which includes a regulator connected to cables 101 and 102.

[0357] The two channels, 35a and 35b, can function in sequence.

[0358] Each regulator includes a connector 354 capable of supplying power to operational amplifiers 356 and 357, delivering a power supply voltage such as + / - 45V. Connector 354 can also control switches 351, 352, and 353. Advantageously, switch 353 can raise a portion of the cable, such as the cable shield, to the potential of the electrical conductor. This, in particular, prevents interference when the cable is used to power a load and / or for signal transmission.

[0359] A generator with two synchronous output channels preferably transmits the input signals V from both channels. GBF1 and V GBF2 .

[0360] Preferably, a Faraday barrier surrounds each of the two regulators to prevent any capacitive coupling. Generators GBF1 and GBF2 do not need to be surrounded by this barrier. Preferably, at least one oscillator transmits the input signal. The oscillator may be surrounded by the Faraday barrier. The oscillator may have a frequency of approximately 10 kHz. The Faraday barrier may be a box comprising a conductive inner wall and an outer wall electrically insulated from the inner wall, the conductive inner wall being raised to a predetermined variable potential of the electrical conductor by a voltage follower amplifier 357. The generator may be connected to the barrier via a BNC connector.

[0361] BNC plugs and shielded cables can be used to connect each cable 101, 102 to its signal conditioner, the core of the shielded cable connecting the signal conditioner to the cable, and the shielding, for example, by connecting to a voltage follower amplifier 357, raising the electrical conductors of the cables 101, 102 to a predetermined variable potential.

[0362] The printed circuitry of the support component of the signal conditioner can be fixed to the Faraday barrier. Preferably, the printed circuitry is not fixed to the barrier, thereby enabling easy replacement of the component when necessary, for example, if a component is defective.

[0363] Operational amplifiers, such as the AOP 445, can be mounted on 14-pin DIP (tulip) sockets. These operational amplifiers may be equipped with trimmers (e.g., 100kΩ) to adjust for offset voltage. The positive and negative power pins may each include capacitors for stabilizing the power supply voltage; for example, each positive and negative power pin may include a 10nF capacitor.

[0364] The switch can be an analog switch, such as a MAX14756 or DG411 switch. These switches can be installed in a 16-pin DIP (upright) socket.

[0365] like Figure 27The signal conditioner shown is particularly suitable for cables according to the invention, especially Figure 9N The cable shown or Figure 9P The cable shown. Preferably, a verification capable of validating the correct operation of the device is performed periodically, e.g., periodically, and / or whenever the device is restarted, by a safety control unit. Preferably, this verification includes comparing at least one of voltages V1 and V2 with a predetermined value. This predetermined value depends on, for example, C. a ctl Preferably, at least one check of the signal conditioner's operation is performed periodically and / or whenever the device is restarted.

[0366] For example, when switches 351 and 352 are open, the regulator is no longer in contact with the electrical conductor of the cable, and the output voltage V will be... s Compared with reference value V s ref Compare them.

[0367] Alternate sites and / or additional sites, such as Figure 28 As shown, the signal conditioner includes at least two control switches 359, each control switch 359 connected in series with a control capacitor 358 grounded. One of the control switches is connected to the positive power supply pin of the operational amplifier, and the other control switch is connected to the negative power supply pin of the operational amplifier. When switches 351 and 352 are open and control switch 359 is closed, the output voltage V measured at the output terminal of the operational amplifier can be obtained. s It is compared with a value that is known in advance and depends on the parameters of the control unit and the components of the signal conditioner.

[0368] If a fault is detected, at least one protective measure is implemented, such as an emergency stop device and / or a non-restart device.

[0369] When cables are connected to multiple regulators, the output voltage V measured at the output of the operational amplifier of each regulator can be compared during the calibration of the regulator's operation. s .

[0370] Alternative ground and / or additional ground can allow the output voltage V measured at the output of the operational amplifier to be... s With the voltage V from the reference regulator connected to the reference cable s ref Compare them.

[0371] Of course, the present invention is not limited to the embodiments already described.

[0372] Specifically, other information can be measured and / or stored, such as the relative speed of the cable to a person, animal, or object, or the detection error rate. The processing system can be configured to transmit information that is desired to be displayed on, for example, a control interface or alarm system.

[0373] Other sensors, such as visual sensors, especially those using image recognition methods, can provide supplementary information to the processing system, thereby allowing the determination of the nature or location of a person, animal, or object. The processing system can determine whether a person, animal, or object is approaching or moving away from one or more cables by analyzing information from the cable control system and / or from various sensors, particularly capacitive and / or optical sensors.

Claims

1. A method for detecting environmental changes near at least one conductive portion (10a) of a lifting, traction, or boundary cable, said environmental change relating to relative movement of at least one person, animal, or object relative to said conductive portion (10a), said method comprising the steps of: The detection indicates a change in capacitance of the moving conductive portion (10a), wherein the conductive portion (10a) rises to a predetermined variable potential, the cable (10) extends along at least a portion of a barrier (41) rising to the predetermined variable potential along its length, and / or the conductive portion (10a) is covered by an electrical insulator (12), the predetermined variable potential being an alternating current, and / or the conductive portion (10a) is in electrical contact with a conductive portion of an element (11) to which the cable (10) is attached, and / or the cable (10) includes at least one power supply conductor (15a, 15b, 15c) that supplies power to the element (11) moving through the cable, the at least one power supply conductor being surrounded by at least one barrier rising to the predetermined variable potential, the conductive portion (10a) being located outside the barrier.

2. The method according to claim 1, wherein, The cable is a lifting or traction cable, and the environmental changes are related to the person, animal or object approaching the conductive part (10a), thereby increasing the risk of the person, animal or object colliding with the conductive part (10a) and thus constituting a potential obstacle.

3. The method according to claim 1, wherein, The cable (10) extends over at least a portion of the barrier (41) that is raised to the predetermined variable potential along its length, wherein the barrier (41) extends at least partially around a system for guiding, driving and / or winding the cable.

4. The method according to claim 1, wherein, The cable (10) extends along at least a portion of the barrier (41) that rises to the predetermined variable potential along its length, wherein the barrier (41) is at least partially surrounded by a grounded shield (42).

5. The method according to claim 1, wherein, The conductive portion (10a) extends to the distal end of the cable, and / or the conductive portion (10a) comprises the entire cable (10), and / or the conductive portion (10a) extends over a length less than the length of the cable (10).

6. The method according to claim 1, wherein, The cable includes at least one core (15), and the conductive portion (10a) includes at least one electrical conductor (16) that is different from the core.

7. The method according to claim 6, wherein, The at least one electrical conductor includes one or more electrical conductors (16).

8. The method according to claim 7, wherein, The electrical conductor (16) is covered by an electrical insulator (12).

9. The method according to claim 1, wherein, The cable (10) includes at least one power supply conductor (15a, 15b, 15c) that supplies power to an element (11) moving through the cable. The at least one power supply conductor is surrounded by at least one barrier raised to the predetermined variable potential. The conductive portion (10a) is located outside the barrier. A grounding shield surrounds the barrier (41) raised to the predetermined variable potential, and the conductive portion (10a) is located outside the grounding shield.

10. The method according to claim 1, wherein, The cable (10) includes at least one core for withstanding traction, a detection conductor different from the core, and a signal transmission conductor surrounded by a grounded shield. The core is located around the shield and is raised to the potential of the detection conductor, which is located around the core and surrounded by an insulator.

11. The method according to claim 1, wherein, The cable includes at least two consecutive portions (61a, 61b, 61c) that are electrically insulated from each other, the at least two consecutive portions being subjected to a predetermined variable potential simultaneously or sequentially, thereby detecting the possible presence of the person, animal, or object near each of the at least two consecutive portions and being able to locate the person, animal, or object along the length of the cable, and / or wherein capacitance detection is performed on the one hand over the entire length of the cable (10) and on the other hand over at least a segment of the length of the cable, the location of which is known.

12. The method according to claim 1, wherein, The capacitance change is detected by measuring the current injected into the conductive portion (10a), and / or by unwinding the cable from the winding and / or drive system, by compensating for the change in electrical load caused by the modification of the unwound cable length, and / or by obtaining an amount representing the capacitance change of the conductive portion (10a) and an amount representing the movement of the cable, and / or by comparing the capacitance change over time and / or the trend of the movement of the cable with reference data.

13. The method of claim 12, comprising: Acquiring reference data by moving the person, animal, or object (20) relative to the cable in a predetermined manner, or by performing a predetermined movement of the cable (10) and / or the element (11) attached to the cable.

14. The method according to claim 1, comprising the following steps: If the person, animal or object (20) is detected to be near the conductive portion (10a) of the cable, at least one predetermined action is performed.

15. The method according to claim 1, wherein, The method is performed to detect the risk of collision between a person and at least some of the cables of a cable-driven parallel robot, or to detect a person approaching or avoiding boundary cables.

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