FR2584835A1 - Apparatus for controlling a nacelle elevator from the nacelle, with digital optical transmission of the control signals to the servomechanisms - Google Patents

Abstract

The apparatus comprises at least three hydraulic-action servomechanisms assigned to orienting and to lifting the arms of the nacelle carrying mast, and a control cabinet 35 situated in the nacelle 12. The cabinet sends out analog control signals. A transmitter 30 is associated with the cabinet 35 and is able to convert the control signals into digital signals with a servomechanism address. These signals are put into optical form by an interface 32 and addressed to a receiver means 40 via an optical fibre 20b. The receiver means restores the original control signals, echoes the digital signal received to the transmitter 30 via an optical link 20a, the transmitter 30 validating the digital signals whose echo is identical, and the receiver 40 addressing the reconstituted signals to the appropriate servomechanisms in response to the validation.

Description

"Control apparatus for a nacelle lift at
from the nacelle, with digital optical transmission
commands to the servo mechanisms "
The invention relates to a control apparatus for a nacelle lift comprising, on a motor vehicle chassis, a mast mounted with a vertical pivot on the chassis and composed of two articulated arms with toggle joint and capable of being raised on the horizontal, a first arm journalling horizontally on the pivot at its end away from the knee and the second arm carrying, at its end away from the knee, a turret with vertical axis carrying the nacelle orientable.

 Such nacelle elevators are used in particular for work on overhead electrical power lines, work which is carried out without voltage when it comes to medium or high voltage lines, and possibly under voltage for low voltage lines.

 The mast articulations are provided to define, from a stationing point of the lift vehicle, an action volume where the nacelle can evolve to allow its position to be adjusted relative to the organs where the operator must intervene Servomechanisms generally with hydraulic action act at least on the major joints of the mast, namely the orientation in the direction of the pivot, on at least 360, the lifting of the first arm relative to the pivot, and the lifting of the second arm compared to the first. The controls of these servo-mechanisms are grouped in a control box located in the nacelle, at the disposal of the operator, who is best able to assess the direction of the maneuvers to carry out to put the nacelle in the position of Of course, orders are generally relayed in a box placed on the chassis of the vehicle, for obvious safety reasons.

 These commands of the servo-mechanisms from the boxes are executed in response to control signals representative of a direction, an intensity of action or a state.

 As long as the nacelle lift is not designed to work under voltage higher than what is conventionally called low voltage, the connections between control boxes and servo-mechanisms can be ensured by conventional power lines, with excellent reliability, while electrical isolation and corresponding personnel protection are obtained by conventional solutions.

 But the problem is quite different when the nacelle lift is designed to work under medium or high voltage because, not only does the mast have to have an insulating section which provides satisfactory isolation security between the chassis of the vehicle on the ground and the nacelle where operators are located, but still each of the commands sent from the nacelle must be transmitted to the servo-mechanisms with a sufficient potential cutoff, and the reliability of the connections must be excellent, despite the potential cutoff, and in the presence of parasites generated by the presence of high or medium voltage and by the effects of variable capacity of the nacelle in displacement relative to the live parts.

 To ensure the reliability of the servo-mechanism controls, the invention provides control equipment for a nacelle lift comprising, on a motor vehicle chassis, a mast mounted with a vertical pivot on the chassis and composed of two articulated arms with toggle joint. and capable of being raised horizontally, a first arm journalling horizontally on the pivot at its end away from the knee lever and the second arm carrying, at its end away from the knee lever, a turret with vertical axis carrying the nacelle orientable, control apparatus comprising at least three servo-mechanisms with hydraulic action respectively assigned to the lifting of the first and second arms and to the rotation of the pivot, and responding to control signals representative of a direction and an intensity of action or of a state, signals formed at least in a control box operated by an operator placed in the nacelle, characterized in that said box is coupled a transmitter means capable of translating said analog control signals into digital signals composed of a series of words, each word comprising a servo-mechanism address, a mantissa of meaning and a characteristic of intensity or state, these digital signals being applied to a first optical link to a receiving means, the optical link comprising an electro-optical transducer at the start, a bundle of optical fiber and an opto-electric transducer at the arrival, the receiving means being capable of reconstituting from the digital signals in words, the original signals and direct them on the targeted servo-mechanisms, and being further able to return in active echo to the receiving means the digital signals in words received through a second optical link similar to the first and directed from the receiving means to sending means, the sending of each of the reconstituted analog signals to the targeted servomechanisms being subject to the identity of the digital signal in mo t corresponding with its echo.

 The electro-optical link ensures excellent potential decoupling between the transmitter and the receiver.

Transmitter and receiver are respectively substantially equipotential organs, on which relatively intense electric fields have practically no effect. The transmission of digital signals by optical links, combined with the control of the identity of the signals transmitted and received by means of the active echo signal return ensures, with excellent reliability, that no maneuver is executed without being ordered, while the transmission capacities (in band) of the electro-optical links make it possible to repeat each signal cyclically, so that a disturbed signal, not executed, will be followed by the same signal, undisturbed, which will be executed.

 Preferably, the nacelle elevator, for its use on high and medium voltage equipment will include a carrier insulating section in its second arm, and the optical fiber bundles, at least for the first and second optical links, pass along the neutral fiber. of this carrier insulating section.

 Preferably also, the transmitter and receiver means, with their associated electrical members, are respectively enclosed in enclosures forming electrical and magnetic shields, generally isolated from the electrical masses respectively of the nacelle and of the vehicle chassis, and joined respectively to these masses by a only electrical connection.

 These provisions make it possible to prevent parasites from disturbing the transmission and reception of digital signals (discharges by corona effect, electrical induction by high voltage, magnetic induction in the vicinity of currents, circulation currents in the masses).

 As in the conventional arrangements, the commands are relayed by a control box located on the vehicle, capable of directly attacking the servomechanisms. But this box is in connection with the receiver and therefore with the transmitter.

 In preferred arrangements, the receiver comprises a calculator means sensitive to sensor means associated with the articulations of the nacelle mast, and capable of determining the position of the nacelle relative to the vehicle, and prohibiting maneuvers outside a defined safety volume. . The vehicle has means for recording slope (along the chassis axis) and slope (transverse to the chassis), slope and slope involved in determining the safety volume. It will be understood that the chassis has limited capacities for resistance to overturning, and that the overturning torque induced by the departure of the nacelle relative to the vertical of the pivot must remain significantly less than the limiting overturning torque.

 It is possible to associate with the turret joint sensor means coupled to the transmitter means to transmit in digital form the turret orientation to the computer means via the receiver means and to intervene in the determination of the nacelle position.

 The turret can be fitted with telescopic, adjustable tool-holder arms. These arms are associated with sensors, connected to the transmitter means, which will digitally transmit the data from the sensors to the computer means via the receiver means, to define the safety volume of these arms.

The characteristics and advantages of the invention will become apparent from the description which follows by way of example, with reference to the accompanying drawings in which
FIG. 1 represents a gondola lift, of the type fitted with control equipment according to the invention
2 shows a side view, partially cut away of a section of insulating mast carrying the elevator according to Figure 1
Figure 3 is a section along the plane III-III of Figure 2
Figure 4 is an organizational diagram of a control apparatus according to the invention.

 According to Figure 1, a nacelle lifting device is mounted on a truck chassis 1. This device consists of a pivot 2, capable of being oriented in all directions by pivoting about a vertical axis. On this point is articulated, around a horizontal axis 2a, a first arm 3 of an articulated mast, liftable from the horizontal by a jack 4. At the end of the arm 3 opposite the pivot 2, is articulated by a toggle 5, with horizontal axis 5a, a second arm 8, 9, 10, which can be raised relative to the first arm 3 by a jack 6 acting on a compass 7. At the end of the second arm 8, 9, 10 is placed a turret-11 with vertical axis, which carries the nacelle 12.

 The chassis 1 of the truck is trimmed by a set of crutches 14, 14 ′, which define the angles of a lifting rectangle and an anchoring on the ground without the intermediary of the suspension.

 In what has just been described succinctly, the nacelle lift is not significantly distinguished from conventional nacelle lifters.

 The particularity basically lies in the structure of the second arm, which comprises, between two metal sections 8 and 10, which are articulated respectively on the first arm 3 by the toggle joint 5 and on the turret 11, a tubular carrying beam 9 which will be described in more detail with reference to Figures 2 and 3.

 This support beam 9 is insulating and constitutes a potential cutoff between the nacelle 12 and the vehicle 1 resting on the ground, with the first arm 3, the toggle joint 5 and the first section 8 of the second arm of the articulated mast.

 It will be noted that the nacelle 12 is articulated on the third section 8 of the second articulated arm, on the one hand, along the vertical axis of the turret 11, and on the other hand, along a horizontal axis 10a at the end of the third section 10 of the second articulated mast arm. This articulation is intended to keep the pivot axis of the turret 11 vertical despite the angles from which the first arm 3 and the second arm 8, 9, 10 of the articulated mast are raised. Maintaining the verticality of the turret axis 11 is ensured by sets of rods in articulated parallelograms which extend along the arms.

 In the elevator of the invention, the connecting rods of the second arm 8, 9, 10 are insulating rods.

 The orientation of the turret 11 around its vertical axis is controlled by a manual operation mechanism.

 In addition, the nacelle 12 is equipped with arms 13 capable of being extended longitudinally, maneuverable manually in extension and orientation, and provided to be equipped at their head 13a with tools for hydraulic operation, such as grabs, pliers or shears, the fluid hydraulic being brought to the nacelle by insulating pipes.

 We will talk later about hydraulic controls in general.

 Referring to Figures 2 and 3, the support beam 9 consists of a carrier tube 15 of epoxy resin armed with wicks of glass wound helically in reverse pitch. At a first end, the tube 15 is fitted into a tubular steel sleeve 16, glued in this sleeve 16. At this end, the epoxy resin tube 15 is closed by a plug 18 also made of epoxy resin, this plug being glued to the inside the tube 15. At the other end of the tube 15, a steel sleeve 17 is fitted and glued to the inside of the tube 15. Beyond the sleeve 17, the tube 15 is closed by a plug 19 in epoxy resin, bonded, similar to plug 18.

 Between the plugs 18 and 19, the tube 15 is stuffed with a polyurethane foam 21, with closed pores, formed in situ while avoiding any crack in the foam or in the joint between the foam 21 and the tube 15.

 In the neutral axis of the tube 15, which merges in the embodiment described with the geometric axis of the tube 15 of circular section, is extended a bundle 20 of six sheathed optical fibers, which is embedded without crack in the foam 21, crosses sealing the plugs 18 and 19, and protruding from the ends of the tube 15.

 These optical fibers are equipped at the end 6 with optical couplers for their connection to optoelectronic converter members.

 These optical fibers are intended to provide the link between an operating console located in the nacelle and governing all the control operations of the articulated mast arm, orientation of the turret 11, operation of the telescopic arms 13, an auxiliary operating console located on vehicle 1, and a central control unit for hydraulic controls located, with the hydraulic pump unit, on vehicle 1.

 It will be noted that there are two signal transmission lines, unidirectional, one for transmitting to the vehicle 1 from the nacelle 12 the teletransmission signals, the other for returning to the nacelle 12 the teletransmission signals from the vehicle 1.

 Under these conditions, only one pair of optical fibers in bundle 20 is used, the other four fibers remaining on standby, in order to repair damage to the fibers in service. The replacement of a fiber is carried out without difficulty, the nacelle elevator being in the rest position, by maneuvering the connectors at the two ends of the bundle 20, through inspection hatches arranged in the metal sections 8 and 10 of the second articulated mast arm.

 It will be understood that the socket 16 engages in the section 8 of the second arm, while the section 10 engages in the socket 17.

 We will now describe, with reference to Figure 4, the particular provisions of the invention.

 The switchgear parts which are located on the chassis are grouped together under the general reference 1, while the parts arranged in or accessible from the nacelle, are grouped together under the general reference 12. Between these two switchgear parts are arranged the optical connection fibers, which follow the arms 3 and 8, 9, 10 of the articulated mast. The optical connections comprise sections, connected by optical connectors 3q between the apparatuses 1 and the arm 3, 23 between the arm 3 and the second arm 8, 9, 10, 21 between this second arm and the turret (11 of the figure 1) and 22 between turret II and nacelle 12.

 Note that in the insulating section 9 of the second arm, the optical fibers 20a and 20b forming a pair are used, while the fibers 20c are on standby, to replace an accidentally damaged fiber.

 In the nacelle 12 is arranged a signal transmitter 30, enclosed in a shielding with high magnetic permeability of good conductive metal. This shielding is generally isolated from the ground of the nacelle at all points, except for a short connection 12a.

 The transmitter 30 includes a power supply unit 31, associated with a battery 34, which will be recharged from the general electrical circuits of the vehicle when the arms 3 and 8, 9, 10 are folded back into the road position, and which constitutes a source autonomous when the mast is unfolded.

 The power supply 31 is assigned to an electro-optical interface 32, in connection with an encoder / decoder microprocessor 33. The interface 32 includes an output 32a which emits light signals through the fiber 20k in response to electrical signals received from the encoder / decoder 33, and an input 32k which receives light signals via the fiber 20a, to form electrical signals intended for the encoder / decoder 33. The mode of formation and the role of the digital signals transmitted or received by the encoder / decoder 33.

 On the chassis of vehicle 1, a receiver 40 is arranged in a magnetic and electrical shielding similar to that of the transmitter 30. This shielding is also generally isolated from the ground of vehicle 1, and is only connected to the latter by a short connection. The receiver 40 includes a power supply 41, connected to the vehicle battery 44 and to an auxiliary group 48 through a so-called power and charging box 47, also capable of being connected to the sector by the input 47a when the elevator is in the garage.

 Like the transmitter 30, the receiver 40 includes an electro-optical interface 42, and an encoder / decoder 43.

The interface 42 has an output 42a which emits light signals to the fiber 20a in response to digital electrical signals received from the encoder / decoder 43, and an input 42b, connected to the optical fiber 20b to receive light signals and transform them in electrical digital signals to the encoder / decoder microprocessor 43.

 The receiver 40 also comprises a logic power control circuit 46, connected to the coder / decoder 43, adapted to control by its output 49 the hydraulic servos of the pivot 2, of the lifting cylinder 4 of the arm 3, and of the lifting cylinder 6 of the arm 8, 9, 10, as well as to trigger certain maneuvers such as starting the vehicle engine, the auxiliary group 48, hydraulic operation of the tools 13a at the end of the telescopic arms 13 (FIG. 1). The control circuit 46 also has two inputs, a and 9 connected to slope and slope detectors respectively.

 The logic control circuit 46 comprises a line of circuits per controlled function. When the function results in an all or nothing status command, the corresponding line is constituted by a simple amplification of power at logic level to attack a contactor for starting or stopping the controlled member. When the commanded function is a position control, like the hydraulic control of rotation of the pivot 2, lifting of the first arm 3 and lifting of the second arm 8, 9, 10, the line will respond to a sign, corresponding to the direction of position variation, dextrorotatory or levorotatory rotation for pivot 2, raising or lowering of arms 3 and 8, 9, 10; the line must also respond to an intensity, corresponding to the operating speed. The response of the line on output 49 in the direction of the respective servo will consist of operating signals from the servo valves.

The servo sends feedback signals back to the respective line. A person skilled in the art is capable of carrying out such enslavements, as soon as they are taught the main functional outlines.

 Furthermore, the feedback signals include position signals of the various servos. The logic control circuit comprises a calculating element which translates all of the position signals of the pivot and of the arms into position data of the turret II (FIG. 1) relative to the chassis 1. The calculating element also receives the data of slope and slope by inputs p and d, as well as data transmitted by the encoder / decoder microprocessor and representative of the orientation given to the nacelle 12 by the manual control of the turret 11, and of the orientation of the arms 13a by report relative to the turret. These various data, combined with data extracted from a table of the precalculated admissible safety limit forces, are compared to the position of the turret 11 relative to the chassis 1 in order to set in motion an alarm.

 We will now specify how the signals are exchanged between transmitter 30 and receiver 40. The encoder / decoder microprocessor 33 receives analog signals or status signals from the control box 35, via the shielded line 35c, and position sensors of the nacelle 12 relative to the turret 11, and of the tool-carrying arms 13 relative to the turret 11. The analog signals are digitized by the encoder / decoder 33, acting as an analog to digital converter. Each signal is stored in digital form with a sign at a particular memory location, with an address. The memory is read sequentially and the coder / decoder transmits to the interface 32 a cyclic sequence of words, each word corresponding to a particular signal and comprising an address, a sign mantissa, and an intensity characteristic, corresponding to the analog amplitude of the start or status signal.

 The interface 32 emits in response, on its output 32a an optical signal which is the image of the electrical signal received from the coder / decoder 33. The optical fiber 20b transmits the optical signal to the input 42k of the electro-optical interface 42, which in response sends to the coder / decoder 43 a digital cyclic electrical signal which is the reproduction of the signal transmitted by the coder / decoder 33 to the interface 32.

 The coder / decoder 43 stores in memory at locations determined by the address of the different words and simultaneously retransmits to the interface 42 an echo signal.

This signal is translated into a light signal on the output 42au, this signal being transmitted by the optical fiber 20a to the input 32k of the interface 32. This interface translates the light signal into an electrical signal intended for the coder / decoder 33. This coder / decoder performs an identity test between the received signal and the stored signals, and in the event of a positive response from the identity test, issues a validation word, translated into an optical signal by the interface 32, restored to an electrical signal by the interface 42, and transmitted to the coder / decoder microprocessor 43, which in response validates its recording in memory. The validated recording is used, each word being directed on the line corresponding to the address of the word, in the circuit of logic and power control 46. D
It will be noted that, in the example chosen, the cyclic sequence completed by the validation word lasts approximately one millisecond, which, taking into account the response speeds of the mechanical organs, ensures a real-time transmission of the commands from the nacelle 12 to the controlled mechanical parts.

 The directions of orientation of the nacelle 12 and of the telescopic arms 13, relative to the turret It could be given in analog form. But one can be satisfied with determining the orientations with a coarse resolution, of 30 for example, the indications then being O for an angle less than 15., +1 for the angles between 15. and 45, +2 for the angles included between 45 and 75- and +3 for angles between 75 and 90.

 The various commands are grouped, in the nacelle 12, in a shielded box 35 and connected by a screened line to the transmitter 30. The box comprises a button box 35a and a lever 35b with cross movement, similar to a handle with airplane broom.

 The button box has two columns of three buttons. In the left column, from bottom to top, the first button is assigned to rotate the pivot, the second to control the second arm, and the third to control the second arm. The right column is assigned to organ on / off commands, a pressure controlling the march, and a subsequent pressure controlling the stop. Starting from the bottom, the first button controls the pumping group of tools 13a arranged at the end of the telescopic arms 13, the second controls an auxiliary pumping group for the servos, used when the vehicle's engine is stopped. And the third button controls the starting and stopping of the vehicle's thermal engine, which drives the main servo pump.

 The elevator mast articulation servos are controlled by simultaneous action of the left column of the button box 35a and the lever 35h. To operate pivot 2, pressing the first button from the bottom determines the duration of the operation. The position of the lever 35b on the West-East line determines the direction of rotation (West left, East right) and the position amplitude of the lever determines the amplitude of the analog signal, which corresponds to a speed of rotation.

 The controls of the first and second arms are carried out in a similar manner, the pressure on the third or second button respectively determining the duration of maneuver, and the movement of the lever 35b on the North-South line determining the direction and speed of maneuver. It will be understood that the lever 35b is coupled to potentiometers to supply the analog signals.

 The box 45, associated with the receiver 40, has a structure similar to that of the box 35 associated with the transmitter 30. However, the commands issued by the box 35 have priority, except voluntary action on the box 45. The operator in the nacelle must be master of his maneuver. On the other hand, if the operator was unable to carry out a clearance maneuver, it is necessary that one can help him from the ground.

 Furthermore, the maneuvers controlled by the box 45, addressed to the coder / decoder 43, do not require a validation sent by the coder / decoder 33. It will be understood that the signals being produced directly by the coder / decoder 43 are not likely to be disrupted by optical transmission. In addition, since the box 45 essentially has a back-up role, it would not be appropriate for its action to be subject to the proper functioning of the optical transmission and of the transmitter 30.

 It will be appreciated that the digital transmission by optical fibers ensures a potential cut between the nacelle and the chassis which is extremely efficient, even when working on 90 KV lines. The reliability of the transmission, with validation subject to the identity of the signal echoing the original signal, is excellent. However, the reliability of all transmission equipment depends on the insensitivity to specific interference from work on high or medium voltage lines. Indeed, the reliability of a digital transmission is lost as soon as parasitic pulses coming from the outside are induced in the signal transmission channels with levels which reach half the amplitude of the useful signals, with a non-negligible occurrence. , or induced at a level much higher than the amplitude of the useful signals other than very exceptionally.

 However, high and medium voltage installations inevitably generate disturbances which have a very wide radio spectrum. The origin of these disturbances is found in the egrets or effects of crown which occur on metal parts subjected to very intense electric fields, in particular the parts which present projections with small radius of curvature. Other disturbances are created by the discharge of parasitic capacitances charged by the influence of intense electric fields, for example metallic parts in approach until contact. A third source of parasites is constituted by the magnetic field created by the intense currents which circulate in the conductors brought to high voltage.

 The influence of magnetic fields is greatly attenuated by the presence, around sensitive equipment, of shielding with high magnetic permeability.

The shielding in good conductive metal forms Faraday's cage for the electrical parasites which are propagated by air. Finally the general isolation of the shields of the transmitter 30 and the receiver 40, joined to local grounding by a single connection 12a, the short avoids the formation of loops between ground and shielding, loops which are very sensitive to currents vagrants.

 Of course, the invention is not limited to the examples described, and its scope is defined by the claims.

Claims (10)

 1) Control apparatus for a nacelle lift comprising, on a motor vehicle chassis (1), a mast mounted with a vertical pivot (2) on the chassis and composed of two articulated arms with toggle joint (5) and capable of being raised on the horizontal, a first arm (3) journalling horizontally on the pivot at its end separated from the kneepad (5) and the second arm (8, 9, 10) carrying1 at its end separated from the kneepad (5), a turret (11) with vertical axis carrying the nacelle (12), control apparatus comprising at least three servo-mechanisms with hydraulic action respectively assigned to the lifting of the first (3) and second (8, 9, 10) arms and to the rotation of the pivot (2), and responding to control signals representative of a direction and an intensity of action or of a state, signals formed at least in a control box (35) operated by an operator placed in the nacelle (12), characterized in that the box audit (35) is coupled with a m transmitting means (30) capable of translating said analog control signals into digital signals composed of a series of words, each word comprising a servo-mechanism address, a mantissa of meaning and a characteristic of intensity or state, these digital signals being applied to a first optical link to a receiving means (40), the optical link comprising an electro-optical transducer (32) at the start, a bundle of optical fiber (20 () and an optoelectric transducer (42k) at the start arrival, the receiving means (40) being able to reconstruct from the digital signals into words, the originating signals and direct them to the targeted servo-mechanisms, and being further able to return the digital signals to the active means in words received through a second optical link (42â, 20a, 32k) similar to the first and directed from the receiving means (40) to the sending means (30), the sending of each of the reconstituted analog signals to the targeted servo-mechanisms being subordinate to the identity of the digital signal in word corresponding with its echo.  2) Control apparatus for a nacelle lift intended for work on works on high or medium voltage, characterized in that the second arm (8, 9, 10) of the nacelle mast comprising a carrying insulating section (9) , the optical fiber bundles (20a, 20k, 20c) of at least the first and second optical links pass along the neutral fiber of said insulating carrier section.  3) Control apparatus according to claim 2, characterized in that said transmitter means comprises an autonomous power source (31, 34), with a battery (34) capable of recharging from the general circuits of the vehicle, the mast being folded back into rest position.  4) Control apparatus according to one of claims 2 and 3, characterized in that the transmitting means (30) and the receiving means (40), with their associated electrical members are enclosed respectively in enclosures forming electrical and magnetic shielding, generally enclosures electrically isolated from the electrical masses respectively of the nacelle (12) and of the vehicle chassis (1), and joined respectively to these masses by a single connection (12a, la).  5) Control apparatus according to any one of claims 1 to 4, characterized in that an auxiliary control box (45) is disposed on the chassis (1) of the vehicle and able to directly control the servomechanisms.  6) Control apparatus according to claim 5, characterized in that the control boxes (35, 45) comprise means for starting and stopping rotating groups (48) on the vehicle, respectively coupled to the transmitter (30 ) and the receiver (40) so that they insert specific words into the series of digital signals, in high and low interaction.  7) Control apparatus according to any one of claims 1 to 6, characterized in that the receiving means (40) comprises a calculating means (46) sensitive to sensor means associated with the articulations of the nacelle mast (12), and suitable determining the position of the nacelle (12) relative to the chassis (1) of the vehicle, and prohibiting maneuvers outside a predefined safety volume.  8) Control apparatus according to claim 7, characterized in that the vehicle has means for recording slope (n) and slope (d) of the chassis coupled to the calculating means (46), the slope and slope parameters involved in defining the security volume.  9) Control apparatus according to one of claims 7 and 8, characterized in that sensor means are associated with the turret joint (11) nacelle carrier (12), and coupled (33a) to the transmitter means (30 ) to transmit in digital form the turret orientation to the calculating means via the receiving means and to intervene in the determination of the nacelle position.  10) Control apparatus according to any one of claims 7 to 9, wherein the turret (11) is equipped with arms (13) adjustable telescopic tool holders, characterized in that sensors are associated with the orientations of the arms and coupled (33â) to the transmitter means (30) for digital transmission to the computer means (46) via the receiver means (40) and definition of the safety volume of said arms.