FR3160246A1 - Device and method for geotechnical surveying by proportional electrohydraulic control controlled by machine learning - Google Patents

Abstract

Geotechnical soil survey device, comprising a soil survey machine comprising, among other things, a drilling head, an actuator for advancing said drilling head, a main actuator for rotating said drilling head, and an electronic processing unit and sensors connected to the processing unit, which is designed to record survey parameters in real time; characterized in that the advance actuator and the motor for rotating the drilling head implement a proportional electrohydraulic autonomous system, and in that the processing unit is designed to acquire a geographical position of the survey machine, access a database containing soil characteristics based on the geographical position, and control the actuators using instructions determined by machine learning from the soil characteristics corresponding to the acquired geographical position and from the drilling parameters measured in real time. ABRIDGE FIGURE: [Fig. 1]

Description

Device and method for geotechnical surveying by proportional electrohydraulic control controlled by machine learning

The present invention relates to the field of geotechnical surveying.

BACKGROUND OF THE INVENTION

In the field of land use planning (e.g., buildings and public works (BTP), natural hazards), it is important to obtain an assessment of the mechanical condition of the soil. These soil condition assessments are generated, among other things, from data obtained by diagnostic tools (called logging tools in the industry) and make it possible to determine, in particular, useful data on the lithology of the layers to make the geotechnical model more reliable.

• une machine de sondage de sol, comprenant une tête de forage, un actionneur d’avance de ladite tête de forage et une motorisation principale d’entrainement en rotation de ladite tête de forage ;
• une unité électronique de traitement et des capteurs reliés à l’unité de traitement qui est agencée pour enregistrer des paramètres de sondage en temps réel.

One of these tools is a geotechnical survey device, comprising:

• a ground drilling machine, comprising a drilling head, an actuator for advancing said drilling head and a main motor for driving said drilling head in rotation;
• an electronic processing unit and sensors connected to the processing unit which is arranged to record survey parameters in real time.

The drilling machine is equipped with a manual control system that allows an operator to control, among other things, the advance and rotation of the drilling head. The control of the drilling machine, in particular for the advance and rotation of the drilling head, is carried out manually by the operator. It is also known to manually calibrate the drilling machine before use, based on the operator's knowledge of the nature of the soil, in order to be able to use the measurement of the drilling parameters in the soil composition assessment.

However, human intervention on the settings or controls of the survey machine can have an impact on the value of the survey parameters which are recorded to determine the soil characteristics (nature and mechanics). As a result, surveys carried out by several operators do not allow for reliable soil characteristics to be obtained in the sense that they will not necessarily be comparable.

SUBJECT OF THE INVENTION

The invention aims in particular to reliably carry out calibrated measurements of drilling parameters in order to obtain, in a homogeneous and comparable manner, the composition of the soils by drilling.

• une machine de sondage de sol, comprenant une tête de forage, un actionneur d’avance de ladite tête de forage et une motorisation principale d’entrainement en rotation de ladite tête de forage ;
• une unité électronique de traitement et des capteurs reliés à l’unité électronique de traitement qui est agencée pour enregistrer des paramètres de forage en temps réel.

For this purpose, according to the invention, a geotechnical survey device is provided, comprising:

• a ground drilling machine, comprising a drilling head, an actuator for advancing said drilling head and a main motor for driving said drilling head in rotation;
• an electronic processing unit and sensors connected to the electronic processing unit which is arranged to record drilling parameters in real time.

• acquérir une position géographique de la machine de forage,
• accéder à la base de données contenant des caractéristiques de sol en fonction de la position géographique,
• commander l’actionneur et la motorisation principale à partir d’instructions de commande issues d’un apprentissage automatique, déterminées à partir des caractéristiques de sol correspondant à la position géographique acquise, et des paramètres de forage mesurés en temps réel.

The feed actuator and the main motor for driving the drilling head in rotation implement a proportional electrohydraulic autonomous system and in that the processing unit is arranged to:

• acquire a geographical position of the drilling machine,
• access the database containing soil characteristics based on geographic position,
• control the actuator and the main motorization from control instructions resulting from automatic learning, determined from the ground characteristics corresponding to the acquired geographical position, and the drilling parameters measured in real time.

The advance and rotation of the drilling head are controlled automatically and proportionally, depending on the geographical position of the drilling, soil characteristics determined according to the geographical position and pre-calibrated drilling parameters.

• l’unité électronique de traitement est agencée pour commander la machine de sondage de manière à maintenir constante d’une part une contrainte axiale appliquée à la tête de forage lorsque l’extrémité de la tête de forage est en contact avec le sol en cours de forage et d’autre part une vitesse de rotation de la tête de forage ;
• la base de données est hébergée dans une mémoire de l’unité électronique de traitement ;
• l’unité électronique de traitement possède en mémoire, pour chaque type de milieu foré, un mode de commande de la machine de sondage, ces modes de commande se caractérisant par des instructions de forage et l’unité électronique de traitement est agencée pour détecter un changement de milieu en fonction d’au moins un seuil prédéfini pour au moins un paramètre de forage ;
• l’unité électronique de traitement est agencée pour changer de mode de commande de manière autonome ;
• l’unité électronique de traitement comprend une interface de commande agencée pour permettre à un opérateur de commander un changement de mode de commande ;
• l’unité électronique de traitement est reliée à un système de géolocalisation pour fournir la position géographique de la machine de sondage ;
• l’unité électronique de traitement comprend une interface de commande agencée pour permettre à un opérateur de saisir la position géographique de la machine de sondage ;
• une motorisation hydraulique secondaire est agencée pour entrainer en rotation la tête de forage, un capteur de pression est agencé pour détecter un seuil de pression dans la motorisation principale d’entrainement en rotation de la tête de forage et un commutateur est associé au capteur de pression pour activer la motorisation secondaire afin de conserver une vitesse de rotation constante en cas d’atteinte du seuil de pression dans la motorisation principale.

Depending on optional features, used individually or in whole or in part in combination:

• the electronic processing unit is arranged to control the drilling machine so as to maintain constant on the one hand an axial stress applied to the drilling head when the end of the drilling head is in contact with the ground during drilling and on the other hand a rotation speed of the drilling head;
• the database is hosted in a memory of the electronic processing unit;
• the electronic processing unit has in memory, for each type of drilled medium, a control mode of the drilling machine, these control modes being characterized by drilling instructions and the electronic processing unit is arranged to detect a change of medium as a function of at least one predefined threshold for at least one drilling parameter;
• the electronic processing unit is arranged to change control mode autonomously;
• the electronic processing unit comprises a control interface arranged to allow an operator to command a change of control mode;
• the electronic processing unit is connected to a geolocation system to provide the geographical position of the survey machine;
• the electronic processing unit comprises a control interface arranged to allow an operator to input the geographical position of the survey machine;
• a secondary hydraulic motor is arranged to rotate the drilling head, a pressure sensor is arranged to detect a pressure threshold in the main motor for rotating the drilling head and a switch is associated with the pressure sensor to activate the secondary motor in order to maintain a constant rotation speed if the pressure threshold is reached in the main motor.

• effectuer de manière autonome en électrohydraulique proportionnel une avance limitée et une rotation régulée d’une tête de forage ;
• détecter et adapter des paramètres de forage en temps réel, par apprentissage automatique, durant le sondage.

The invention also relates to a geotechnical survey method comprising the steps:

• autonomously carry out, using proportional electrohydraulics, a limited advance and a regulated rotation of a drilling head;
• detect and adapt drilling parameters in real time, using machine learning, during drilling.

The advance and rotation of the drilling head are controlled proportionally according to a geographical position of the drilling, soil characteristics determined according to the geographical position and drilling parameters.

Other characteristics and advantages of the invention will emerge upon reading the following description of a particular and non-limiting embodiment of the invention.

Reference will be made to the attached drawings, including:

FIG. 1 there FIG. 1 is a schematic elevation view of a survey machine used in the device according to the invention;

FIG. 2 there FIG. 2 is a diagram illustrating the overall operation of the geotechnical survey device according to the invention;

FIG. 3 there FIG. 3 is a flowchart showing an implementation of the geotechnical survey method according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

The invention relates to a geotechnical survey device which comprises in particular a survey machine 1 and an electronic processing and control unit 100.

The drilling machine 1 comprises a mobile frame 11, a lifting frame 12 mounted to pivot about a horizontal axis on the frame 11, and a drilling head 14 which slides on the lifting frame 12 and which drives a drill string 13. This drill string 13 rotates about an axis of rotation coinciding with a central axis of the drill string 13.

The survey machine 1 also includes several hydraulic actuators.

An actuator 15.1 allows the drilling head 14 and therefore the drill string 13 to move forward or backward. This actuator 15.1 incorporates a first hydraulic circuit 16.1 having a geared motor or a cylinder 22.1 capable of converting the pressure in said first circuit 16.1 into a translational movement of the drill string 13. The hydraulic pressure in the first circuit 16.1 is regulated by a proportional electrohydraulic distributor 17.1 belonging to the first circuit 16.1. It is understood that the pressure within the first hydraulic circuit 16.1 conditions the speed of advance of the drilling head 14. By controlling the proportional electrohydraulic distributor 17.1 of the first circuit 16.1, it is therefore possible to precisely and analogically control the pressure within said first circuit 16.1, and therefore the speed of advance of the drilling head 14.

A main motor 15.2, independent of the actuator 15.1, enables the rotational drive of the drilling head 14. This main motor 15.2 incorporates a second hydraulic circuit 16.2 having a hydraulic motor 22.2 capable of converting the flow of fluid circulating within said second circuit 16.2 into a rotational movement of the drilling head. The flow circulating in this second circuit 16.2 is regulated by a proportional electrohydraulic flow regulator 17.2. By controlling this proportional electrohydraulic flow regulator 17.2, it is possible to precisely and analogically control the flow of fluid within the second circuit 16.2, and therefore precisely control the rotational speed of the drilling head 14.

An auxiliary motor 15.3 is installed within the device in parallel with the main motor 15.2. The auxiliary motor 15.3 is arranged to rotate the drilling head 14. This auxiliary motor 15.3 incorporates a hydraulic motor 22.3 capable of converting the flow of fluid circulating within said second circuit 16.2 into a rotational movement of the drilling head. The hydraulic circuit of the auxiliary motor 15.3 is the same as that of the main motor 15.2. This auxiliary motor 15.3 is actuated by a switch 18 when an overpressure is detected in the second hydraulic circuit 16.2. The auxiliary motor 15.3 does not operate during normal operation of the device. The actuation of this auxiliary motor 15.3 allows the drilling head 14 to maintain a constant rotation speed in the event of a pressure limit threshold being reached in the main motor 15.2.

• la longueur de pénétration (encodeur) ;
• la pression de poussée (capteur de pression) ;
• la pression de retenue (capteur de pression) ;
• la pression du fluide de forage chargé du refroidissement de la tête de forage et de l’évacuation des débris de forage (capteur de pression) ;
• le débit d’injection du fluide de forage (débitmètre) ;
• la vitesse de rotation de la tête de forage (débitmètre et tachymètre) ;
• le couple de rotation (capteur de pression) ;
• l’énergie réfléchie(accéléromètre).

The processing unit 100 comprises at least one processor, a memory containing programs executable by the processor, a connection interface with the drilling machine 1 to send it control signals and receive measurement signals from sensors installed in the drilling machine 1, a man-machine interface to allow an operator to communicate with the processing unit 100, an electronic card for precise control of the electrohydraulic functions, a telecommunications card and a receiver of geolocation satellite signals 19. The interface of the processing unit 100 is thus connected to a set of sensors 20 allowing the acquisition of measurement parameters, in particular: pressure sensors, an accelerometer, a flow meter and an encoder. Among these parameters acquired by the processing unit 100, we find:

• the penetration length (encoder);
• thrust pressure (pressure sensor);
• the holding pressure (pressure sensor);
• the pressure of the drilling fluid responsible for cooling the drilling head and evacuating drilling debris (pressure sensor);
• the drilling fluid injection rate (flow meter);
• the rotation speed of the drilling head (flow meter and tachometer);
• the torque (pressure sensor);
• reflected energy (accelerometer).

All of the measured data is recorded locally on a physical storage system 21 connected to the processing unit 100.

The processing unit 100 is programmed to acquire as input data the geolocation data coming from the geolocation satellite signal receiver 19 allowing said processing unit 100 to know its position.

• récupérer depuis ladite base de données, les caractéristiques de sols correspondant à la position géographique correspondant aux données de géolocalisation ;
• faire mémoriser dans la base de données l’ensemble des données mesurées et la position géographique correspondante pour qu’elles y soient archivées.

The processing unit 100 is also programmed to connect via the telecommunications card to a network and to access the contents of an external geotechnical database. The database groups together a set of archival geotechnical data. The database also contains soil composition characteristics listed according to the geographical position and all the data previously measured by the geotechnical survey device. During communication between the processing unit and the database, the processing unit 100 is programmed to:

• retrieve from said database the soil characteristics corresponding to the geographic position corresponding to the geolocation data;
• have all measured data and the corresponding geographical position stored in the database so that they can be archived there.

• acquérir une position géographique de la machine de forage 1,
• accéder à la base de données contenant des caractéristiques de sol en fonction de la position géographique,
• commander l’actionneur 15.1 et la motorisation principale 15.2 à partir d’instructions de commande déterminées par apprentissage automatique (oumachine learning) à partir des caractéristiques de sol correspondant à la position géographique acquise, et des paramètres de forage mesurés en temps réel (ceci est présenté plus en détail plus loin).

The processing unit 100 is programmed to:

• acquire a geographical position of the drilling machine 1,
• access the database containing soil characteristics based on geographic position,
• control the actuator 15.1 and the main motor 15.2 from control instructions determined by machine learning from the ground characteristics corresponding to the acquired geographical position, and the drilling parameters measured in real time (this is presented in more detail later).

In order to measure as precisely as possible the reaction of the drilled medium (i.e. the ground) during drilling, and thus determine its characteristics, the value of the pressure applied to the drilling head 14 against the ground is kept constant by the processing unit 100. The processing unit 100 controls the actuator 15.1 for advancing the drilling head 14 so as to apply a constant axial stress during drilling, that is to say when the tool of the drill string 13 is in contact with the ground during drilling.

Preferably, the processing unit 100 has in memory several control modes for the survey machine 1, each corresponding to a type of medium to be surveyed (for example, limestone soil, limestone soil with marl, granite soil, etc. or more roughly hard soil, soft soil, etc.). Each control mode for the survey machine 1 includes instructions to be executed by the different actuators of the survey machine 1 to acquire the measured data as efficiently as possible.

Each control mode corresponds to a calibration adapted to the medium concerned. This calibration makes it possible in particular to limit nominal values of advancement speed and regulate rotation speeds and to adjust the advancement speed and the rotation speed of the drilling head 14 between minimum and maximum values corresponding to the medium. The processing unit 100 is programmed to detect a change of medium during drilling, depending on the passage of at least one predefined threshold for at least one drilling parameter. The processing unit therefore changes operating mode autonomously, that is to say without intervention from an operator.

The control of the maximum feed speed and the maximum rotation speed of the drilling head 14 is carried out analogically and is ensured by the proportional electrohydraulic regulator and the proportional electrohydraulic distributor, allowing to improve the quality and comparability of the drilling tests.

Externally to the survey device, at the server hosting the database, the measured parameters are used by a statistical learning system operating by automatic learning (commonly called machine learning ). This system allows, by learning, to deduce the average behavior of the soils according to the location. This learning is based on the data acquired on different previously surveyed sites, and on engineering conclusions which result from these measurements, that is to say a human exploitation phase whose conclusions are provided to the learning system in a form and in a computer format usable by the latter. With this database and the average parameters obtained by automatic learning, the survey device will be able to be configured and calibrated for a given location. All the information in the database is processed via automatic learning then transmitted to the exploitation phase to improve the relevance of the analysis, and to the processing unit 100 to improve the calibration of the survey machine 1.

In order to enable the processing unit 100 to determine the effectiveness of the calibration of the drilling machine for a drilling condition, it is necessary for the type of drilling head tools 14 to be acquired and recorded by said processing unit 100 and for the drilling tool to be retained for the entire duration of the drilling. This acquisition can be manual (recording of a code associated with the drilling head, reading of a bar code) or automatic (the drilling head is provided with an NFC circuit, for example RFID, which can be read by a reader of the machine when the head is in place on the drill string).

In order to take into account, when exploiting the results of a survey, the influence of the drilling machine 1, a systematic recording of the parameters and characteristics of the drilling machine 1 is provided. The manual adjustment of certain parameters of the drilling machine 1 must be set to predetermined values. In order to take into account the influence of the drilling machine 1 on the results obtained, it is also provided to operate the various components of the drilling machine 1, significantly below their maximum capacity to guarantee the success and quality of the measurement. It is preferably provided that the drilling machine 1 can carry out hammering when drilling hard media: it is then necessary that the use of such hammering is recorded to be taken into account when exploiting the drilling results.

In order to minimize the operator's influence on the results, it is therefore important that the operator records every action he performs, such as hammering, or the flow rate and pressure when using a mud pump, for example. The operator has an influence because he can manually activate the auxiliary motor and therefore influence the pressure and injection flow rate at the output of the drive motor. Controlling the rotation speed electrohydraulically will relieve the operator of the control and influence he may have at this level. It will also allow the activation of the secondary motor to be automatically recorded and noted.

It is intended that the measurements are acquired and recorded by the processing unit 100 with a frequency allowing a resolution of at least one measurement per centimeter, even when the drilling progress speed is maximum.

The measuring unit 100 is arranged to perform data acquisition by obeying commands such as: Start measurements; Send measurements; Pause measurements; Resume measurements; Stop measurements.

All measured data is then transmitted to the physical storage system 21 connected to the processing unit, before being sent to the database.

Of course, the invention is not limited to the embodiment described but encompasses any variant falling within the scope of the invention as defined by the claims.

In particular, although the change of operating mode depending on the drilled environment is ensured autonomously by the processing unit, the case is envisaged where the device comprises a control interface arranged to allow an operator to manually control a change of operating mode.

Concerning the acquisition of geolocation data, although the device in the described embodiment has a receiver of geolocation satellite signals allowing the automatic acquisition of geolocation, the case is envisaged where the device comprises a control interface arranged to allow an operator to enter the geographical position of the machine.

Although the survey described in the description is purely destructive, it is envisaged that the survey device will also be used to take samples in a coring, augering, and pressuremeter measurement operation requiring the use of a drill bit suitable for this purpose.

The database may contain only ground characteristics depending on the location: the processing unit is arranged to develop the machine commands from the ground characteristics corresponding to its location. Alternatively, the database may also contain machine commands that have been determined from the ground characteristics corresponding to the location: the processing unit is then arranged to directly exploit the commands from the database.

Machine learning is preferably performed on an external server, between the database and the processing unit. Machine learning is therefore not performed in the processing unit in the envisaged embodiment. Machine learning is arranged to obtain the configuration parameters which are transmitted to the processing unit which will then configure the survey machine. The configuration of the actuator/motor controls is performed after the instructions have been determined by machine learning.

The electronic components of the device are expected to meet outdoor measurement conditions, for example through tropicalization of the components.

Claims (10)

Geotechnical survey device, comprising:

• a ground drilling machine (1), comprising a drilling head (14), an actuator (15.1) for advancing said drilling head and a main motor (15.2) for driving said drilling head (14) in rotation;
• an electronic processing unit (100) and sensors (20) connected to the electronic processing unit (100) which is arranged to record drilling parameters in real time;

characterized in that the feed actuator (15.1) and the main motor (15.2) for driving the drilling head (14) in rotation implement an autonomous proportional electrohydraulic system and in that the processing unit is arranged to:

• acquire a geographical position of the drilling machine,
• access the database containing soil characteristics based on geographic position,
• control the actuator and the main motorization from control instructions resulting from automatic learning, determined from the ground characteristics corresponding to the acquired geographical position, and the drilling parameters measured in real time.

Device according to claim 1, in which the electronic processing unit (100) is arranged to control the drilling machine (1) so as to maintain constant on the one hand an axial stress applied to the drilling head (14) when the end of the drilling head (14) is in contact with the ground during drilling and on the other hand a rotation speed of the drilling head. Device according to one of the preceding claims, in which the database is hosted in a memory of the electronic processing unit (100). Device according to one of the preceding claims, the electronic processing unit (100) of which has in memory, for each type of drilled medium, a control mode for the drilling machine (1), these control modes being characterized by drilling instructions and the electronic processing unit (100) is arranged to detect a change of medium as a function of at least one predefined threshold for at least one drilling parameter. Device according to claim 4, in which the electronic processing unit (100) is arranged to change control mode autonomously. Device according to claim 4, wherein the electronic processing unit (100) comprises a control interface arranged to allow an operator to command a change of control mode. Device according to one of the preceding claims, in which the electronic processing unit (100) is connected to a geolocation system (19) to provide the geographical position of the survey machine (1). Device according to one of claims 1 to 6, in which the electronic processing unit (100) comprises a control interface arranged to allow an operator to enter the geographical position of the drilling machine (1). Device according to claim 1, comprising a secondary hydraulic motor (15.3) arranged to rotate the drilling head (14), a pressure sensor arranged to detect a pressure threshold in the main motor for rotating the drilling head (14), and a switch (18) associated with the pressure sensor to activate the secondary motor (15.3) in order to maintain a constant rotation speed if the pressure threshold is reached in the main motor (15.2). Geotechnical survey process comprising the steps:

• autonomously carry out, using proportional electrohydraulics, a limited advance and a regulated rotation of a drilling head;
• detect and adapt drilling parameters in real time, using machine learning, during drilling;

characterized in that the advance and rotation of the drilling head (14) are controlled proportionally as a function of a geographical position of the borehole, soil characteristics determined as a function of the geographical position and borehole parameters.