Abstract: Systems and methods are disclosed that provide highly accurate and controllable measurements of rock formation properties in a wellbore. The systems and methods utilize a prescribed input signal to mechanically perturb a drill string in contact with a rock formation in order to elicit a mechanical response. Based on the input signal and the mechanical response, a transfer function is computed and analyzed, wherein the analysis uses estimates of the drill string resonances to identify rock formation resonances, which are used, in turn, to determine the rock formation properties.

Abstract: A method for selecting drilling parameters for drilling a borehole penetrating the earth with a drill string includes: varying a frequency of an excitation force applied to the drill string using an excitation device controlled by a drill string controller and measuring vibration-related amplitudes of the drill string due to the applied excitation force using a vibration sensor to provide amplitude measurements. The method further includes determining one or more modal properties comprising one or more eigenfrequencies of the drill string using the amplitude measurements and selecting drilling parameters that apply an excitation force at a frequency that avoids a selected range of frequencies that bound the one or more eigenfrequencies.

Abstract: Provided is a method for selecting one of a plurality of convergence paths that may be drilled by a bottom hole assembly (BHA) comprising identifying, by a computer system, a plurality of geometric convergence paths, wherein each of the geometric convergence paths provides a convergence solution from a defined bottom hole assembly (BHA) location to a target drilling path of a well plan. An offset distance is calculated for drilling by the BHA each of the geometric convergence paths connecting the BHA location to the target drilling path. A drill path curvature associated with drilling each of the geometric convergence paths by the BHA is determined by the computer system. A time required for drilling each of the geometric convergence paths by the BHA is determined by the computer system.

Abstract: A method, comprising acquiring annular pressure data from a wellbore where the annular pressure data is acquired over a time interval and at least a portion of the annular pressure data is acquired during a pumps-off period. At least first and second values are identified from the annular pressure data and the variation between the first and second values are compared to a first threshold. Drilling equipment is operated based on the comparison with the first threshold.

Abstract: Systems, methods, and devices for evaluation of an earth formation intersected by a borehole using a logging tool. Tools include sensor assemblies with permanent magnets mounted at a first radial distance from an axis of rotation of the sensor assembly, as well as receiver sensors. The sensor assembly is configured to generate an alternating current in a volume of interest of the formation surrounding the borehole with a time varying magnetic field in the volume produced by rotating the sensor assembly about the axis of rotation. Methods include making EM signal measurements or magnetic field measurements with receiver sensors responsive to the alternating current and estimating at least a formation property of the volume using the measurements.

Abstract: The present disclosure generally relates to a real-time synthetic logging method for optimizing one or more operations in a well. The method generally includes receiving measurements of one or more parameters in real time while performing operations in the well, the measurements being captured without using tools that include active nuclear sources. The method further includes providing the measurements as input to a machine learning algorithm (MLA) that is trained using historical or training well data. The method further includes generating, using the MLA and based on the measurements, a synthetic mechanical property log of the well. The method further includes generating, based on the synthetic mechanical property log, optimized parameters for at least one operation selected from the following list: drilling the well in real-time; steering the well in real-time; and stimulating a reservoir in real-time.

Abstract: A method for monitoring performance of an electric submersible pump. The method includes receiving data indicating a plurality of observable parameters from one or more sensors, generating a reduced set of components representative of at least some of the observable parameters and the reduced set having a dimensionality less than the plurality of observable parameters, identifying one or more components of the reduced set that captures a total variance of the plurality of observable parameters above a predetermined threshold, constructing at least one manifold of normal operation of the electric submersible pump in a reduced component space, receiving additional data from the sensors, transforming the additional data into the identified components establishing an electric submersible pump performance, and detecting whether a deviation of the electric submersible pump performance from a normal mode of operation of the electric submersible pump exceeds a predetermined threshold.

Abstract: A method for drilling a well includes prescribing a drill recipe with a drill analysis engine based on a field-specific model. The drill recipe identifies prescribed segments, mud flow parameters, and drill parameters. Each prescribed segment of the prescribed segments includes a start depth. The method further includes initiating drilling of the well based on the drill recipe; receiving a drill log in narrative text format; detecting a drill event inconsistent with the drill recipe by analyzing the drill log with a log analysis engine; prescribing an adjusted drill recipe with the drill analysis engine based on the field-specific model in response to the drill event, the adjusted drill recipe including adjusted prescribed segments; and drilling the well based on the adjusted drill recipe.

Abstract: Tools and method for automatically controlling torque when making-up and/or breaking-down threaded connections between downhole assets such as drill pipe, drill collars, and BAH components. An iron roughneck may be controlled by, for instance, automatically monitoring and adjusting the fluid pressure of cylinders that ultimately provide the torque to the downhole assets. The torque may further be automatically controlled by automatically identifying the downhole assets and selecting a corresponding torque profile or target torque. Clamping force may also be controlled, and is optionally proportional to the target torque.

Abstract: A control system for controlling stick-slip oscillations in a drilling system is disclosed. The control system includes a processor and a memory communicatively coupled to the processor with computer program instructions stored therein. The instructions are configured to, when executed by the processor, cause the processor to receive a communication including a value of a drilling system parameter, determine based on the value of the drilling system parameter, a value for a torque to be applied to a drill string to reduce the effect of stick-slip oscillations, and transmit to a drive system the value for the torque to be applied by the drive system. The value for the torque to be applied by the drive system is determined by solving a set of linear matrix inequalities including a disturbance minimization linear matrix inequality, a first magnitude constraint linear matrix inequality, and a second magnitude constraint linear matrix inequality.

Abstract: A method may include providing a drill string positioned in a wellbore including a measurement tool. The method may include taking a measurement with the measurement tool at a first location; coupling a pipe stand including a first selected number of tubular segments to the drill string, the first selected number being two or more; lowering or advancing the drill string into the wellbore the length of the pipe stand; taking a measurement with the measurement tool at a second location; raising the drill string the length of a tubular segment; removing a second selected number of tubular segments from the drill string; taking a measurement with the measurement tool at a third location; raising the drill string the length of the first selected number of tubular segments; removing the first selected number of tubular segments; and taking a measurement with the measurement tool at a fourth location.

Abstract: A method of drilling a well within a target stratum. The method can include drilling based upon a target window created from previously collected and/or extrapolated data. Data is collected while drilling and the target window can be adjusted “on the fly” as well as updating and correcting previously collected data. The method can be repeated to ensure optimal drilling efficiency and minimal down time while drilling.

Abstract: Embodiments of systems and methods to control directional drilling in borehole drilling for hydrocarbon wells are disclosed. An actual toolface orientation measurement value and an actual downhole torque on bit (DTOB) or actual downhole weight on bit (DWOB) measurement value for a drill string positioned in a borehole are determined. Responsive to a comparison of target measurement values and actual measurement values, error values are determined. A control command for one or more of a top drive, a drawworks, and a mud pump responsive to the DTOB or DWOB error value and the toolface orientation error value is determined. Additionally, one or more of the top drive, the drawworks, and the mud pump are operated responsive to the control command thereby to correct a toolface orientation of the drill string.

Abstract: Methods and control systems for optimizing production of a hydrocarbon well with a local controller in communication with a supervisory control and data acquisition (SCADA) system are disclosed. The presently disclosed methods may include calculating, at the local controller, optimal targets for one or more well parameters using measured values associated with operation of the hydrocarbon well; obtaining, at the local controller, a model that comprises a relationship between an operation of a gas injection choke and an operation of a production choke with the one or more well parameters based on the measurement values and received model parameters from the SCADA system; determining, at the local controller, operating set points based on the model for control of at least one of the production choke and the gas injection choke; and operating at least one of the production choke and the gas injection choke for optimized production.

Abstract: Mud pulse telemetry. The various embodiments are directed to methods and systems of encoding data in a mud pulse telemetry system, where at least a portion of the data is encoded the time between pressure transitions. Moreover, the various embodiments are directed to detection methods and systems that detect the pressure transitions at the surface.

Abstract: A drilling system and associated systems and methods for monitoring, controlling, and predicting vibration of a drilling operation. The vibration information can include axial, lateral or torsional vibration of a drill string.

Abstract: A fitness system for enhancing the effectiveness and efficiency of physical training and/or exercise by a user comprises uses (1) a plurality of sensors that are worn by an exercising user and which generate data concerning monitored body processes pertaining to the exercise's effects on the user's body, (2) a processor operates under software control for processing, storing, and analyzing the data, and sending the processed data to a host device using a wireless communication protocol to communicate desired adjustments to the exercise in real time. The host device can be a smartphone, tablet computer or other web accessible device that can display and communicate bilaterally with the processor.

Abstract: Data collected during reservoir monitoring may include fiber optic measurements utilizing a distributed sensing system. Downhole monitoring with the distributed sensing system may generate large amounts of data. For example, the system may be capable of producing the functional equivalent of tens, hundreds, or even thousands of sensors along a length of a wellbore. Continuous monitoring of various properties, including temperature, pressure, Bragg gradient, acoustic, and strain, may create a large volume of data, possibly spanning into several gigabytes. Embodiments of the present invention provide techniques for analyzing a large volume of measurements taken in a wellbore without compromising on the integrity of data.

Abstract: A blowout rate correction system comprises a sensor and a processor in communication with the sensor. The sensor is to measure sound characteristics associated with an exit point of a borehole. The processor is to determine a blowout rate of hydrocarbons exiting the borehole based on the sound characteristics. In some embodiments, the processor activates a device when the blowout rate exceeds a selected threshold. Additional apparatus, methods, and systems are disclosed.

Abstract: A tool for use in a borehole penetrating a formation method and a method for using the tool is disclosed. The tool includes a gyroscope for obtaining a first measurement of a rotation rate of the apparatus and at least one accelerometer for obtaining a second measurement of the rotation rate of the apparatus. A processor generates an estimate of the rotation rate using at least one of the first measurement of rotation rate and the second measurement of rotation rate. The estimate of the rotation rate is sued to determine a rotational position of a formation parameter measurement obtained during rotation of the apparatus in the borehole.

Abstract: Examples of techniques for monitoring a component used in well operation are disclosed. In one example implementation according to aspects of the present disclosure, a method may include: receiving, by a processing system, sensor data from a sensor, wherein the sensor collects data relating to a component used in the well operation; analyzing, by the processing system, the sensor data to determine whether the component used in the well operation is experiencing an error condition; and alerting, by the processing system, a user of the error condition when it is determined that the component used in the well operation is experiencing an error condition.

Abstract: Method for estimating porosity and water saturation or other geological parameters of a subsurface region when the lithology of the region is unknown, requiring only geophysical data from remote surveys. The geophysical data are inverted (14-18) treating lithology as a third, and discrete, unknown model parameter (12) to be solved for in the inversion. A technique for solving mixed integer non-linear programs may be used. Suitable rock physics relationships (13) are used to relate the desired geological parameters to the geophysical model parameters required for simulating the geophysical data in the inversion process.

Abstract: A method for drilling a well includes prescribing a drill recipe using a drill analysis engine based on a field-specific model. The drill recipe identifies prescribed segments. Each prescribed segment of the prescribed segments includes a start depth. The method further includes initiating drilling of the well based on the drill recipe; detecting a drill event inconsistent with the drill recipe; prescribing an adjusted drill recipe using the drill analysis engine based on the field-specific model in response to the drill event, the adjusted drill recipe including adjusted prescribed segments; and drilling the well based on the adjusted drill recipe.

Abstract: Methods for drilling a wellbore within a subsurface region and drilling assemblies and systems that include and/or utilize the methods are disclosed herein. The methods include receiving a plurality of drilling performance indicator maps, normalizing the plurality of drilling performance indicator maps to generate a plurality of normalized maps, adaptive trending of the plurality of drilling performance indicator maps to generate a plurality of trended maps, summing the plurality of trended maps to generate an objective map, selecting a desired operating regime from the objective map, and adjusting at least one drilling operational parameter of a drilling rig based, at least in part, on the desired operating regime.

Abstract: Systems and methods for controlling a drilling rig. The system includes a first layer including a plurality of subsystem controllers coupled with a plurality of rig subsystems, the plurality of subsystem controllers being configured to control operating parameters of the plurality of rig subsystems. The system also includes a second layer configured to receive information from the first layer based on an operation of the plurality of rig subsystems, and to provide control of the plurality of rig subsystems. The system further includes a third layer configured to execute one or more process applications and to provide a task-based command to the second layer.

Abstract: A system and method for modeling seismic data using time preserving tomography including storing an initial set of parameter values representing an initial seismic data model. The initial seismic model may correspond to at least two or more ray pairs. Each ray pair may have a traveltime. An altered model may be generated by altering two or more parameter values in the initial set of parameter values for each of two or more ray pairs in the initial model. Altering one parameter value without altering the remaining of the two or more parameter values may correspond to a change in the traveltime of each of the ray pairs, while altering the two or more parameter values in combination typically corresponds to no net change in the traveltime of each of the ray pairs.

Abstract: The invention relates to systems, processes and apparatuses for determining a rig-state of a drilling rig during a wellbore drilling operation and detecting and mitigating drilling dysfunctions. These systems, processes and apparatuses provide a computer with a memory and a processor, a plurality of sensors associated with a wellbore drilling operation for acquiring time series data wherein the data are formatted for sample and bandwidth regularization and time-corrected to provide substantially time-synchronized data, a processing graph of data-stream networked mathematical operators that applies continuous analytics to the data at least as rapidly as the data are acquired to determine dynamic conditions of a plurality of rig conditions associated with the wellbore drilling operation and determining a rig-state from the plurality of rig conditions.

Abstract: A method for optimizing drilling includes initializing values of a plurality of drilling operating parameters and drilling response parameters. In a computer, an initial relationship between the plurality of drilling operating parameters and drilling response parameters is determined. A drilling unit to drill a wellbore through subsurface formations. The drilling operating parameters and drilling response parameters are measured during drilling and entered into the computer. A range of values and an optimum value for at least one of the drilling response parameters and at least one of the drilling response parameters is determined in the computer. A display of the at least one of the plurality of drilling operating parameters and the at least one of the drilling response parameters is generated by the computer.

Abstract: A method of drilling a well within a target stratum. The method can include drilling based upon a target window created from previously collected and/or extrapolated data. Data is collected while drilling and the target window can be adjusted “on the fly” as well as updating and correcting previously collected data. The method can be repeated to ensure optimal drilling efficiency and minimal down time while drilling.

Abstract: Proposed is a system and a method for a parametric risk transfer system based on automated location-dependent probabilistic tropical storm risk and storm impact forecast, wherein weather measuring parameters of weather events are measured by means of a plurality of delocalized distributed weather flow stations and transmitted to a central system, and wherein the measured weather measuring parameters at least comprise measuring parameters of wind speed and/or maximum wind speed within a predefined time frame. A spatial high-resolution grid comprising grid cells is generated over a geographical area of interest, and a wind field profile is dynamically generated, wherein by triggering an indexed wind field parameter of the wind field profile exceeding a predefined trigger, an output activation signal is generated based on the wind field parameter and transmitted to an associated activation device, wherein the operation of the activation device is steered by the transmitted output activation signal.

Abstract: An embodiment of a method of performing an energy industry operation includes storing one or more sets of instructions at a storage location accessible by a controller configured to control aspects of an energy industry operation, the one or more sets of instructions retrieved from a library of sets of instructions, each set of instructions prescribing a standard procedure for performing a process forming part of the energy industry operation, the standard procedure based on best operating practices developed from previously performed operations independent of the process to be performed. The method also includes deploying a carrier in a borehole in an earth formation and performing an energy industry operation, monitoring the operation and, in response to detecting a condition associated with the process, automatically retrieving the set of instructions corresponding to the process, and automatically performing the process by the controller according to the retrieved set of instructions.

Abstract: The present disclosure generally relates to synthetic logging for reservoir stimulation. A synthetic logging method for stimulating a reservoir includes: training a machine learning algorithm using historical or exploratory data; and generating a synthetic elastic property log of the reservoir by supplying the trained machine learning algorithm with data acquired from a production wellbore.

Abstract: Various implementations directed to analyzing a reservoir using fluid analysis are provided. In one implementation, a method may include determining mud gas logging (MGL) data based on drilling mud associated with a wellbore traversing a reservoir of interest. The method may also include determining first downhole fluid analysis (DFA) data based on a first reservoir fluid sample obtained at a first measurement station in the wellbore. The method may further include determining predicted DFA data for the wellbore based on the first DFA data. The method may additionally include determining second DFA data based on a second reservoir fluid sample obtained at a second measurement station in the wellbore. The method may further include analyzing the reservoir based on a comparison of the MGL data and a comparison of the second DFA data to the predicted DFA data.

Abstract: A sensor information collecting apparatus includes: a sensor module including a sensor; a sensor amplifier; an acceleration sensor; a control unit; a power supply unit; an illumination unit; an illumination driver; and a battery, which supplies a battery voltage to the acceleration sensor, the control unit, and the power supply unit, wherein, when an acceleration level is equal to or more than a threshold value for data-storing, the control unit activates the sensor amplifier and controls the memory to store the detection data, and wherein, when the acceleration sensor detects an acceleration level which is less than the threshold value for data-storing and is equal to or more than a threshold value for data-transmitting, the control unit outputs an optical communication signal and the illumination driver controls the illumination unit to emit light, on which the optical communication signal is superimposed.

Abstract: A method and apparatus for communicating incremental depth and/or other useful data of a downhole tool. The incremental depth and/or other useful data of the downhole tool being communicated by measuring at least one change in the downhole system, detecting the change downhole, and subsequently determining the incremental depth and/or other useful data of the downhole tool.

Abstract: A technique facilitates diagnosis of a telemetry system, such as a mud pulse telemetry system or an electro-magnetic telemetry system. The technique comprises operating a telemetry system in a wellbore and collecting a variety of data. The data may relate to a rig state, a downhole state, a signal state, a surface state, and/or other suitable types of data. The data is processed to determine whether states of operation indicated by the data match states indicating a problem with operation of the telemetry system. If a problem is detected, appropriate information regarding the problem is transmitted for use in correcting the problem.

Abstract: Respective embodiments disclosed herein include methods and apparatuses (1) for surveying a mine bench or other material body using at least seismic data obtained via geophone and measurement module data synchronized via a wireless link; (2) for generating hyperspectral panoramic imaging data of a blast hole or other borehole; or (3) for allowing a neural network to facilitate a differential blast design that targets a first bench part more weakly than the differential blast design targets a second bench part (along the same mine bench) at least partly based on data indicative of a much higher concentration of a valuable material in the second bench part than in the first.

Abstract: Disclosed are control apparatus and methods for direct control in automated drilling. The control apparatus can include a display, a control unit, and an input device for receiving a plurality of measurements comprising one or more of present depth, present bit position, inclination, azimuth, top drive position, magnetic toolface, gravity toolface, a target control parameter. The control apparatus is configured to generate a drill string position indicator relating to a present depth and a present bit position. The control unit is configured to generate a vertical bar graph inclination indicator and a horizontal bar graph display azimuth indicator. The control unit is configured to generate a top drive position index. The control unit is configured to generate a toolface rosebud and a control parameter display. The control unit is configured to iteratively update the display in substantially real time.

Abstract: A method of optimizing the cross-sectional shape of a logging tool sensor includes the step of, for a given major axis dimension, selecting the minor axis dimension such that for a circular borehole geometry the cross-sectional area of the space between the sensor and a said circular borehole with which the sensor is pressed into contact is minimized. Logging tools optimized according to this technique exhibit beneficial sensor stand-off characteristics.

Abstract: An embodiment of a method of drilling a secondary borehole from a primary borehole includes deploying a drilling assembly at a selected location in the primary borehole in an earth formation, and operating the drilling assembly and a drill bit to form an exit trough in a borehole wall. Operating includes controlling one or more operational parameters including at least a rate of lateral penetration of the drill bit into the formation as a function of time during formation of the exit trough based on at least one of a mathematical model and measurement data collected from one or more sensors, and in response to determining that the exit trough has exited the primary borehole, drilling the secondary borehole away from the primary borehole.

Abstract: Formation properties in a vertical section of a wellbore are determined by considering the vertical section as consisting of one or more segments. Measurements are obtained with a directional resistivity tool at two or more measurement stations within each segment for which the complex 0th harmonic coefficients for the obtained measurements are non-trivially different from one another. For each such segment, the phase shift and attenuation are determined using the complex 0th harmonic coefficients obtained for that segment and an inversion is performed for the formation properties using the determined phase shift and attenuation for that segment. Formation properties for that segment may be output to a display or memory storage device. For certain segments, one or more gain factors may be obtained. The gain factors are used to correct the measured voltages for certain neighboring segments and the corrected voltages inverted to obtain anisotropy and formation structure.

Abstract: Apparatus, computer readable medium, and program code for identifying rock properties in real-time during drilling, are provided. An example of an embodiment of such an apparatus includes a downhole sensor subassembly connected between a drill bit and a drill string, acoustic sensors operably coupled to a downhole processor, a borehole telemetry system, downhole and surface data transmitting interfaces, and a surface computer operably coupled to the downhole data transmitting interface. The downhole processor is adapted to perform operations including receiving raw acoustic sensor data resulting from rotational contact of the drill bit with rock, transforming the raw acoustic sensor data into the frequency domain, filtering the transformed data, and deriving acoustic characteristics from the filtered data. The surface computer is adapted to perform operations including deriving petrophysical properties from the acoustic characteristics directly or by utilizing a petrophysical properties evaluation algorithm.

Abstract: Methods, systems and products for evaluating a downhole component condition for a drilling assembly in a borehole. Methods include estimating a bending moment on the component at a selected depth along the borehole; estimating a number of rotations of the component at the selected depth; and estimating the condition of the component using the estimated bending moment and the estimated number of rotations at the selected depth. Estimated bending moment may be derived from a borehole model using an estimated deviation on a selected length of the borehole about the selected depth. The condition may be accumulated fatigue or estimated remaining useful life. Estimating the condition may include tracking a total estimated number of rotations wherein the component is subjected to bending moment values in a corresponding moment window, which may be greater than a predetermined threshold bending moment. Weight factors may be associated with at least one moment window.

Abstract: Various embodiments include apparatus and methods to operate a measurement process in a borehole that uses a symmetric sensor structure or a sensor structure operable to mimic a symmetric sensor structure to provide structural compensation. Apparatus and methods can include a data processing unit to generate compensated signals based on the measurement signals and to determine formation parameters using the compensated signals. Additional apparatus, systems, and methods are disclosed.

Abstract: A process for reducing wellbore instability includes inputting pre-drilling assessment information into an hydraulics analysis and wellbore stability application, inputting a well plan into the hydraulics and wellbore analysis application, inputting a parameter measured at the wellsite into the hydraulics and wellbore stability analysis application, inputting an observation made at the wellsite into the hydraulics and wellbore stability analysis application, integrating the pre-drilling assessment information, the measured parameter, and the observation into the wellbore strengthening analysis application, and adjusting a drilling fluid parameter in response to the integrated pre-drilling assessment information, the measured parameter, and the observation.

Abstract: Embodiments are generally directed to neural network training for library-based critical dimension metrology. An embodiment of a method includes optimizing a threshold for a principal component analysis of a spectrum data set to provide a principal component value, estimating a training target for one or more neural networks, training the one or more neural networks based both on the training target and on the principal component value provided from optimizing the threshold for the principal component analysis, and providing a spectral library based on the one or more trained neural networks.

Abstract: Methods and systems for monitoring, analyzing, and characterizing well bores and reservoir fluids in a subterranean formation are provided. In particular, methods and systems for determining and using correction coefficients for quantitative analysis of gas samples extracted from fluids at a well site based on Fick's laws of diffusion are provided. In one embodiment, the systems include: a gas trap configured to extract one or more gaseous samples from a fluid at a well site; a gas analyzer configured to receive one or more gaseous samples from the gas extraction system and generate data regarding the amount of one or more gas species in the gaseous sample; and an information handling system communicatively coupled to the gas analyzer that is configured to use data received from the gas analyzer to determine an extraction efficiency coefficient for the gas species.

Abstract: A computer-assisted method for optimizing a drilling tool assembly, the method comprising defining a desired drilling plan; determining current drilling conditions; determining current drilling tool parameters of at least two drilling tool assembly components; analyzing the current drilling conditions and the current drilling tool parameters to define a base drilling condition; comparing the base drilling condition to the desired drilling plan; determining a drilling tool parameter to adjust to achieve the desired drilling plan; and adjusting at least one drilling tool parameter of at least one of the two drilling tool assembly components based on the comparing the base drilling condition to the desired drilling plan.

Abstract: A well drilling method can include detecting a drilling event by comparing a parameter signature generated during drilling to an event signature indicative of the drilling event, and automatically controlling a drilling operation in response to at least a partial match resulting from comparing the parameter signature to the event signature. A well drilling system can include a control system which compares a parameter signature for a drilling operation to an event signature indicative of a drilling event, and a controller which controls the drilling operation automatically in response to the drilling event being indicated by at least a partial match between the parameter signature and the event signature.

Abstract: A method for designing a drilling tool assembly, having a drill bit disposed at one end includes defining initial drilling tool assembly design parameters; calculating a dynamic response of the drilling tool assembly; adjusting a value of a drilling tool assembly design parameter; and repeating the calculating and the adjusting until a drilling tool assembly performance parameter is optimized.