A system and method for measuring flatness and warpage of a surface

Abstract

The present invention describes a novel system (100) and method for measuring the flatness and warpage of a surface (108) of a product. The system (100) comprises a sensing unit (104) with a plurality of sensors (106) mounted onto it, which detect surface undulations through contact and / or non-contact measurement processes. These sensors (106) output a voltage signal proportional to the depth of warpage detected. The voltage signal is then processed in the signal processing module (110) of the display module (102). The display module displays the measured surface readings on a display screen (112) and includes a sensor detection module to detect the type of sensors attached to the sensing unit (104). In an alternate embodiment, a 2D sensor module is provided with a matrix of position sensors built into the sensing unit, allowing for surface contour mapping and 2D undulation measurement along the entire face of the machined part.

Description

[0001] TECHNICAL FIELD

[0002]

[0001] The present invention relates generally to a system adapted to measure and records the flatness of the surface of a product. More specifically, the present invention relates to a system comprising a display module that displays one-dimensional / two dimensional undulations of a product' surface in response to a signal received from the sensing unit attached to it via a connecting means. The present system includes an integrated data logger that enables the recording of said undulations in a storage drive.

[0003] BACKGROUND ART

[0004]

[0002] in present times, measuring tools such as flatness gauges, monochromatic light, optical flats, and the like have been widely used in industry to identify warpage and varying undulations of the surface of any product. Analyzing surface flatness is extremely important for the functional use of many glass products or precision mechanics involved in holding optics and glass components. This involves characterizing the surface flatness for the most diverse areas of use. Potential applications include quality control inspection of warpage and flatness in Ceramic Tiles, Engine Cylinder Head Blocks, Rolling Stock Body Shells and so forth.

[0005]

[0003] In factories, more specifically in tiles or marble industry, undulations on Ceramic Tiles are presently measured in Quality Testing Labs, where multiple tests are performed to determine the quality and strength of tested specimen. This process usually involves a stationary jig where the Tile specimen is placed. One or more depth gauges are affixed on amounting piece and subsequently on the tile surface. As the depth gauge is moved along the surface of the specimen, the deviation of the spring-loaded plunger translates to a positive or a negative undulation with reference to a reference value corresponding to zero undulation. Multiple such readings are obtained from various points along the surface of the tile.

[0006]

[0004] In PCB [printed circuit board] industry, where the plurality of electrical components are mounted the PCB surface, measurement of undulations such as warpage is considered as essential process. Flatness of printed circuit boards is determined by two characteristics of the product; these are known as bow and twist. The bow condition is characterized by a roughly cylindrical or spherical curvature of the board while its four corners are in the same plane. In this industry, Laser based optoelectronic sensors are installed in an elaborate fashion facing the assembly line where-in mass produced PCBs are rolled out. Complex hardware and software work in tandem to detect warpages in the range of microns as the mass-produced PCBs cross the line of sight of these laser beams. This method, though accurate and reliable, is expensive to deploy and maintain. This system of warpage detection is neither portable nor handheld.

[0007]

[0005] Measurement of micro-undulations on the surface of an engine head block or a fuel pump is an integral part of the quality control process in the auto-parts manufacturing industry. This process is carried out by manufacturers of all engines ranging from a small water pump to a giant ship. A straight edge is placed on the top surface of the engine head block. A feeler gauge is then placed under the straight edge. The maximum depth a feeler gauge penetrates under the straight edge corresponds to the maximum warpage measured on the surface of the engine block. This method is time-consuming and susceptible to human errors.

[0008]

[0006] In other application area such as rail car manufacturers use the aforementioned feeler gauge method to determine warpages in the order of millimeters along the surface of a rail car body shell. It typically takes an 8-hour shift to measure and record such warpage readings on the entire outer surface of the car body shell. In all the above use cases, measurements are either made manually or by a sensor-based system. An engineer or a technician then compiles the raw data into a meaningful report for the stakeholders. Further, depending upon the application area, a variety of devices has been employed to measure undulations which further leads to excessive cost. For example, to measure flatness of a cylinder's surface a device with spring type sensor has been used, while measuring warpage of a PCB unit, a different type of sensor like optical sensor has been employed. Using different types of devices for variety of application leads to less efficiency and more financial loss.

[0009]

[0007] In order to overcome the drawbacks that are discussed above, various patent literatures have been introduced in the prior arts. For example, the United States patent US4841767A titled 'Device for measuring flatness defects in a strip' discloses device for measuring flatness defects in a strip, e.g., rolled metal sheets, by the use of sensors. The voltage is measured within an amplitude measuring interval smaller than the voltage variation interval after the pulse, each sensor is associated with a correction transformer capable of delivering on each energizing pulse an adjustable correction voltage algebraically added to the voltage at the terminals of the secondary winding of the sensor and whose value, at the instant of measurement, is determined so as to bring the measured voltage within the measurement interval of the converter.

[0010]

[0008] Another United States patent US6629373B1 discloses a metrological instrument for measuring a characteristic of a surface of a workpiece, the instrument comprising a measurement unit and a user-interface unit separate from the measurement unit. The measurement unit has a sensor which follows a measurement path across a surface and means for deriving a signal indicative of a characteristic of the surface as the sensor follows the surface. The user-interface unit has means for providing a user with an indication of a surface characteristic measured by the sensor. The measurement unit and the user-interface unit have communication means for enabling remote communication of information relating to a measurement between the measurement and user-interface units.

[0011]

[0009] Further a United States patent document US5519944A discloses a device for measuring the straightness of a conductive object includes a plurality of capacitive distance sensors which are aligned along an axis of a ruler to be placed on the object. Circuits are provided for indicating the measurements provided by each sensor. However, none of the aforementioned reference discloses a measurement apparatus that employs the voltage signal corresponding to the warpage detection, in order to determine the flatness of the surface. The references further lack in providing the variety of position sensors depending upon the application of measurement apparatus.

[0012]

[0010] Furthermore, the solutions available in the prior arts are very expensive to deploy, requires complex calibration processes to measure surface undulations, and outputs undesirable results which lacks in accuracy. The products which are available in market are very sensitive to outdoor and dusty environment. Polluted environment like this also affects the accuracy of the system and produces misleading results. Furthermore, conventional devices for measuring surface flatness and warpage are bulky, require more space and ambient light compensation.

[0013] [OH] Therefore, there is a need of a system comprising a measurement apparatus which is handheld or portable and configured to measure the flatness and warpage of a product using variety of sensors. The device is able to be used in a more convenient way and also provides a satisfactory solution to the problems and deficiencies associated with the prior art.

[0014] OBJECTS OF THE INVENTION

[0015]

[0012] Some of the objects of the present invention are listed below:

[0016]

[0013] It is an objective of the present invention to provide a system and method for measuring flatness and warpage of surface;

[0017]

[0014] It is an objective of the present invention to provide a system comprising at least one sensor configured to detect the surface's undulations and outputs a voltage signal that is proportional to the depth of the detected surface;

[0018]

[0015] It is an objective of the present invention to provide a system comprising a display module that displays the surface's flatness and warpage in response to a signal received from at least one sensor provided with the system;

[0019]

[0016] It is another objective of the present invention to provide a system having a signal processing module that processes the voltage signal received from at least one sensor, and further transmits the signal to the display screen;

[0020]

[0017] It is another objective of the present invention to provide a system having a sensor detection module configured to identify or detect the type of at least one sensor coupled to the system, and further signal processing module performs a set of instructions in accordance with detected type of at least one sensor;

[0021]

[0018] It is further objective of the present invention to provide a system, wherein said at least one sensor is detachably attached to said system through a connecting mechanism facilitating the engagement and disengagement of at least one sensor, based on the application requirement;

[0019] It is further objective of the present invention to provide a system that is adapted to employ contact-based sensors such as Spring return Miniature Linear Potentiometers, as well as non-contact sensors such as laser-based sensors;

[0022]

[0020] It is further objective of the present invention to provide a system that detects the one-dimensional / two-dimensional surface undulations with the help of variety of linear position measurement sensors;

[0023]

[0021] It is furthermore objective of the present invention to provide a system and method that enables the measurement of the flatness and warpage of a surface via a contact-based and / or non-contact based measurement process;

[0024]

[0022] It is furthermore objective of the present invention to provide a system which includes an integrated data logger that records the flatness and warpage data in a USB (universal serial bus) drive.

[0025]

[0023] It is furthermore the object of the present invention to provide a system that is lightweight, portable, cost-effective, and easy to use.

[0026]

[0024] Other objects, features, advantages, and goals of the present invention will be better understood from the following detailed description taken in conjunction with the accompanying drawings.

[0027] SUMMARY OF THE PRESENT INVENTION

[0028]

[0025] The present invention discloses a system and method for measuring flatness and warpage of a surface with the help of one or more sensors. More specifically, the present invention discloses a system and method which provides an effective, accurate, less time consuming and reliable approach to measure one-dimensional and two-dimensional surface undulations of a product.

[0029]

[0026] According to an aspect of the present invention, there is provided a system for measuring flatness and warpage of a surface, said system comprises: at least a sensor positioned to measure the flatness and warpage of the surface and outputting at least a voltage, wherein the voltage signal is proportional to the maximum warpage depth detected by said sensor; a signal processing module for processing at least a signal received as at least a voltage from at least the sensor; a display module for displaying the measured flatness and warpage; a power source to supply electric power to said system; a control unit; and a storage module.

[0030]

[0027] In one embodiment of the present invention, the said sensor is selected from a group of linear position measurement sensors.

[0031]

[0028] In one embodiment of the present invention, the sensor comprises Spring return Miniature Linear Potentiometers, Diffuse type Laser Photoelectric Sensors, Time-of-Flight (ToF) sensors, Linear Variable Differential Transformer (LVDTs), Infra-Red Transceivers, Ultrasonic Transducers, LED-Photodiode array.

[0029] In one embodiment of the present invention, wherein said sensor is configured to detect the warpage of any metal and non-metal product up to 20 mm.

[0032]

[0030] In one embodiment of the present invention, wherein said sensor are arranged on a Printed circuit board (PCB) in a linear manner or fashion with a gap of (x mm).

[0033]

[0031] In one embodiment of the present invention, wherein said sensors are installed in a way to form a matrix-type structure.

[0034]

[0032] In one embodiment of the present invention, the system further comprises a sensor detection module configured to detect the type of said sensor based on its measurement range, accuracy, resolution, and other electrical parameters pertinent to its operating range.

[0035]

[0033] In one embodiment of the present invention, the system employs a contact-based process to determine the surface undulations.

[0036]

[0034] In one embodiment of the present invention, wherein said sensor also detects the surface undulations via non-contact measurement process.

[0037]

[0035] In one embodiment of the present invention, wherein said system is handheld or portable.

[0038]

[0036] In one embodiment of the present invention, the system is provided with a robot which scans the surface of a product, in order to identify the flatness and warpage of a surface.

[0039]

[0037] According to an aspect of the present invention, there is provided a method for measuring flatness and warpage of a surface, said method comprising the following steps: placing a measurement apparatus against the surface to determine flatness and warpage; generating at least a signal from at least a sensor, said signal is proportional to the maximum warpage depth detected by said sensor; processing said signal in a signal processing module, the signal is received as a voltage signal from at least the sensor; wherein signal processing module evaluates the data pertaining to the surface warpage in response to the signal received from said sensor; transmitting said processed signal to a display module of the measurement apparatus; displaying the measured flatness and warpage in at least one parameter corresponding to the generated signal, via the display module; and storing the measured flatness and warpage in a storage module.

[0040]

[0038] In one embodiment of the present invention, the method comprising: detecting a type of said sensor via a sensor detection module provided within the measurement apparatus.

[0041]

[0039] In one embodiment of the present invention, wherein the method employs a sensor that is selected from a group of linear position measurement sensors.

[0042]

[0040] In one embodiment of the present invention, wherein the method employs a sensor that comprises Spring return Miniature Linear Potentiometers, Diffuse type Laser Photoelectric Sensors, Time-of-Flight (ToF) sensors, Linear Variable Differential Transformer (LVDTs), Infra-Red Transceivers, Ultrasonic Transducers, LED-Photodiode array.

[0041] In one embodiment of the present invention, wherein said measurement apparatus of the method claim may contact the surface or provided at a distant from the surface, depending on the type of said at least sensor.

[0043]

[0042] In the context of the specification, the term "memory unit" is considered to be inclusive of volatile memory units such as Static Random Access Memory (SRAM) and Dynamic Random Access Memory (DRAM) of types such as Asynchronous DRAM, Synchronous DRAM, Double Data Rate SDRAM, Rambus DRAM, and Cache DRAM, etc.

[0044]

[0043] In the context of the specification, the term "processor" is considered to be inclusive of a general-purpose processor, a Field Programmable Gate Array (FPGA), an ARM-based processor, or an Application Specific Integrated Circuit (ASIC), etc..

[0045]

[0044] The following detailed description is illustrative and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will be apparent by reference to the following detailed description in conjunction with the accompanying drawings.

[0046] BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

[0047]

[0045] The accompanying drawings illustrate the best mode for carrying out the invention as presently contemplated and set forth hereinafter. The present invention may be more clearly understood from a consideration of the following detailed description of the preferred embodiments taken in conjunction with the accompanying drawings wherein like reference letters, and numerals indicate the corresponding parts in various figures in the accompanying drawings, and in which:

[0048]

[0046] Fig. 1 illustrates a perspective view of a system in accordance with an embodiment of the present invention;

[0049]

[0047] Fig. 2 illustrates a side view of the system when applied against a surface, in accordance with an embodiment of the present invention;

[0050]

[0048] Fig. 3 illustrates a side perspective view of the sensing unit disclosing plurality of sensors, in accordance with an embodiment of the present invention;

[0051]

[0049] Fig. 4 illustrates a perspective view of a display module of the system, in accordance with an embodiment of the present invention;

[0052]

[0050] Fig. 5 illustrates a bottom view of the display module having electrical connectors, in accordance with an embodiment of the present invention;

[0053]

[0051] Fig. 6 illustrates a matrix of position sensors of the system, in accordance with one embodiment of the present invention; and

[0054]

[0052] Fig. 7 illustrates a perspective view of a sensing unit for measuring surface flatness, in accordance with alternate embodiment of the present invention.

[0053] Fig. 8 shows a flow chart for the operation of the exemplary system, in accordance with an embodiment of the present invention.

[0055]

[0054] Fig. 9 shows a system with LVDT sensor array, in accordance with an embodiment of the present invention.

[0056]

[0055] Fig. 10 shows a system with infrared sensor module, in accordance with an embodiment of the present invention.

[0057]

[0056] Fig. 11 shows a system with laser sensor module, in accordance with an embodiment of the present invention.

[0058]

[0057] While the present invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that the drawings and detailed description thereto are not intended to limit the invention to the particular form disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present invention as defined by the appended claims and equivalents thereof.

[0059] DETAILED DESCRIPTION

[0060]

[0058] Embodiments of the present invention disclosure will be described more fully hereinafter with reference to the accompanying drawings in which like numerals represent like elements throughout the figures and in which example embodiments are shown.

[0061]

[0059] The detailed description and the accompanying drawings illustrate the specific exemplary embodiments by which the disclosure may be practiced. These embodiments are described in detail to enable those skilled in the art to practice the invention illustrated in the disclosure. It is to be understood that other embodiments may be utilized, and other changes may be made, without departing from the spirit or scope of the present disclosure. The following detailed description is therefore not to be taken in a limiting sense, and the scope of the present invention disclosure is defined by the appended claims. Embodiments of the claims may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

[0062]

[0060] It is envisaged that a system and a method is provided for measuring the flatness and warpage of a product using one or more sensors. The proposed system is configured to measure surface flatness and warpage of metal and non-metal products. In accordance with preferred embodiment, the present system is able to measure flatness of a surface of the product having variety of shapes and sizes. In one embodiment, the present system can measure the flatness of smooth surface, rough surfaces, including flat surfaces as well as contour surfaces. The present system can be used for quality control inspection in variety of industrial application such as PCB industry, automobile industry, steel industry, tiles industry, and the like.

[0061] The system basically includes a sensing unit comprising at least one sensor configured to determine one-dimensional and two-dimensional flatness and warpage of the product's surface. Depending on the application, the system may employ a sensing unit that houses an array of sensors forming a matrix, positioned to measure the flatness and warpage of the surface and outputting at least a voltage, wherein the voltage signal is proportional to the maximum warpage depth detected by said sensors. The sensing unit is coupled to a display module via a connecting mechanism that facilitates detachable connection between them.

[0063]

[0062] The display module comprises a sensor detection module, a signal processing module, a display screen, a storage module, and a power source. The sensor detection module detects the type of sensors provided in the device, and the signal processing module processes the signal in accordance with the detected type of sensors. The display module is configured to represent the surface measurements of the product in one or more parameters corresponding to the signal received from the sensors. The storage module stores the measurement data.

[0064]

[0063] The plurality of sensors can be selected from a group of linear position measurement sensors, including Spring return Miniature Linear Potentiometers, Diffuse type Laser Photoelectric Sensors, Time-of-Flight (ToF) sensors, Linear Variable Differential Transformer (LVDTs), Infra-Red Transceivers, Ultrasonic Transducers, LED-Photodiode array, and the like. The sensors can detect the warpage of any metal and non-metal product up to 20 mm.

[0065]

[0064] The device can employ both contact and non-contact measurement processes, depending on the type of sensors used. It can be handheld or portable and includes an integrated data logger that records the flatness and warpage data in a USB drive. The power source is a rechargeable battery that includes lithium-ion, nickel metal hydride, lead-acid, nickel-cadmium, and rechargeable alkaline batteries. The device includes a charging port for charging the battery and a Liquid crystal display (LCD) for displaying the measurements. 065] Referring now to FIG. 1 of the present invention illustrating a perspective view of a system (100), in accordance with an embodiment of the present invention. There is shown a system (100) comprising a display module (102) that is coupled to a sensing unit (104) of the present invention. The sensing unit (104) includes a plurality of sensors (106) configured to determine the flatness and warpage of any surface of a product. The product can be a metal and / or non-metal product having variety of surfaces such as smooth surface, rough surface, and the like. In one embodiment, the system (100) may include one or more sensors that are able to determine onedimensional and two-dimensional undulations of surfaces having flat and contour shapes. The system (100) mentioned in the present application can be used as quality testing tool in various industries such as PCB industry, automobile industry, steel industry, tiles industry, and the like.

[0066]

[0066] The plurality of sensors (106) provided in the sensing unit (104) are selected from a group of linear position measurement sensors. The linear position measurement sensors are specifically employed for measuring the flatness and warpage of a surface. In preferred embodiment, the plurality of sensors (106) includes but not limited to Spring return Miniature Linear Potentiometers, Diffuse type Laser Photoelectric Sensors, Time-of-Flight (ToF) sensors, Linear Variable Differential Transformer (LVDTs), Infra-Red Transceivers, Ultrasonic Transducers, LED-Photodiode array. In alternate embodiment, the flatness and warpage of a surface can also be detected by a robot. This method of robotic scanning provides more efficient and detailed scanning of the target especially in case of two-dimensional flatness error detection.

[0067]

[0067] As shown in the referred figure, the plurality of sensors (106) is mounted on the bottom surface of the sensing unit (104). The sensing unit (104) is placed in contact with the surface being measured and moved across the surface, allowing the sensors to detect any variations in height or depth. In preferred embodiment, the plurality of sensor (106) is of spring return miniature linear potentiometer type, and is able to detect the warpage depth of the surface up to 20 mm. When the sensing unit (104) pressed against the surface (108) of FIG. 2, the plurality of sensors (106) generates an output voltage signal that is proportional to the warpage depth detected by said sensors.

[0068]

[0068] In alternate embodiment, the present system (100) can detect the flatness and warpage of a surface without contacting the said surface. For this purpose, the present system (100) employs a non-contact approach to determine the ID or 2D undulations of a surface. In this embodiment, the plurality of sensors (106) basically includes a diffuse laser photoelectric sensor array configured to emit radiation on said surface. The said laser photoelectric sensor array is automatically detected by the display module (102). The sensing unit (104) measures undulations on the surface of the specimen in the order of micro-metre (pm).

[0069]

[0069] The operator sets the embodiment at a predetermined distance from the surface of specimen. The laser source provided in the laser sensor array emits radiation on the specimen surface. The radiation is reflected by the surface and is further detected by the sensing module of the system (100). In one embodiment, the laser sensor array of the sensing unit (104) employs principles of triangulation to determine the distance between the sensor and the surface being measured. The sensor is moved over the surface being measured while the laser beam is projected onto the surface. As the distance between the sensor and the surface changes due to surface irregularities, the reflected laser beam also changes position on the sensor. By analyzing the position of the reflected laser beam, the sensor can determine the surface's height and curvature at that point.

[0070]

[0070] The voltage signal generated by the plurality of sensors (106) is further processed in the signal processing module (110) in FIG. 2 of the display module (102). The signal processing module (110) in processes the voltage signals pertinent to the detected surface flatness and warpage. The signal processing module (110) is basically an electronic circuit in the display module (102) which receives the voltage signal from the plurality of sensors (106) and converts it into a form that can be used to calculate the flatness and warpage of the surface being measured.

[0071]

[0071] More particularly, in signal processing module (110) the received voltage signal is then analyzed using algorithms and mathematical models that take into account the characteristics of the plurality of sensors (106) and the surface being measured. These algorithms and models may be pre-programmed into the signal processing module or may be calculated in real-time by a microcontroller or other computing device. The processed signal is then used to generate a visual display or output that provides information on the flatness and warpage of the surface (108) being measured.

[0072]

[0072] The display module (102) further includes a display screen (112) of FIG. 4 that displays the surface undulations of the surface (108) in one or more parameters corresponding to a signal received from the plurality of sensors (106). The display screen (112) typically includes an LCD or other type of screen, which can be either monochrome or color, depending on the specific application. The screen is typically designed to be easy to read and understand, and may include various visual indicators, such as graphs, charts, or numerical readouts, to provide a clear and concise representation of the surface being measured.

[0073]

[0073] The display screen (112) may also include a touch-screen interface or other type of input device, which allows the user to interact with the system and control various functions, such as selecting different measurement modes or adjusting the sensitivity of the sensors. In addition to providing real-time measurements of surface flatness and warpage, the display module (102) may also include a data logging function that records measurements over time. This data can be used for quality control purposes or to identify trends and patterns in the measurements that may be indicative of issues with the surface being analyzed. In preferred embodiment, the display module (102) of the present system (100) further includes an integrated data logger that records the flatness and warpage data in a USB (universal serial bus) flash drive or memory unit or storage module (114) of FIG. 4 for further analysis and report generation.

[0074]

[0074] The display module (102) is a critical component of a system for measuring surface flatness and warpage, as it provides the user with real-time feedback on the quality of the surface being analyzed. By displaying this information in a clear and concise manner, the display module enables the user to make informed decisions about how to improve the surface and ensure that it meets the required specifications and tolerances.

[0075]

[0075] According to one embodiment, the display module (102) also includes a power source (116) configured to supply an electric power to said system (100). The power source (116) is a rechargeable battery which includes but not limited to lithium-ion, nickel metal hydride, lead-acid, nickel-cadmium, and rechargeable alkaline batteries. The specific type of battery used may depend on factors such as the required power output, size, and weight of the present measurement system (100). The said power source (116) in FIG. 2 can be charged and discharged multiple times, allowing the present system (100) to be used repeatedly without the need for replacing disposable batteries.

[0076] The display module (100) further includes a control unit which is configured to control at least one operation of the present system (100). The control unit may include a processor configured to process the one or more computing instructions related to the functioning of system (100). The processor executes the program stored in the memory unit of the display module (102). The processor enables the control unit to control the sensing unit (104), sensor detection module, and display module (102) of the system (100). Depending upon the type of sensors (106) attached to the display module (102), the sensor detection module identifies the characteristics of attached sensor, then processor executes the computing instruction related to said sensor and generates the surface measurement data accordingly.

[0076]

[0077] Referring now to Fig. 2 of the present invention illustrating a side view of the system (100) when applied against a surface (108), in accordance with an embodiment of the present invention. In the referred figure, there is shown a system (100) having a sensing unit (104) comprising a plurality of sensors (106) which contacts the surface (108) of the product. The surface (108) has a concave-shaped structure. More particularly the area around the center of surface includes a warpage varying along the length of said surface (108).

[0077]

[0078] In this embodiment, the plurality of sensors (106) is Spring return Miniature Linear Potentiometers which detects the warpage of the surface (108) and generates a voltage signal corresponding to it. The plurality of sensors (106) consist of a linear resistive element and a wiper that moves along the resistive element and are designed to provide a voltage output that is proportional to the displacement of the wiper. The spring return mechanism ensures that the wiper returns to its original position when the external force is removed.

[0078]

[0079] In preferred embodiment, the plurality of sensors (106) is mounted on the sensing unit (104) which is further connected to the display module (102) via a connecting mechanism. Said connecting mechanism facilitates the engagement and disengagement of the sensing unit (104) with respect to the display module (102), which depends on the requirement of the present system (100). The voltage output from the plurality of sensors (106) can be further used to determine the flatness or warpage of the surface (108), by comparing the voltage values obtained at different points. Spring return miniature linear potentiometers are commonly used in applications where high accuracy and reliability are required, and where space is limited. They are also relatively low- cost and easy to integrate into measurement systems.

[0079]

[0080] Referring now to Fig. 3 of the present invention illustrating a side perspective view of the sensing unit (104) disclosing plurality of sensors (106), in accordance with an embodiment of the present invention. As shown in the referred figure, the plurality of sensors (106) is mounted on the sensing unit (104) in a linear fashion with a gap of (x mm), to detect warpage from different points along a longitudinal direction. The arrangement of sensors (106) in a linear fashion allows for more accurate and precise detection of warpage along the length of the surface (108) being measured.

[0080]

[0081] The plurality of sensors (106) are able to detect warpage along a longitudinal direction by measuring the distance between the surface being measured and the sensor at different points along the sensor's linear array. In preferred embodiment, the plurality of sensor (106) outputs a voltage signal proportional a voltage output that is proportional to the displacement of the wiper, which is processed by the signal processing module (110) to determine the degree of warpage at each point along the sensor's linear array. The linear arrangement also allows for easy identification of the location and magnitude of any surface warpage detected, making it a useful tool for quality control and inspection applications.

[0081]

[0082] In accordance with referred figure, the sensing unit (104) of the system (100) further includes a receptacle (120) that facilitates the engagement and disengagement of the display module (102) with respect to the sensing unit (104). The receptacle (120) is designed to provide a detachable connection between the sensing unit (104) and the display module (102), allowing the system to use different types of sensors and display modules.

[0082]

[0083] The detachable connection provided by the receptacle (120) enables the user to easily swap out sensors or display modules, depending on the specific measurement requirements. For example, if a different type of sensor is needed to measure a particular surface, the user can simply disconnect the sensing unit (104) from the display module (102), and replace it with the required sensor. Similarly, if a different type of display module is needed to display the measurements in a different format, the user can simply disconnect the current display module (102) from the sensing unit (104) and replace it with the required display module.

[0083]

[0084] Furthermore, a corresponding connector (122) is provided on the display module (102), which can be receive in the receptacle (120) of the sensing unit (104) causing the engagement between them. Said connector (122) is illustrated in Fig. 5 of the present invention. Overall, the connector (122) and receptacle (120) provided in the display module (102) and sensing unit (104) respectively, allows for a high degree of flexibility and adaptability in the surface flatness and warpage measurement system (100), making it a versatile and reliable tool for a wide range of measurement applications.

[0084]

[0085] Referring now to Fig. 4 of the present invention illustrating a perspective view of a display module (102) of the system (100). The display module (102) of the measurement apparatus plays an important role in presenting the measurements of surface flatness and warpage to the user. It is designed to display the measurements in a clear and readable form in response to the voltage signal received from the plurality of sensors (106).

[0086] The display module (102) includes a liquid crystal display (LCD) screen (112) which can display the measured flatness and warpage in one or more forms. The forms of display can include numerical values, graphical representations, or a combination of both. The LCD screen (112) ensures that the readings are easily readable, even in low-light conditions. In alternate embodiments, the system (100) may also include other types of display screen such as Light emitting diode (LED), Organic light emitting diode (OLED), E-ink display, and the like.

[0085]

[0087] In addition, the display module (102) also includes a charging port (124) that allows the rechargeable power source (116) provided in the module to be charged. This means that the present system (100) can be used for extended periods without worrying about the battery life. Moreover, the display module (102) includes a power level indicator (126) which indicates the remaining power of the power source (116). This ensures that the user is aware of the battery status at all times and can plan accordingly.

[0086]

[0088] Furthermore, the display module (102) includes a memory unit or storage module (114) which stores the measurement readings. This enables the user to retrieve the previous measurements at a later time, providing a record of the surface flatness and warpage. Additionally, the display module (102) is equipped with a USB drive which facilitates the transfer of the measurement readings to an external communication device. This allows for easy sharing of the readings and enables the user to analyze the measurements in greater detail.

[0087]

[0089] Referring now to Fig. 6 of the present invention illustration a matrix (130) formation of the plurality of sensors (106), in accordance with alternate embodiment of the invention. In this alternate embodiment, the system (100) includes a 2D sensor module. The 2D sensor module is designed to enable the measurement of surface contour mapping and 2D undulation measurement along the entire face of the machined part. This is achieved through the use of a matrix of plurality of sensors (106) that are built into the sensing unit (104).

[0088]

[0090] Unlike the linear position sensors used in the previous embodiment, the 2D sensor module uses an array of plurality of sensors (106) arranged in a matrix format to increase the accuracy of the present system. This allows for the detection of surface flatness and warpage at multiple points simultaneously, resulting in a more detailed and accurate measurement of the surface contour. This arrangement of sensors enables the measurement of surface contour mapping and 2D undulation measurement in real-time. The plurality of sensors (106) is designed to detect any changes in surface flatness and warpage along the entire face of the machined part, providing a comprehensive understanding of the surface topography.

[0089]

[0091] This arrangement of sensors is particularly useful for applications where a high level of precision is required, such as in the automotive and aerospace industries. It can also be used in other industries where accurate measurement of surface topography is necessary for ensuring product quality and consistency.

[0092] Referring now to Fig. 7 of the present invention illustrating a perspective view of a sensing unit (200), in accordance with alternate embodiment of the invention. In this alternative configuration, the sensing unit (200) adopts a square structure. On a specific surface of the sensing unit (200), a collection of sensors (202) is incorporated to measure the surface flatness. These sensors are arranged in a matrix pattern on the designated surface of the sensing unit (200).

[0090]

[0093] This unique square-shaped sensing unit offers several advantages. Firstly, the square structure provides a larger surface area for accommodating a greater number of sensors compared to linear or rectangular configurations. This allows for increased sensor density and more comprehensive coverage of the surface being measured. Additionally, the matrix arrangement of sensors enables simultaneous measurement of multiple points on the surface, facilitating faster and more efficient data collection. The matrix design also allows for the detection of surface irregularities and undulations in various directions, providing a more comprehensive analysis of the surface flatness.

[0091]

[0094] Fig. 8 shows a flow chart for the operation of the exemplary system, in accordance with an embodiment of the present invention.

[0092]

[0095] The operation 800 commences at step 802 with the initial step 804 may be placing a measurement system (100) against the surface (108) to determine flatness and warpage.

[0093]

[0096] In an alternate embodiment, surface flatness and warpage are critical parameters that need to be measured accurately in various industries, including manufacturing, aerospace, automotive, and electronics. The assessment of flatness and warpage helps ensure the quality and functionality of components and products. Several measurement systems are currently employed to measure these surface characteristics. Below mentioned are these measurement systems in detail.

[0094]

[0097] Contact Profilometers are widely used instruments that employ a mechanical stylus or probe to measure the profile of a surface. As the stylus scans the surface, it detects height variations and provides data that can be used to evaluate flatness and warpage. By comparing the measured profile to a reference plane, contact profilometers provide valuable insights into the surface irregularities.

[0095]

[0098] Coordinate Measuring Machines (CMM) are versatile measurement systems that utilize a probe to measure surface points in three-dimensional space. Equipped with touch probes or optical probes, CMMs can accurately measure surface profiles and perform 3D scans. By collecting a series of points, CMMs enable the assessment of flatness and warpage with high precision.

[0096]

[0099] Laser Scanning Systems employ laser technology to measure surface topography. These systems project a laser beam onto the surface and capture the reflected light, creating a detailed three-dimensional point cloud of the surface. Through advanced algorithms, laser scanning systems analyze the point cloud data to determine flatness and warpage accurately. These systems are especially effective in capturing complex surface geometries.

[0097]

[0100] Optical Interferometry is a technique that utilizes the interference of light waves to measure surface variations. Optical interferometers project a beam of light onto the surface and compare the phase difference between the reference beam and the beam reflected from the surface. This technique offers exceptional accuracy and is well-suited for precision measurements of flatness and warpage.

[0098]

[0101] Digital Holography combines digital imaging and interferometry principles to measure surface shape and deformation. Digital holography captures interference patterns created by the interaction of a reference beam and a beam reflected from the surface. By analyzingthese patterns, it can determine flatness and warpage with high accuracy. This non-contact method is particularly useful for measuring dynamic surfaces or delicate components.

[0099]

[0102] Vision-based Systems employ cameras and advanced image processing techniques to measure surface topography. These systems capture images of the surface from various angles and analyze the collected images to determine flatness and warpage. Vision-based systems offer advantages such as faster measurements and non-contact operation, making them suitable for high-speed production environments.

[0100]

[0103] Each measurement system has its advantages and limitations, and the choice depends on specific requirements. Factors such as required accuracy, surface type, measurement speed, and application play crucial roles in selecting the appropriate system. It is essential to consider the specific industry standards and tolerances to ensure that the chosen measurement system aligns with the desired level of accuracy and precision.

[0101]

[0104] In conclusion, the measurement of surface flatness and warpage is essential for ensuring product quality and functionality in numerous industries. Various measurement systems, including contact profilometers, CMMs, laser scanning systems, optical interferometry, digital holography, and vision-based systems, are available to assess these surface characteristics. The selection of the appropriate measurement system depends on factors such as accuracy requirements, surface type, measurement speed, and specific application needs. By utilizing these advanced measurement systems, industries can achieve higher levels of quality control and precision in their manufacturing processes.

[0102]

[0105] In an embodiment, the subsequent step 806 the system detects the type of sensor attached. In an embodiment the detection may be carried out by the CPU of the system.

[0103]

[0106] In an embodiment, the next step 808 may be generating a signal from a sensor (106), wherein the signal is proportional to the warpage depth detected by the sensor (106).

[0104]

[0107] In an alternate embodiment, the measurement of surface flatness and warpage requires the use of various types of sensors. These sensors play a crucial role in capturing the necessary data and providing accurate measurements for assessing surface characteristics. Below mentioned are the different types of sensors commonly used for measuring flatness and warpage in detail.

[0105]

[0108] Contact Probes are a commonly used type of sensor for surface measurement. These probes consist of a stylus that physically makes contact with the surface being measured. As the stylus moves along the surface, it detects height variations, which can be used to determine flatness and warpage. Contact probes offer high resolution and can provide precise measurements, particularly for surfaces with relatively small features or tight tolerances.

[0106]

[0109] Optical Sensors utilize optical principles to measure surface topography. One type of optical sensor is the confocal sensor, which uses a confocal microscope to capture high-resolution images of the surface. By analyzing the reflected light, confocal sensors can determine surface height variations and evaluate flatness and warpage. Another type is the laser displacement sensor, which measures the distance to the surface based on the reflected laser beam. These sensors offer non-contact measurement capabilities and are suitable for delicate or sensitive surfaces.

[0107] [HO] Interferometric Sensors are based on the principles of interference of light waves. They utilize the interference patterns created by the interaction of light beams to measure surface variations. One example is the white light interferometer, which uses a broadband light source and a spectrometer to analyze the interference pattern and determine surface height variations. Interferometric sensors provide high precision and are capable of measuring both flatness and warpage with exceptional accuracy.

[0108] [Hl] Structured Light Sensors project a pattern of light onto the surface being measured and capture the deformation of the pattern. By analyzing the deformation, these sensors can determine surface variations and evaluate flatness and warpage. One common type of structured light sensor is the fringe projection system, which projects a series of fringe patterns onto the surface and captures the reflected patterns using cameras. These sensors offer fast measurement capabilities and are suitable for large areas or dynamic surfaces.

[0109]

[0112] Ultrasonic Sensors utilize sound waves to measure surface topography. They emit ultrasonic pulses that bounce off the surface and are detected by receivers. By analyzing the time it takes for the sound waves to return, ultrasonic sensors can determine surface height variations and assess flatness and warpage. These sensors are particularly useful for measuring surfaces with rough textures or in environments with high levels of noise or vibration.

[0110]

[0113] In conclusion, the measurement of surface flatness and warpage relies on a variety of sensors that employ different principles to capture surface topography. Contact probes, optical sensors, interferometric sensors, structured light sensors, and ultrasonic sensors are among the commonly used types. By selecting the appropriate sensor based on the specific requirements of the measurement task, industries can achieve accurate and precise assessments of surface characteristics. These sensors contribute to improved quality control, increased productivity, and enhanced product performance across various industries.

[0111]

[0114] In an embodiment, further at step 810 may be processing the signal in a signal processing module (110), which evaluates the data pertaining to the surface warpage.

[0112]

[0115] In an alternate example embodiment, Signal processing methods play a crucial role in handling and analyzing the signals acquired from sensors used to measure surface flatness and warpage. These methods are employed to extract meaningful information, enhance signal quality, and enable accurate measurements. Below mentioned are some of the different types of signal processing methods commonly utilized in this context.

[0113]

[0116] Filtering is a fundamental signal processing technique that removes noise and unwanted components from the acquired signals. Sensors used for surface measurement may capture various types of noise, such as electrical noise or environmental interference. Filtering methods, such as low-pass filters, high-pass filters, or adaptive filters, can be applied to remove noise and improve the signal quality, ensuring more accurate measurements.

[0114]

[0117] Smoothing is a technique used to reduce noise and irregularities in signals while preserving essential features. Smoothing methods, such as moving average or Savitzky-Golay filtering, help eliminate high-frequency noise and fluctuations, making the signal appear more regular and easier to analyze. Smoothing techniques are particularly useful for enhancing the quality of measured surface profiles and reducing measurement errors caused by noise.

[0115]

[0118] Signal Calibration is an important process that involves correcting the acquired signals to account for system-specific biases or nonlinearities. Calibration methods aim to establish a known relationship between the measured signal and the true physical quantity. By calibrating the sensor output, signal accuracy can be significantly improved, leading to more reliable measurements of surface flatness and warpage.

[0116]

[0119] Feature Extraction is the process of identifying and extracting relevant information or characteristics from the acquired signals. In the context of surface measurement, feature extraction methods analyze the signal to identify specific patterns or attributes related to flatness and warpage. These methods can include peak detection algorithms, Fourier analysis, or wavelet transforms, which allow the identification of significant features in the signal domain.

[0117]

[0120] Signal Segmentation is a technique used to divide the acquired signals into distinct sections or segments for further analysis. Segmentation methods aim to identify relevant regions of interest within the signal that correspond to specific surface features or variations. By segmenting the signal, it becomes possible to focus on specific areas of interest, such as localized warpage or deviations from flatness, facilitating more detailed analysis and measurement.

[0118]

[0121] Statistical Analysis methods are utilized to analyze the statistical properties of the acquired signals. These methods provide valuable insights into the distribution, variability, and trends within the signal data. Statistical techniques, including mean calculation, standard deviation, or correlation analysis, can be employed to characterize the surface flatness and warpage, identify outliers or anomalies, and quantify the level of variation present in the measured signals.

[0119]

[0122] Pattern Recognition and Machine Learning methods can be employed to recognize complex patterns or classify different surface conditions based on the acquired signals. These techniques utilize algorithms and models to train the system to recognize specific features associated with flatness or warpage. By training the system on a set of labeled data, it can learn to accurately classify new signals and provide automated assessment of surface characteristics.

[0120]

[0123] In conclusion, signal processing methods are essential for handling signals acquired from sensors used to measure surface flatness and warpage. Filtering, smoothing, calibration, feature extraction, signal segmentation, statistical analysis, pattern recognition, and machine learning techniques are employed to enhance signal quality, extract relevant information, and enable accurate measurements. By applying these signal processing methods, industries can obtain reliable and meaningful data, leading to improved quality control, process optimization, and enhanced product performance in various applications.

[0121]

[0124] In an embodiment, step 812 may be transmitting the processed signal to a display module (102).

[0122]

[0125] In an alternate example embodiment, signal transmission methods play a crucial role in handling signals from sensors used to measure surface flatness and warpage. These methods ensure the efficient and reliable transfer of sensor data to the display unit for further analysis and visualization. Below mentioned are some of the different types of signal transmission methods commonly employed in this context.

[0123]

[0126] Analog Transmission is a traditional method where the sensor signals are transmitted in their original analog form. This method involves directly transferring the continuous analog signals from the sensors to the display unit through physical connections, such as wires or cables. Analog transmission is simple and cost-effective but may suffer from signal degradation and interference over long distances.

[0124]

[0127] Digital Transmission is a widely used method that converts the analog sensor signals into digital data for transmission. Analog-to-digital converters (ADCs) are utilized to sample and quantize the analog signals into discrete digital values. These digital values are then transmitted to the display unit using various digital communication protocols, such as Universal Serial Bus (USB), Ethernet, or Wi-Fi. Digital transmission offers higher immunity to noise and allows for more reliable and accurate signal reproduction.

[0125]

[0128] Wireless Transmission utilizes wireless communication technologies to transmit sensor data without the need for physical connections. Wireless sensors can directly transmit the measured signals to a receiver or base station, which then relays the data to the display unit wirelessly. Wireless transmission methods, such as Bluetooth, Zigbee, or Wi-Fi, provide flexibility and convenience in terms of sensor placement and system setup, especially in situations where wired connections are impractical or infeasible.

[0126]

[0129] Fiber Optic Transmission involves the use of optical fibers to transmit sensor signals as light pulses. The sensor signals are converted into optical signals using optoelectronic devices and then transmitted through the optical fibers to the display unit. Fiber optic transmission offers several advantages, including high bandwidth, long-distance capabilities, and immunity to electromagnetic interference. It is particularly suitable for applications that require reliable and high-speed signal transmission.

[0127]

[0130] Real-time Transmission is a method that focuses on transmitting sensor signals to the display unit in real-time or with minimal latency. This is crucial for applications where immediate feedback and continuous monitoring of surface flatness and warpage are required. Real-time transmission methods often involve high-speed data acquisition and transmission techniques, such as high-speed digital interfaces or dedicated field bus systems.

[0128]

[0131] Data Logging and Storage is another aspect of signal transmission that involves capturing and storing the sensor data for later analysis and visualization. Data loggers or data acquisition systems are used to record the sensor signals over a period of time. The recorded data can be transferred to the display unit through various methods, such as physical media (e.g., USB drives) or network-based file transfer protocols. Data logging enables offline analysis, historical comparisons, and long-term data storage for further investigations or quality control purposes.

[0129]

[0132] In conclusion, signal transmission methods are essential for handling sensor signals used to measure surface flatness and warpage and transmitting the processed data to a display unit. Analog transmission, digital transmission, wireless transmission, fiber optic transmission, realtime transmission, and data logging / storage are some of the commonly employed methods. The choice of the transmission method depends on factors such as signal quality requirements, distance, convenience, system complexity, and real-time monitoring needs. By utilizing appropriate signal transmission methods, industries can ensure reliable and efficient transfer of sensor data for analysis, visualization, and decision-making processes.

[0130]

[0133] In an embodiment, furthermore at step 814 may be displaying the measured flatness and warpage in the display module (102).

[0131]

[0134] In an alternate example embodiment, display systems play a critical role in visualizing and presenting the measured flatness and warpage of a surface. These systems provide a means for users to interpret and analyze the data, enabling informed decision-making and quality control. Below mentioned are some of the different types of display systems commonly used in this context.

[0132]

[0135] Computer Monitors are widely employed as display systems for surface measurement data. They offer high-resolution screens capable of rendering detailed visualizations of the surface profile, flatness, and warpage. Computer monitors are typically connected to a computer or data processing unit, which processes the acquired data and generates graphical representations or numerical displays. These systems provide a flexible and versatile platform for analyzing and interpreting surface measurement results.

[0133]

[0136] Projectors are used to display surface measurement data on larger screens or surfaces, such as walls or projection screens. They project the visual representations of the measured flatness and warpage onto a larger area, allowing multiple viewers to observe the data simultaneously. Projectors are often employed in collaborative environments or during presentations where a more extensive display area is desired for enhanced visibility.

[0134]

[0137] Head-Mounted Displays (HMDs) provide an immersive visual experience by presenting the measurement data directly to the user's eyes. These displays are worn on the head, resembling goggles or helmets, and feature small screens positioned close to the user's eyes. HMDs are commonly used in virtual reality (VR) or augmented reality (AR) applications, allowing users to visualize and interact with the surface measurement data in a highly immersive and interactive manner.

[0135]

[0138] Touchscreen Displays combine the visual output with touch-sensitive capabilities, enabling users to interact directly with the displayed data. These displays offer intuitive interfaces where users can manipulate and explore the surface measurement data using touch gestures, such as zooming, panning, or rotating. Touchscreen displays are commonly utilized in applications where user interaction and exploration of the data are crucial, providing a hands-on experience.

[0136]

[0139] Data Visualization Software platforms are used to process, analyze, and present the surface measurement data in a visual format. These software applications provide a range of visualization tools, such as 2D and 3D plots, contour maps, color maps, or animations. They allow users to customize the visual representation of the data, apply filters or enhancements, and perform in-depth analysis. Data visualization software platforms offer flexibility and advanced features for exploring and interpreting surface measurement results.

[0137]

[0140] Embedded Displays are integrated into specialized measurement devices or instruments used for surface flatness and warpage assessment. These displays are designed specifically for the device and often offer dedicated features and functionalities tailored to the measurement task. Embedded displays provide real-time visualization of the measured data directly on the instrument, facilitating immediate feedback and on-site analysis.

[0138]

[0141] In conclusion, a variety of display systems are utilized to present the measured flatness and warpage of a surface. Computer monitors, projectors, head-mounted displays, touchscreen displays, data visualization software platforms, and embedded displays are among the commonly employed types. The choice of the display system depends on factors such as the desired visual experience, interaction requirements, collaborative needs, data complexity, and application context. By utilizing appropriate display systems, industries can effectively visualize and interpret surface measurement data, enabling informed decision-making, quality control, and process optimization.

[0139]

[0142] In an embodiment, at final step 816 may be storing the measured flatness and warpage in a storage module (114) and the operation terminates at step 818.

[0140]

[0143] In an alternate example embodiment, storing the measured flatness and warpage data of a surface is essential for future reference, analysis, and quality control purposes. Different types of storage systems are used to securely store and manage this data. Below mentioned are some of the commonly used storage systems in this context.

[0141]

[0144] Local Hard Drives or Solid-State Drives (SSDs) are frequently employed as primary storage systems for surface measurement data. These internal storage devices are directly connected to the measurement equipment, or the computer system used for data acquisition and processing. They provide fast access times, large storage capacities, and reliable data retention. Local hard drives or SSDs are suitable for storing and managing measurement data within the same physical location or for temporary storage before transferring the data to other long-term storage systems.

[0142]

[0145] Network-Attached Storage (NAS) systems offer a centralized storage solution that can be accessed by multiple devices over a network. NAS devices are dedicated servers connected to a local area network (LAN) or a wide area network (WAN). They provide high storage capacity, data redundancy, and convenient access to the stored data from various devices. NAS systems are commonly used in collaborative environments or in situations where multiple users need to access and share the surface measurement data.

[0143]

[0146] Cloud Storage solutions have gained significant popularity in recent years due to their scalability, flexibility, and remote accessibility. Cloud storage providers offer online storage services where surface measurement data can be securely uploaded and stored on remote servers. Cloud storage provides advantages such as automatic backups, data synchronization across multiple devices, and the ability to access the data from anywhere with an internet connection. It also offers scalable storage options, allowing organizations to expand their storage capacity as needed.

[0144]

[0147] Databases are utilized to organize, manage, and store surface measurement data in a structured manner. Relational databases, such as MySQL or PostgreSQL, or NoSQL databases like MongoDB, are commonly employed for this purpose. Databases provide efficient data indexing, retrieval, and querying capabilities, enabling easy access and retrieval of specific measurement data. They also support data integrity and security features, ensuring the reliability and protection of the stored surface measurement data.

[0145]

[0148] Data Archiving systems are used for long-term storage and preservation of surface measurement data. Archiving involves transferring the data from the primary storage systems to secondary storage media, such as tape drives or optical discs. These media offer high storage capacity, long-term data retention, and data integrity. Archiving systems are particularly suitable for storing historical surface measurement data that may need to be retained for regulatory compliance, reference, or future analysis purposes.

[0146]

[0149] Enterprise Content Management (ECM) systems provide comprehensive solutions for managing and storing various types of content, including surface measurement data. ECM systems offer document management capabilities, version control, metadata management, and workflow automation. These systems allow organizations to organize, search, and retrieve the surface measurement data efficiently while maintaining data security and compliance with industry standards.

[0147]

[0150] In conclusion, different types of storage systems are used to store the measured flatness and warpage data of a surface. Local hard drives, solid-state drives, network-attached storage, cloud storage, databases, data archiving systems, and enterprise content management systems are among the commonly employed solutions. The choice of storage system depends on factors such as storage capacity requirements, data accessibility, collaboration needs, data security, and long-term preservation considerations. By utilizing appropriate storage systems, industries can ensure the safe and efficient management of surface measurement data, enabling future analysis, quality control, and decision-making processes.

[0148]

[0151] Fig. 9 shows a system with LVDT sensor array, in accordance with an embodiment of the present invention. A system (900) of FIG. 9 comprising a display module (102) that is coupled to a LVDT sensing unit (904) of the present invention. The sensing unit (904) includes a plurality of sensors configured to determine the flatness and warpage of any surface of a product. Further, the system includes a signal processing module (906) which performs operations on the signals from the sensing unit (904). In some embodiments, the product may be a concrete surface ( 902).

[0149]

[0152] An LVDT (Linear Variable Differential Transformer) sensor is a type of electromechanical transducer used to measure displacement or linear position. It converts mechanical motion or displacement into an electrical signal that can be easily measured and analyzed. LVDT sensors are widely used in various industrial, automotive, and scientific applications where accurate and reliable measurement of linear displacement is required.

[0150]

[0153] The basic structure of an LVDT consists of a primary coil (also known as the primary winding) and two secondary coils wound on a common cylindrical core. The primary coil is excited with an alternating current (AC) signal, typically at a high frequency. When the core, which is typically connected to the object being measured, moves linearly within the coil assembly, it induces varying voltages in the two secondary coils. The differential voltage between the secondary coils is proportional to the displacement of the core within the coil assembly. This differential voltage can be amplified and processed to determine the linear position of the core and, consequently, the object being measured.

[0151]

[0154] LVDT sensors offer several advantages, including high accuracy, good linearity, and a wide measurement range. They are also known for their reliability and durability in harsh environments due to their simple and robust design.

[0152]

[0155] Fig. 10 shows a system with infrared sensor module, in accordance with an embodiment of the present invention. A system (1000) of FIG. 10 comprising a display module (102) that is coupled to an infrared sensor module sensing unit (1004) of the present invention. The sensing unit (1004) includes a plurality of sensors configured to determine the flatness and warpage of any surface of a product. Further, the system includes a signal processing module (1006) which performs operations on the signals from the sensing unit (1004). In some embodiments, the product may be a sheet metal surface ( 1002).

[0153]

[0156] Infrared sensors have emerged as invaluable tools in modern engineering and industrial applications, offering the capability to detect and analyze surface undulations with remarkable precision. This advanced technology, often referred to as infrared profilometry or laser profilometry, leverages the principles of light reflection and time-of-flight measurement to create detailed 3D representations of surfaces. By employing infrared sensors to detect surface undulations, industries have unlocked a wide array of possibilities in quality control, manufacturing, aerospace, and beyond.

[0154]

[0157] At the heart of this technology lies the interaction between an emitter, typically a laser or an infrared light source, and a receiver, usually a photodetector. The sensor initiates the process by emitting a beam of light that is directed towards the target surface. As the light encounters the surface, it reflects back towards the sensor, and the receiver captures the returning light. By analyzing the time it takes for the light to travel to the surface and return, the sensor can calculate the distance between itself and the surface at that specific point. By repeating this process across multiple points on the surface, the sensor generates a dataset of distance measurements.

[0155]

[0158] This dataset, commonly referred to as a point cloud, consists of three-dimensional coordinates that collectively define the surface's shape. Software algorithms are then employed to reconstruct a continuous 3D representation of the object's surface using these data points. The result is an accurate and detailed model that reflects the true geometry of the object, capturing even the slightest undulations or irregularities.

[0156]

[0159] The applications of this technology span a broad spectrum of industries. In manufacturing and quality control, infrared sensors offer a non-destructive means of inspecting machined parts for defects, ensuring that products meet stringent quality standards. Aerospace industries utilize these sensors to monitor the structural integrity of aircraft components, identifying potential issues before they escalate into safety concerns. The automotive sector benefits from the technology as well, using it to reverse engineer components and surfaces, facilitating efficient design processes.

[0157]

[0160] One of the key advantages of using infrared sensors for detecting surface undulations is their exceptional accuracy and resolution. Laser-based sensors, in particular, provide the highest precision, enabling detection of minute irregularities that could otherwise go unnoticed. Furthermore, the speed and efficiency of these sensors make them suitable for real-time applications, enhancing their utility in various industries.

[0158]

[0161] However, it's important to consider certain factors when employing infrared sensors for surface undulation detection. Factors such as ambient lighting conditions and surface reflectivity can influence the accuracy of measurements. Calibration and sensor alignment are critical to ensure reliable results. Additionally, the choice between different types of sensors, such as laser-based or simpler infrared distance sensors, should be based on the specific needs of the application, including the required measurement range and precision.

[0159]

[0162] In conclusion, the utilization of infrared sensors for detecting surface undulations has revolutionized industries that rely on accurate surface analysis. By harnessing the principles of light reflection and time-of-flight measurement, these sensors provide a means to create precise 3D representations of surfaces, enabling the identification of even the slightest irregularities. From manufacturing to aerospace, this technology has proven invaluable in ensuring quality, safety, and efficiency.

[0160]

[0163] Fig. 11 shows a system with laser sensor module, in accordance with an embodiment of the present invention. A system (1100) of FIG. 11 comprising a display module (102) that is coupled to a laser sensor module sensing unit (1104) of the present invention. The sensing unit (1104) includes a plurality of sensors configured to determine the flatness and warpage of any surface of a product. Further, the system includes a signal processing module (1106) which performs operations on the signals from the sensing unit (1104). In some embodiments, the product may be a PCB surface ( 1102).

[0161]

[0164] In the realm of modern engineering and industrial applications, laser sensors have emerged as powerful tools for detecting and characterizing surface undulations with exceptional precision. Leveraging the principles of light amplification by stimulated emission of radiation (laser) and advanced measurement techniques, these sensors have revolutionized the way industries approach quality control, manufacturing, and various scientific investigations. This essay delves into the intricate workings of laser sensors used for detecting surface undulations, highlighting their mechanisms, applications, benefits, and challenges.

[0162]

[0165] At the core of laser sensors for surface undulation detection is the principle of interferometry. Interferometry involves the superimposition of two or more light waves to generate a resultant wave pattern that provides insights into the phase and amplitude differences between the waves. This technique is harnessed to achieve exceptional accuracy in distance measurement. Laser sensors utilize this principle by emitting a laser beam towards the target surface and analyzing the reflected light to infer distance variations.

[0163]

[0166] The process begins with the emission of a coherent laser beam towards the surface of interest. The laser light interacts with the surface, and its reflection is captured by a detector. The reflected light waves interfere with the incident laser beam, resulting in a complex interference pattern. This pattern contains information about the phase shift caused by the change in distance between the sensor and the surface. By analyzing this pattern, the sensor can precisely determine the distance between itself and the surface point, often on the scale of micrometers.

[0164]

[0167] One of the key advantages of laser sensors is their capability to generate highly detailed and accurate 3D representations of surfaces. The sensor scans the surface point by point, collecting distance measurements that collectively form a point cloud dataset. This dataset is then processed using advanced algorithms to reconstruct a continuous and accurate 3D model of the surface. This model not only captures macroscopic undulations but also reveals microscopic details that might be crucial in various applications.

[0165]

[0168] The applications of laser sensors for detecting surface undulations are diverse and encompass a wide array of industries. In manufacturing, these sensors play a vital role in quality control, enabling the detection of defects or deviations in machined parts with unparalleled precision. In aerospace and automotive industries, laser sensors are employed to monitor the structural integrity of critical components, ensuring that any surface irregularities are identified before they compromise safety or performance.

[0166]

[0169] However, employing laser sensors for surface undulation detection comes with certain challenges. The accuracy of the measurements can be affected by factors such as the wavelength of the laser used, environmental conditions, and the reflectivity of the surface. Calibration and alignment are essential to maintain measurement accuracy. Additionally, the complexity of laser interferometry techniques demands specialized knowledge and equipment, potentially limiting their widespread adoption.

[0167]

[0170] In conclusion, laser sensors have redefined the landscape of surface undulation detection in engineering and industry. By harnessing the principles of interferometry and laser technology, these sensors offer unprecedented accuracy and precision in capturing surface topography. Their applications span from quality control to aerospace, contributing to improved safety, performance, and efficiency.

[0168]

[0171] Many modifications and other embodiments of the inventions set forth herein will come to mind to one skilled in the art to which these inventions pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the inventions are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Moreover, although the foregoing descriptions and the associated drawings describe example embodiments in the context of certain example combinations of elements and / or functions, it should be appreciated that different combinations of elements and / or functions may be provided by alternative embodiments without departing from the scope of the appended claims. In this regard, for example, different combinations of elements and / or functions than those explicitly described above are also contemplated as may be set forth in some of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

[0169]

[0172] It is to be understood that the above description is intended to be illustrative, and not restrictive. For example, the above-discussed embodiments may be used in combination with each other. Many other embodiments will be apparent to those of skill in the art upon reviewing the above description.

[0170]

[0173] With respect to the use of substantially any plural and / or singular terms herein, those having skill in the art can translate from the plural to the singular and / or from the singular to the plural as is appropriate to the context and / or application. The various singular / plural permutations may be expressly set forth herein for sake of clarity.

[0171]

[0174] The benefits and advantages which may be provided by the present invention have been described above with regard to specific embodiments. These benefits and advantages, and any elements or limitations that may cause them to occur or to become more pronounced are not to be construed as critical, required, or essential features of any or all of the embodiments.

[0172]

[0175] While the present invention has been described with reference to particular embodiments, it should be understood that the embodiments are illustrative and that the scope of the invention is not limited to these embodiments. Many variations, modifications, additions, and improvements to the embodiments described above are possible. It is contemplated that these variations, modifications, additions, and improvements fall within the scope of the invention.

[0173]

[0176] The present invention has been described with reference to exemplary embodiments. However, it will be readily apparent to those skilled in the art that it is possible to embody the invention in specific forms other than those of the exemplary embodiments described above. This may be done without departing from the spirit of the invention. The described embodiments are merely illustrative and should not be considered restrictive in any way. The scope of the invention is given by the appended claims and their equivalents, rather than the preceding description, and all variations and equivalents which fall within the range of the claims are intended to be embraced therein. Although the invention has been shown and described with respect to certain embodiments, it is obvious that equivalent alterations and modifications will occur to others skilled in the art upon the reading and understanding of the specification. In particular, with regard to the various functions performed by the above-described components, the terms (including any reference to a "means") used to describe such components are intended to correspond, unless otherwise indicated, to any component which performs the specified function of the described component (e.g., that is functionally equivalent) even though not structurally equivalent to the disclosed component which performs the functions in the herein exemplary embodiments of the invention. In addition, while a particular feature of the invention may have been disclosed with respect to only one embodiment, such feature may be combined with one or more other features of other embodiments as may be desired or advantageous for any given or particular application.

Claims

We claim:

1. A system (100) for measuring flatness and warpage of a surface (108), said system (100) comprises: at least a sensor (106) positioned to measure the flatness and warpage of the surface (108) and outputting at least a voltage, wherein the voltage signal is proportional to the warpage depth detected by said sensor (106); a signal processing module (110) for processing at least a signal received as at least a voltage from at least the sensor (106); a display module (102) for displaying the measured flatness and warpage; a power source (116) to supply electric power to said system (100); a control unit; and a storage module (114).

2. The system (100) as claimed in claim 1, wherein said sensor (106) is selected from a group of linear position measurement sensors.

3. The system (100) as claimed in claim 1, wherein said sensor (106) comprises Spring return Miniature Linear Potentiometers, Diffuse type Laser Photoelectric Sensors, Time-of- Flight (ToF) sensors, Linear Variable Differential Transformer (LVDTs), Infra-Red Transceivers, Ultrasonic Transducers, LED-Photodiode array.

4. The system (100) as claimed in claim 1, wherein said sensor (106) is configured to detect the warpage of any metal and non-metal product upto 20 mm.

5. The system (100) as claimed in claim 1, wherein said sensor (106) are arranged on a Printed circuit board (PCB) in a linear fashion.

6. The system (100) as claimed in claim 1, wherein said sensors (106) are installed in a way to form a matrix-type structure.

7. The system (100) as claimed in claim 1 further comprises a sensor detection module configured to detect the type of said sensor based on its measurement range, accuracy, resolution, and other electrical parameters pertinent to its operating range.

8. The system (100) as claimed in claim 1 employs a contact-based process to determine the surface undulations.

9. The system (100) as claimed in claim 1, wherein said sensor also detects the surface undulations via non-contact measurement process.

10. The system (100) as claimed in claim 1 is a handheld or portable measurementapparatus.

11. A method for measuring flatness and warpage of a surface (108), said method comprising the following steps: placing a measurement system (100) against the surface (108) to determine flatness and warpage; generating at least a signal from at least a sensor (106), said signal is proportional to the warpage depth detected by said sensor (106); processing said signal in a signal processing module (110), the signal is received as a voltage signal from at least the sensor (106), wherein signal processing module (110) evaluates the data pertaining to the surface warpage in response to the signal received from said sensor (106); transmitting said processed signal to a display module (102) of the measurement apparatus or system (100); displaying the measured flatness and warpage in at least one parameter corresponding to the generated signal, via the display module (102); and storing the measured flatness and warpage in a storage module (114).

12. The method as claimed in claim 11 further comprising: detecting a type of said sensor (106) via a sensor detection module provided within the measurement system (100).

13. The method as claimed in claim 11, wherein said sensor (106) is selected from a group of linear position measurement sensors.

14. The method as claimed in claim 11, wherein said sensor (106) comprises Spring return Miniature Linear Potentiometers, Diffuse type Laser Photoelectric Sensors, Time-of-Flight (ToF) sensors, Linear Variable Differential Transformer (LVDTs), Infra-Red Transceivers, Ultrasonic Transducers, LED-Photodiode array.

15. The method as claimed in claim 11, wherein said measurement system (100) may contact the surface (108) or provided at a distant from the surface (108), depending on the type of said at least sensor (106).

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