Patent Abstract:
The present invention includes a device and method for more particularly evaluating the compaction of soil by automating the use of a prior art dynamic cone penetrometer such that user error and error caused by field conditions are eliminated. Recordation of penetrometer data previously not recorded is made more precise by the present invention such that standardized measurement results. The device further includes means for facilitating the determination of compaction of soils through keyhole openings and a means for automating the collection and processing of the generated compaction data.

Full Description:
REFERENCE TO RELATED APPLICATION  
       [0001]     This application is related to U.S. Provisional Patent Application Ser. No. 60/749,863 filed Dec. 13, 2005 entitled “Automation Of Testing, Recording, And Determination Of Acceptable Status Utilizing A Dynamic Cone Penetrometer (DCP)”, the entirety of which is incorporated as if set forth in its entirety herein. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     Penetrometers and related devices have been used for a variety of geotechnical engineering purposes over the years. Among the well-known types of penetrometers is the utility dynamic cone penetrometer (“DCP”) which is commonly used by utility companies to determine the adequacy and degree of soil compaction in restorations of openings made in roadways or other land features for the purpose of installing or maintaining underground facilities. Other types of DCPs are also presently known to be used in evaluating parameters in addition to soil compaction, including for example resistance to penetration or shear strength.  
         [0003]     Generally, DCPs consist of an elongated shaft having a first and second flange spaced a standardized distance apart with a standardized drop weight conveyed freely there-between on the shaft. The DCP further has a conically shaped tip that is driven into the soil by means of the drop weight being lifted to the height of the first flange and then dropped onto the anvil, or second flange, attached to the shaft. Typically, the drop weight of most DCPs has a standardized mass and a standardized range of movement along the shaft, and thus the driving energy caused by the drop weight striking the anvil is also standardized. In common usage, the operator of the DCP will position the tip of the penetrometer on a soil to be evaluated and with one hand will raise the weight up to the first flange, which is located below a handle provided for steadying the device with the other hand. The weight is then released and permitted to fall freely by gravity. The driving energy generated by the weight hitting the anvil causes the tip of the DCP to move in a downward direction into the soil. Generally, the process of raising and releasing the weight to strike the anvil will be repeated until a standard depth of penetration is established. At that time a record is made of the number of times the anvil has been raised and dropped, as an indication of the relative compactness of the soil. If the required blowcount is reached before the standard penetration is reached, this automatically means a passing condition, and further blows are unnecessary, and not usually pursued.  
         [0004]     The utility DCP is usually used in a go/no-go fashion, in which the number of blows by the drop weight to the anvil to achieve a standard depth of penetration is compared with a predetermined standard: if the number of blows equals or exceeds the standard, the compaction of the soil is deemed adequate. If the number of blows, however, does not meet or exceed the predetermined standard, additional compaction of the soil is performed until the standard is met. Certain soils may require a different criterion; one such is poorly-graded sand, for which the blow-count is determined for a greater depth of penetration, and thus one or more additional gradation lines can be provided on the shaft near the tip to assist in determining appropriate compaction.  
         [0005]     DCPs are generally manual testing devices, relying exclusively on the ability of the user to record test results. Automation approaches by others in the field of soil testing, involve the use of some electronic measuring assemblies attached to the DCP. One such implementation involves a linear variable differential transformer sensor (e.g., an LVDT sensor) that extends from the DCP to the soil. Another implementation, by Applied Research Associates, Inc. (“ARA”) (marketed by Vertek as a Data Acquisition System (“DAS”)), features a portable DAS that utilizes a string potentiometer attached to a hook on the DCP rod anvil in such a way as to monitor the DCP penetration. These presently known automated approaches however are generally cumbersome and fragile and further lack the ability to readily transmit data collected by the DCP to remote data-logging and display devices, such as portable computers or personal digital assistants (“PDAs”) for secure logging and retention of data. Existing automated approaches are also generally unable to effectively display the collected data in real-time or transmit the data by means of wireless transmitters.  
         [0006]     Accordingly, there is a need for an automated device and method to relieve a user of a DCP from the arduous task of keeping track of data manually. It would thus be advantageous to have a device to alleviate the need for the user to manually measure the distance that the DCP has moved during a particular evaluation, and further that would free the user from having to manually count the number of times that the drop weight strikes the anvil. It would additionally be advantageous if such an innovation could determine whether the drop weight of the DCP has been raised to an appropriate position before being released in order to generate the standardized driving force. Such an innovation would ensure that the evaluation being carried out by the DCP is proper and would alert the user when certain drops of the weight were invalid and require repetition of the test. Use of such an automated device and method in connection with a DCP would lessen the likelihood of user error and thus provide a more accurate and reliable assessment of the compaction of soil being evaluated. An automated device and method of collecting data generated by a DCP would further provide a more permanent, secure and tamper-proof record for test data, including, but not limited to, data concerning site location, soil description, lift thickness, and blowcount and depth of penetration patterns.  
         [0007]     Another difficulty in determining soil compaction (and/or other soil properties) is posed by the smaller openings, such as keyhole openings, that have begun to be used by utility companies, and others, in operations that require installation or repair of underground equipment or settings. Keyhole openings are typically smaller than 18-inches in diameter (when circular) or on a side (when rectangular). These openings have become feasible due to the development of tools allowing work to be performed on underground facilities from the surface through tight or enclosed spaces. As operators cannot physically enter such openings, compaction and verification of soil at the bottom of the opening must be performed from the surface above and outside of the so called “keyhole”. The DCPs of the prior art as presently configured cannot be used for this purpose as readings are almost impossible to be made with any accuracy due to the limited sight lines available.  
         [0008]     Accordingly, it would also be desirable to have a device and method to enable use of a DCP in a keyhole or in other applications in which a DCP is to be used to evaluate soil at the bottom of a small opening. It would be further advantageous for such a device and method to be automated in order to simplify the collection, recordation, monitoring and transmission of compaction data generated by the DCP so that it can be evaluated in real-time by the user and others from a remote location, and so that the data can be transferred to and stored at a centralized database for comprehensive record keeping, or transmission to others for analysis.  
       SUMMARY OF THE INVENTION  
       [0009]     In one embodiment of the present invention, an automated device for processing soil compaction data generated by a dynamic cone penetrometer (“DCP”) is provided. The automated device features a sensor assembly having a distance sensing means, data acquisition means, and a transmitter. The device further includes a display device, a recording device, and a receiver for receiving data from the transmitter. A processing device in communication with the receiver is further provided for processing the data communicated to the receiver and to communicate the processed data to the recording device and the display device.  
         [0010]     In this embodiment, the distance sensing means can be an optical or ultrasonic distance sensor and the processing device can be a handheld computer, a laptop computer, a cell phone or a personal digital assistant (PDA). Further, the transmitter of the automated device can be a radio frequency transmitter, an infrared light transmitter, a Bluetooth signal transmitter or other short range telemetry protocol transmitter.  
         [0011]     Another embodiment of the present invention is directed to a DCP for automated evaluation of soil compaction. In this embodiment, the DCP features an elongated shaft having a first end with a flange and a handle adjacent to the flange and a second end comprising a tip. The elongated shaft may further feature a graduated area having one or more horizontal markings positioned in generally vertical alignment to one another along the length of the shaft near the tip. The flange of the DCP extends in a direction perpendicular to the elongated shaft and an anvil is fixedly mounted between the first and second ends of the elongated shaft. The DCP also features a drop weight slideably mounted to the elongated shaft such that the weight is moveable along the shaft between the flange and the anvil. In this embodiment, an automated device for collecting and processing compaction data from the DCP is also featured. Like the previously described embodiment, the automated device can comprise a sensor assembly having a distance sensing means, data acquisition means, and a transmitter. The device further includes a display device, a recording device, and a receiver for receiving data from the transmitter. A processing device in communication with the receiver is further provided for processing the data communicated to the receiver and to communicate the processed data to the recording device and the display device.  
         [0012]     The DCP of this embodiment can further include an automated system for detecting when the drop weight has been raised into an upper position above the anvil. This system features a weight detection assembly positioned between the first end of the DCP and the anvil and a remote operator assembly having a receiver and an electronic processing device. The detection assembly of the system can further have a detector and transmission element tuned to receive and process compaction data. When the drop weight of the DCP is raised into the upper position, the detector is actuated in a manner which generates a signal that is broadcast by the transmission element to the receiver of the remote operator assembly. The receiver can be adapted to receive the signal broadcast from the transmission element and to transfer the signal to the electronic processing device for processing, display or recording.  
         [0013]     In this embodiment, the detector of the weight detection assembly comprises a switch that is actuated when the drop weight is raised into the upper position. The switch can be an optical distance sensor, an ultrasonic proximity switch or a physically or electrically actuated sensor. Alternatively, if the drop weight of the DCP comprises a magnetic field, the detection assembly can be an inductive sensor that detects when the weight is in the upper position by detecting the magnetic field.  
         [0014]     Another embodiment of the present invention is directed to a DCP for automated evaluation of soil compaction through a keyhole type opening. In this embodiment, a DCP is provided having general features consistent with the DCP of the previous embodiment. The DCP of this embodiment further includes an adjustable collar adapted to fasten around the elongated shaft. The collar is movable on the shaft between the anvil and tip and can have cooperative graduations of comparable dimension to the height of the tip and also the markings of the graduated area on the elongated shaft near the tip. The cooperative graduations of the adjustable collar enable an operator to manually determine how deep the DCP has moved into the soil from outside the keyhole opening by enabling the operator to visually read the graduations against an apparatus placed horizontally across the top of the keyhole opening.  
         [0015]     The DCP of this embodiment can also include at least one elongated shaft extension unit having a first and second ends that are both capable of fastening to the second end of the elongated shaft, the tip, or the first or second ends of another extension unit. The DCP of this embodiment can further be used in connection with a surcharge weight having a top and bottom surface with centrally located openings forming a central cavity that permits the tip and elongated shaft or a shaft extension unit to extend through the weight. An automated device for collecting and processing compaction data from the DCP can further be included in this embodiment, as can an automated system for detecting when the drop weight has been raised into an upper position above the anvil.  
         [0016]     An automated method to collect, record and monitor compaction data generated by a DCP is further provided by one embodiment of the present invention. This method features placing a sensor assembly having an optical distance sensor and transmitter at a fixed position on a soil surface to be evaluated by the DCP. The DCP having a sensor target mounted to the elongated shaft is positioned such that the target is aligned with the assembly in a vertical plane. The distance between the sensor and the target is then detected and streamed as an electronic signal from the transmitter to a receiver mounted to a remote electronic processing device. The streamed signal from the transmitter can then be monitored as a value in real-time at the remote processing device such that the value remains constant where the distance between the sensor and the target does not change. The drop weight affixed to the penetrometer is then raised from a first position adjacent to the anvil to a predetermined second position above the anvil and then is released and permitted to fall under the force of gravity in a direction towards the anvil until the weight contacts the anvil. The contact generated by the weight striking the anvil generates a force that causes the penetrometer to move in a downward direction into the ground surface to be evaluated such that the distance between the target and sensor decreases. When this occurs, the value monitored by the remote processing device changes such that a new value is constantly displayed which corresponds to the new distance between the sensor and the target. The number of times that the value changes is then registered as the number of times that the weight strikes the anvil. The distance that the penetrometer moves after each blow by the anvil is recorded, as is the cumulative distance that the penetrometer has moved during the evaluation. This distance data provides a permanent record which can be viewed by the user or others so that the success or failure of the compaction evaluation can be determined.  
         [0017]     In another embodiment of the present invention, an automated method is provided for detecting when the drop weight has been raised to an appropriate position along the shaft of the DCP. In this method the drop weight of the DCP is raised from a first position adjacent to the anvil to a predetermined second position above the anvil, such that when raised into the second position, the drop weight is in closer proximity to the top flange of the penetrometer. The presence of the drop weight in the second position is detected by a weight detection assembly and an electronic signal indicating that the weight is present in the predetermined second position is generated. The electronic signal is transmitted to a reception element of a remote electronic processing device where a signal, such as for example an audible tone, can be generated in order to alert the user that the weight has been lifted into the second position. The drop weight is then released from the second position above the anvil and permitted to fall under the force of gravity in a direction towards the anvil. The absence of the drop weight in the second position is detected and an electronic signal is generated and transmitted upon release of the weight from the second position.  
         [0018]     Another embodiment of the present invention is directed to a method of using a DCP to evaluate the compaction of soil through a keyhole type opening having an open top. In this method an apparatus having a top and bottom surface is placed across the open top of the keyhole opening. An adjustable collar is affixed to the elongated shaft in a position between the anvil and the tip. The DCP, possibly having one or more shaft extension units to match the height of device to the depth of the keyhole, is then positioned in the keyhole such that the tip of the DCP is resting on the soil surface at the bottom of the keyhole or is buried in the soil to a predetermined initial depth. The collar is then adjusted along the elongated shaft such that its cooperative graduated area can be read against the top surface of the apparatus spanning the opening of the keyhole. The drop weight affixed to the penetrometer is then raised from a first position adjacent to the anvil to a predetermined second position above the anvil and then released and permitted to fall under the force of gravity in a direction towards the anvil. A measurement is then taken to determine how much the DCP moved into the soil.  
         [0019]     While the device and methods of the present invention are ordinary used in connection with evaluations for determining the compaction of various types of soil, persons having ordinary skill in the art will understand that each of the embodiments described herein may be used for alternative purposes, including for example evaluating resistance to penetration or shear strength, without departing from the novel scope of the present invention.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0020]      FIG. 1  is an elevational view of a Dynamic Cone Penetrometer (“DCP”) of the prior art.  
         [0021]      FIG. 2  is an elevational view of one embodiment of a device made in accordance with the teachings of the present invention, including a sensor assembly for automatically collecting, transferring and monitoring data generated by a DCP.  
         [0022]      FIG. 2A  is a top perspective view of one type of sensor assembly of a type shown in  FIG. 2 .  
         [0023]      FIG. 2B  is an elevational view of an alternative embodiment of a device made in accordance with the teachings of the present invention.  
         [0024]      FIG. 3  is an elevational view of another embodiment of a device made in accordance with the teachings of the present invention; showing the use of a DCP in a “keyhole” application.  
         [0025]      FIG. 4  is an elevational view of a further embodiment of a device made in accordance with the teachings of the present invention showing a device and method for placing and retrieving a surcharge weight and/or sensor assembly from the bottom of a keyhole when the device is used in connection with the embodiment demonstrated in  FIG. 3 .  
         [0026]      FIG. 5  is an elevational view of a further embodiment of a device made in accordance with the teachings of the present invention, showing a DCP used in a keyhole application together with an automated device and method where a sensor assembly is placed outside a keyhole opening.  
         [0027]      FIG. 6  is an elevational view of a further embodiment of a device made in accordance with the teachings of the present invention featuring the use of a DCP in a keyhole application together with an automated sensor assembly located within a keyhole opening.  
         [0028]      FIG. 7  is an elevational view of another embodiment of a device made in accordance with the teachings of the present invention featuring the use of a DCP in a keyhole application together with an automated sensor assembly.  
         [0029]      FIG. 7A  is a close-up broken elevational view of an insert for placing or retrieving the sensor assembly and/or surcharge weight form a keyhole opening.  
         [0030]      FIG. 8  is a cut-away elevational view showing an automated weight-position detection assembly of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0031]     While the present invention is susceptible of embodiment in various forms, there is shown in the drawings a number of presently preferred embodiments that are discussed in greater detail hereafter. It should be understood that the present disclosure is to be considered as an exemplification of the present invention, and is not intended to limit the invention to the specific embodiments illustrated. It should be further understood that the title of this section of this application (“Detailed Description of the Invention”) relates to a requirement of the United States Patent Office, and should not be found to limit the subject matter disclosed herein.  
         [0032]      FIG. 1  shows a dynamic cone penetrometer (“DCP”)  1  having general characteristics in accordance with the teachings of the prior art. Persons having ordinary skill in the art will understand the basic operations of such a device; however, briefly, the tip  2  of the device is generally placed onto the surface of soil “S” whose compaction is to be tested. A weight  3  is raised from the flange, or anvil,  4  on which it rests, up to an upper flange  5  and allowed to drop to its first at rest position. The dropping of the weight causes the cone  2  to penetrate the surface of the soil S. This operation is repeated until the tip  2 , and attached shaft  6 , penetrate the soil to a marked level (such as, for example, as graduated  7  or  8  on the shaft depending on the type of soil being evaluated). The number of drops of the weight to reach this level is recorded and serves as an indication of the compactness of the soil.  
         [0033]     In  FIG. 2 , an embodiment of the present invention designed to automatically collect, transfer and monitor the data generated by a DCP  10  is provided. As shown in  FIG. 2 , the DCP  10  features an elongated shaft  20  with a handle  21  and flange  22  at one end, and a conically shaped tip  23  at the other end. It will be understood by persons having ordinary skill in the art that while the various parts shown have been described and illustrated as having certain shapes, the actual shapes of the parts, such as “conical”, are merely given for ease of understanding, and that various shapes, sizes and proportions can be interchanged without departing from the novel scope of the present invention. For example, the tip of the device can have any shape that advantageously permits the end of the DCP to penetrate the soil while working, such shapes as generally triangular and others can be substituted therefore.  
         [0034]     The handle  21 , in the illustrative embodiment, is located adjacent to a flange  22  and extends generally perpendicularly about shaft  20 . The DCP  10  also has an anvil  24  and drop weight  25 , having a standardized mass, mounted so that it can ride freely along shaft  20 . The drop weight  25  is slideably mounted to the elongated shaft  20  in a manner that allows the weight  25  to be manually or mechanically raised from a lower position adjacent to the anvil  24  to an upper position proximate to the handle  21 .  
         [0035]     In the present embodiment, the elongated shaft  20  may also have a graduated area  26  to permit the measurement of the depth-of-penetration that is achieved once the tip  23  is driven into the ground surface “S” to be evaluated. The graduated area  26  can feature one or more horizontal markings  27  positioned in generally vertical alignment along the length of the shaft  20  proximate to the conically shaped tip  23 . In normal “go/no go” operation of the DCP, the user is generally interested in determining whether a standard depth of penetration can be achieved by at least a required number of blows by the drop weight. The markings  27  of the graduated area  26  correspond to standard penetration depths of various soil types and are thus provided along the shaft in order to assist the user in determining when a standard depth of penetration has been achieved.  
         [0036]     In use, the DCP  10  of the present embodiment is positioned such that the tip  23  is placed on the ground surface S to be evaluated. Often the initial position of the tip  23  for evaluation is such that the end of the tip adjacent to the shaft  20  is flush with the soil S. This position is usually achieved by initially tapping the weight  25  against the anvil  24  until the tip  23  is sufficiently buried in the soil S. After being raised to the desired upper position, drop weight  25  is released and permitted to fall onto anvil  24 . As will be understood by persons having ordinary skill in the art, the contact between the drop weight  25  and the anvil  24  generates a standardized force that causes DCP  10  to move in a downward direction into the ground surface S to be evaluated. In the present embodiment however, the DCP  10  also features an automated method and device for recording and collecting data generated by this action. As shown in  FIGS. 2 and 2   a , the device of the present invention includes a sensor target  30  mounted to the elongated shaft  20  between the anvil  24  and the conically shaped tip  23 , a remote operator assembly  40 , and a sensor assembly  31  mounted within a housing  32 , having a centrally located opening  33  to enable the tip  23  of the DCP  10  to pass through the housing  32  and contact the soil surface S. The present embodiment can additionally feature a surcharge weight  55  that can be incorporated in housing  32  or be a separate item with an opening in approximate vertical alignment with the opening  33  of the housing  32 .  
         [0037]     In the operation of the device of the present embodiment, a weight  25  is raised and dropped onto the anvil  24  of the penetrometer as described above, with respect to the prior art. The sensor  34  records the distance that the DCP  10  is driven into the ground surface S each time the drop weight  25  contacts the anvil  24 , and also measures the cumulative distance that the DCP  10  travels into the ground surface S, during a particular evaluation. The automated data collection method and device of the present invention includes means to collect the distance measurements as well as the number of times the weight  25  strikes the anvil  24 , and also features means to broadcast the data collected to a desired receptor. In operation, therefore, as the penetrometer is used, the sensor  34  collects the measurements as data and then broadcasts the data as an electronic signal to the remote operator assembly  40  for information presentation and results recording.  
         [0038]     It will be seen that the device of the present invention automates the process of independently documenting the number of blows to travel a known distance (instead of relying on the memory of the user). The device further provides additional important and useful information to the user which has previously been unavailable, such as the actual distance traveled per blow (review of which may help to identify uniformity of soil compaction, for example). The device can provide information that can help to independently identify whether a particular soil spot has been compacted to an acceptable level (passes) or not (fails the test). Use of the device can automate the recording of the details of tests providing specific detailed information for an entire construction site or over any operational area covered by a utility or its contractors, for example. Since the data collected by the present invention can be transmitted to a remote display device and can be uploaded, immediately or later, to a computer in a central facility for recording in a database, the results of soil evaluations conducted by the DCP can be made available to more people in less time. Thus personnel working a particular project will be more informed about the condition of soil being evaluated and will be able to make quicker and more informed decisions as to how work on the project should proceed.  
         [0039]     In embodiments of the device of the present invention, an independent time/date stamp for each test can be provided. Further, to insure accuracy, embodiments of the device can be made such that the operator has a limited ability to interfere with or modify test results. The device of these embodiments can therefore limit the interaction of the operator with data collected to thereby better insure that the test details cannot be modified, either purposely or incidentally. In addition, the present embodiment can measure the time that it takes for the drop weight  25  to fall from the raised position to contact the anvil  24  in order to verify that the weight was raised to an appropriate height and that the fall of the weight  25  was unimpeded.  
         [0040]     In some embodiments, the sensor  34  can measure the distance that the tip of the DCP travels into the soil, without being in physical contact with the DCP during operation. Such a system can advantageously protect the sensor device from exposure to the elements, and also the particularly the harsh conditions at a test or construction site. Previous attempts at independent or alternative measurement techniques, in the prior art, have involved equipment requiring actual physical connection or attachment to the DCP. Such prior art devices, as will be understood, are often subjected to harsh conditions permitting devices to bend, break or be otherwise damaged, causing diminution in accuracy or delay in completion of tests.  
         [0041]     As shown in  FIG. 2 , the sensor assembly  31  features a transmitter that can relay data and other information about the test to a cooperative unit, such as a receiving unit  40  which is capable of interaction and/or communication with the operator or a computer. In a preferred embodiment, such communication or interaction is accomplished without using wires or other physical communication means that are prone to breakage and are often difficult to use without entanglement.  
         [0042]     It will be understood by persons having ordinary skill in the art that the utilization of a non-contact device and method for incremental and overall distance measurement can eliminate the problems occurring due to having equipment exposed to the impacts and vibrations inherent in the dropping of a weight and its jarring contact with the anvil. The added benefits of automatic recordation of the details of tests, without operator access, provides a more independent verification of the performance of the test and its results.  
         [0043]     The illustrated embodiments also have many benefits over prior systems including: electronic recordation of the cumulative penetration depth and the depth of the DCP after each blow by the drop weight  25 ; systematic recordation of the number of blows by the drop weight; time-stamping of data records; independent verification of data through software algorithms of associated handheld computing devices; and isolation of recordation devices to protect them from vibrations resulting from the drop weight of the DCP.  
         [0044]     It will be seen in  FIG. 2  that there are primarily three main components to the automated device of the present embodiment. The first component, as shown in  FIG. 2A , is the sensor assembly  31  which consists of: an optical distance sensor  34  having a light source  38  and sensing means  39 ; data acquisition circuitry  35 ; a wireless transmitter  36  and a power supply  37 . The sensor assembly  31  is mounted in a housing  32  that has a centrally located opening  33  to permit the shaft  20  and tip  23  of the DCP  10  to pass through the housing  32  and contact the soil S. As shown in  FIG. 2 , the housing  32  is placed directly on the soil to be evaluated.  
         [0045]     The second main component of the automated device is a remote operator assembly  40 . The remote operator assembly  40  consists of a wireless receiver  41  and an electronic processing device  42 , such as a handheld computer or personal data assistant (“PDA”). It will be understood by persons having ordinary skill in the art that any manner of data collection and possessing device can be used here, without departing from the novel scope of the present invention. The wireless receiver  41 , as illustrated, can record the incremental blowcount and distance information transmitted to it from the wireless transmitter  36  of the sensor assembly  31  and forward the information to a processing device  42 . The processing device  42  can include means to present some or all information to the user of the device, such that the efficacy of the test can be determined periodically such that necessary changes or adjustments to the test can be made. The processing device  42  further serves as a data recorder for storing information for observation and reporting purposes. Alternative processing devices such as laptops computers or smart phones having electronic processors, storage units and display screens can alternatively, or additionally, serve as the processing device  42  without departing from the novel scope of the present invention. In addition, alternative means of communications between the sensor assembly  31  and the remote operator assembly  40  can be utilized without departing from the novel scope of the present invention. For example, Bluetooth technology, other short distance telemetry protocols, infrared transmitting and reading devices are contemplated for use in the device and method of the present invention. Further, other technological measuring means, including for example global positioning satellite systems (“GPS”), can be substituted or added to the device of the present embodiment without departing from the novel scope of the present invention. Such GPS systems can provide independent verification of the location of a particular job or soil evaluation and can additionally be used to verify the elevation of the drop weight or DCP in relation to the ground surface.  
         [0046]     The third main component of the automated device of the embodiment shown in  FIG. 2  is a sensor target  30 , which in a preferred embodiment can be mounted to the shaft  20  of the DCP  10 . While the sensor target illustrated in  FIG. 2  is shown in one particular position on the shaft  20 , those having ordinary skill in the art will understand that the target can be positioned in a number of different locations along the shaft  20  and can be adjustably fastened to the shaft by utilizing, for example, an adjustable collar having a locking pin, bolt or screw. The sensor target  30  allows the sensor  34  to determine the distance that the DCP  10  has traveled by measuring the distance between the sensor  34  and the target  30 . In an alternative embodiment, as shown if  FIG. 2B , a sensor  34  having, for example, a laser light source, can be employed to emit a narrow beam of concentrated light in the direction of the anvil  24 , in a manner that enables the light to reflect off of the bottom surface of the anvil  24 , and return to be read by a sensing means  39  configured to read and evaluate such light measurements. In this embodiment, use of the sensor target  30  is unnecessary because a laser light source is of sufficient intensity to be detected by the sensor  34 , after being directed at the more non-reflective bottom surface of the anvil  24 . A sensor target  30  may however be used in connection with the embodiment illustrated in  FIG. 2B  without departing from the scope of the present invention.  
         [0047]     The present invention additionally provides a method of using the automated device in connection with a DCP  10 . Such a method includes placing the housing  32  having the sensor assembly  31  at a fixed position on the ground surface S that is to be evaluated; positioning a DCP  10  having a sensor target  30  mounted to the elongated shaft  20 , such that the target  30  is above the sensor  34 ; and aligning the sensor  34  in a vertical plane such that the sensor target  30  can be seen by the sensor  34 . The initial vertical position of the DCP  10  can then be measured by detecting the distance between the sensor  34  and the target  30 . This distance data is streamed, as an electronic signal, from the wireless transmitter  36  to the wireless receiver  41  mounted to the remote operator assembly  40 . The electronic processing device  42  then monitors the signal as a value, in real-time, such that the value remains constant where the distance between the sensor  34  and the target  30  does not change. The actual test is then carried out with the DCP  10  by raising the drop weight  25  from a first position adjacent to the anvil  24  to a predetermined second position above the anvil  24  and then releasing the drop weight  25  from the second position to allow the weight to fall to the anvil  24 . The contact of the weight  25  with the anvil  24  generates a standardized force that causes the penetrometer to move in a downward direction into the soil such that the distance between the target  30  and sensor  34  decreases. Optical sensor  34  then detects the new distance between it and the target  30 ; and data indicating the new distance between the two is broadcast by the wireless transmitter  36  to the receiver  41  of the remote operator assembly  40 . The new distance is then transmitted to the electronic processing device  42  where it may be recorded and displayed.  
         [0048]     Changes in the streaming value indicate that a blow has occurred, with the new repeating value representing the next distance; the difference between the new value and the previous value is the distance traveled resulting from the blow. By monitoring the total distance traveled by the DCP  10  and the number of blows made, the soil compaction can be determined. Determination can be made in at least one of two ways. First, by counting the total number of blows to travel a known distance, and comparing the number with the minimum required number for adequate soil compacting. Alternatively, the number of blows can be counted until the minimum required number is reached, and comparing the actual traveled distance to a known distance; a passing result occurring if the actual distance is less than the known distance. In addition, other soil properties may be inferred from a continuous record of blowcount versus penetration.  
         [0049]      FIG. 3  illustrates an alternative embodiment of the present invention, which is intended to enable a DCP  10  to be used to evaluate the compaction of a ground surface S at the bottom of a keyhole opening  50 , or other type of small excavations, where a remote reading from the surface is necessary or desired. The present invention features a DCP  10  having general characteristics as described above, in combination with additional components such as an adjustable collar  51  and/or shaft extension unit  52 . As shown in  FIG. 3 , the adjustable collar  51  of this embodiment is adapted to fasten around the elongated shaft  20  of the DCP  10  between the anvil  24  and the second end of the shaft  20 . Once a correct position for the collar  51  is determined, it may be fastened to the elongated shaft  20  in a fixed position by means of a locking pin, bolt or screw  53  such that the collar  51  will not slide down the shaft  20  when the drop weight  25  contacts the anvil  24  during the evaluation. The collar  51  can additionally feature cooperative graduations of comparable dimension to the markings of the graduated area on the elongated shaft near the tip.  
         [0050]     In order to match the DCP  10  of this embodiment to the depth of the keyhole opening  50 , the DCP  10  may additionally include one or more shaft extension units  52  that are capable of being fastened to one another at their ends or alternatively to the elongated shaft  20  or the conically shaped tip  23 . When the appropriate number of shaft extension units  52  are used, it is intended that the DCP  10  will extend outside the opening of the keyhole  50  to such an extent that the adjustable collar  51  can be positioned in a manner that enables a portion of the collar to be in generally horizontal alignment with the opening of the keyhole  50 . When this is accomplished, a bar, plate, or other apparatus  54  having a flat surface, can be placed across the top opening of the keyhole  50 , such that the cooperative graduations of the collar  51  can be read against the top surface of the apparatus  54  spanning the opening. For convenience, the apparatus  54  spanning the keyhole  50  can be perforated to allow the DCP  10  to pass through it; or alternatively, can be positioned adjacent to the DCP  10  such that readings can be taken against the edge of the apparatus  54 . This embodiment can further feature the use of a surcharge weight  55  to assist with the evaluation of compaction of the soil S. The surcharge weight  55  can be part of housing  32  or may be a separate component that can be fastened to the housing  32  or merely used on its own. In use, the surcharge weight  55  can be placed directly on soil S so that a single depth of penetration may be sufficient for more soil types, and a single blow-count criterion may likewise be made more nearly universal. As shown in  FIG. 3 , the surcharge weight features a centrally located opening  39  so that the shaft  20  and tip  23  of the DCP  10  are able to pass through the weight  55  and contact the soil S.  
         [0051]     Referring now to  FIG. 4 , a device and method of another embodiment of the present invention is shown for enabling a surcharge weight  55  to be placed or retrieved from the bottom of a keyhole opening  50 . In this embodiment, flexible cables  56  of an appropriate length are used to attach the weight  55  to the penetrometer (for instance to the bottom of the anvil), so that the weight  55  hangs slightly below the tip  23 . The cables  56  can be adjusted for various shaft lengths provided by the extensions described earlier. Once the surcharge  55  rests on the surface, further descent of the DCP  10  into the soil will result in slacking of the cables  56 , and thus prevent interference with the DCP  10  operation. Upon completion of the test, withdrawal of the DCP  10  will automatically result in simultaneous retrieval of the surcharge weight  55 . It will be further understood by a person having ordinary skill in the art that other connectors can be used instead of cables  56  without departing from the novel scope of the present invention.  
         [0052]      FIG. 5  illustrates a further embodiment of the present invention featuring the use of DCP  10  in a keyhole application in combination with an automated method and device for recording and collecting data generated by the penetrometer. In this embodiment, the housing  32 , having a sensor assembly  31 , is positioned on top of an apparatus  54  that spans the open top of the keyhole  50 . It will be seen that housing  32  can be placed either directly on top of apparatus  54  or on the top of a surcharge weight  55  positioned on top of apparatus  54 . In this embodiment, an additional surcharge weight  55  can also be positioned on the ground surface S, at the bottom of the keyhole opening  50 .  
         [0053]     In operation of the embodiment shown in  FIG. 5 , the user of the DCP  10  positions the adjustable collar  51  such that the cooperative graduations  59  are in general horizontal alignment with the top surface of sensor assembly  31 . Once this initial condition is established, the operator may then begin the evaluation process by raising and releasing the drop weight  25 . While use of the automated data collection device and method of the present embodiment can enable the user of the DCP  10  to collect or evaluate the results of a particular test in full automatic mode, the location of the cooperative graduations  59  on the adjustable collar  51  makes it easy for visual verification to be manually performed as well. In addition, while the reflector plate  30  illustrated in  FIG. 5  is shown to be mounted directly to the adjustable collar  51 , this is just one possibility, and those persons having ordinary skill in the art will understand that the reflector plate  30  could be mounted to the DCP  10  without being fastened to the collar  51  without departing from the novel scope of the present invention.  
         [0054]      FIGS. 6 and 7  illustrate additional embodiments of the present invention featuring a DCP  10  used in a keyhole application where the sensor assembly  31  is positioned within the keyhole  50  and proximate to the ground surface S. As shown in  FIGS. 6 and 7 , a housing  32  having a sensor assembly  31  can be positioned directly on the soil surface S or can instead be positioned on the top of a surcharge weight  55  positioned on surface S.  FIG. 6  additionally shows a device and method for remote placement and retrieval of the housing  32  and/or surcharge weight  55 , similar to those previously described for remote placement and retrieval of the surcharge weight  55  (See  FIG. 4 ). In  FIG. 6 , the sensor target  30  is fixed to the shaft  20 , or a shaft extension unit  52 , at a suitable height above the tip  23 . At least one flexible connector  56  attaches the housing  32  (and surcharge weight  55  if appropriate) to the sensor target  30 , such that the withdrawal of the DCP  10  from the keyhole  50  will automatically result in simultaneous retrieval of the sensor assembly  31  (and surcharge weight  55  if used). The sensor target  30  thus acts as a point of attachment for the automated device  31  and surcharge weight  55 .  
         [0055]     An alternative method for remote lowering and retrieval of the sensor assembly  31  and/or surcharge weight  55  is shown in  FIGS. 7 and 7 A. In this embodiment a flange  57  or insert  58  is fastened to the housing  32  having the sensor assembly  31 . The flange  57  and insert  58  are sized to allow free passage of the shaft  20  or shaft extension unit  52 , but not the tip  23 . Such an arrangement will need to take account of whether the combined height of the housing  31  and surcharge weight  55  is greater or less than the height of the tip  23 . In circumstances where the tip  23  has a greater height than the housing  31 , as shown in  FIG. 7A , an insert  58  can be affixed to the flange  57 , in order to accommodate for the height differential. The embodiment illustrated in  FIGS. 7 and 7 A thus permits lowering the sensor assembly  31  and/or surcharge weight  55  to the surface, whereupon normal operation of the DCP  10  can proceed. Upon withdrawal of the DCP  10 , the top of the cone  23  will engage with the flange  57  or insert  58 , resulting in simultaneous retrieval of the sensor assembly  31  and/or surcharge weight  55 .  
         [0056]     Another embodiment of the present invention is featured in  FIG. 8 . In this embodiment an automated device and method is shown for detecting when the drop weight  25  of a DCP  10  has been raised into the correct position before being released to contact the anvil  24 . As shown in  FIG. 8 , the device features a weight detection assembly  60  having a detector  61  and transmission element  62 , and a remote operator assembly  40  having a receiver  41  and an electronic processing device  42 . While  FIG. 8  shows a the transmission element  62  and receiver  41  to be connected by a flexible wire for transmission of signals to the receiver  41 , it will be understood by those having ordinary skill in the art that wireless transmission may be used to broadcast a signal from the transmission element  62  to the receiver  41  without departing from the novel scope of the present invention.  
         [0057]     As shown in  FIG. 8 , the detection assembly  60  is positioned on the flange  22  of the penetrometer, such that the detector  61  is adapted to sense the presence of the drop weight  25  when the weight is raised to a particular position above the anvil  24 . Once the weight  25  is raised into this position, the detector  61  is actuated and the transmission element  62  broadcasts a signal to the receiver  41  of the remote operator assembly  40 . While it is contemplated that the receiver  41  and electronic processing device  42  of this embodiment are the same as that previously described, a separate receiver  41  and processing device  42  can be used without departing from the spirit or scope of the present invention.  
         [0058]     In the present embodiment, there are a number of different means by which the drop weight  25  can be detected. The first is by physical contact, in which the detector  61  is a switch that is actuated when the weight is raised to a point on the shaft at which the detector is depressed. The switch of the detector  61  may be a momentary electric switch or an optical or ultrasonic-proximity switch that is adapted to sense when the weight  25  is a particular distance away. Alternatively, when the drop weight  25  comprises a magnetic field, the detector  61  can be an inductive sensor that senses when the drop weight  25  is at a particular distance away, by detecting the magnetic field. Such sensing can include, for example, determining the amount of time it takes light or sound energy transmitted by the switch to be reflected off of weight  25 . Further, the use of laser or infra-red technologies can also be employed in connection with this embodiment, without departing from the novel scope of the present invention.  
         [0059]     In the use of the device illustrated in  FIG. 8 , a method is provided for automatically detecting the presence of a drop weight  25  that is mounted to a DCP. The method includes raising the drop weight  25 , from a first position adjacent to the anvil  24  to a second position above the anvil  24 ; detecting the presence of the drop weight  25  in the second position by a weight detection assembly  60 ; generating an electronic signal indicating that the weight  25  is present in the second position; transmitting the electronic signal to a reception element  41 , of a remote operator assembly  40  (having for example an electronic processing device  42 ); releasing the drop weight  25 , from the second position above the anvil  24 , such that the weight  25  is permitted to fall in a direction towards anvil  24 ; and detecting the absence of the drop weight  25  in the second position upon the release of weight  25 . The method can further include timing the fall of the drop weight from the second position to the anvil in order to verify that the weight was raised to its proper elevation on the shaft and that it was not interfered with after being released.  
         [0060]     The present disclosure includes that which is contained in the appended claims, as well as that of the forgoing description. Although, this invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been made only by way of example, and that numerous changes in the details of the elements, compositions and the combination of individual ingredients may be resorted to without departing from the spirit or scope of the invention.

Technology Classification (CPC): 6