Multidisciplinary Senior Design ConferenceKate Gleason College of Engineering

Rochester Institute of Technology (RIT)Rochester, New York 14623

Project Number: P13061Periodontal Measurement Test System

Raymond BoronczykMechanical Engineering Student

Evan LammertseMechanical Engineering Student

Samuel RempElectrical Engineering Student

Yokai RoElectrical Engineering Student

Ryan ShawMechanical Engineering Student

Kristi WeaverMechanical Engineering Student

ABSTRACT The current method for performing the sulcus depth measurement is a painful, inconsistent and lengthy

process. The Perio Alert system seeks to present a more effective, consistent and pain free measurement technique through the use of ultrasound. The design includes a mechanical fixture, a tooth phantom and electronic programming in Labview. The fixture allows an ultrasonic transducer to be moved through five axes to perform the sulcus depth measurement accurately and repeatedly without physically entering the sulcus. The final product can move the transducer through all axes while detecting material interfaces (and therefore changes in material) and storing the data for post-test analysis.

INTRODUCTION Periodontal disease affects over 50% of adults worldwide and is the leading cause of tooth loss. When

periodontal disease has set in, the depth of the gap between the tooth and the gums (also known as the sulcus) has become greater than the baseline of one to three millimeters. Currently, the presence and extent of periodontal disease are determined using an invasive metal probe to measure the sulcus depth as seen in Figure 1 below. This process is time consuming, inconsistent and painful. Therefore, Perio Alert is in the development stages as an attempt to simplify the sulcus depth measurement process while improving its reliability and associated patient comfort. This concept uses an ultrasonic transducer to perform the sulcus depth measurement from outside the patient’s mouth. Implementing this method would allow for a repeatable measurement, thus reducing the amount of error associated with the process, all while creating a more pain-free, hands-off procedure.

Figure 1: Current sulcus depth measurement method

PROCESS AND METHODOLOGYThis project encompasses developing a method for testing a 10 MHz ultrasonic transducer while performing

the sulcus depth measurement. The main objectives of the project can be broken into three categories: the tooth phantom, the mechanical test fixture, and the electrical program.

A tooth phantom must be constructed to facilitate sulcus depth measurements throughout testing. The phantom should be representative of a human tooth with respect to ultrasonic properties. The phantom must allow for the sulcus depth to be varied in a reasonable amount of time.

The mechanical fixture must be capable of holding and maneuvering the transducer and the tooth phantom. All movements must be accurate and repeatable to ensure the measurements are representative of the sulcus and can be performed by multiple users. The test fixture must be compact and easily transported to allow for

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simple integration into an office setting. It should also allow for repairs and adjustments to be performed by untrained personnel, requiring the composition of an instruction manual.

Lastly, a system and/or program must be developed to serve as the user interface for the measurement process. This system should be simple yet effective, leaving little room for user error. It should also provide meaningful feedback so the sulcus depth measurement can be easily interpreted and explained. The system must also be capable of storing the data from each test in a designated location for post-test analysis and comparison to previous results.

The use of an ultrasonic transducer to perform the sulcus depth measurement is a relatively new concept. A pulser/receiver unit is used to transmit a signal from the transducer. When an ultrasonic wave is transmitted from the transducer it passes through materials at varying rates. The rate at which the wave passes through the material is based upon the ultrasonic properties of the material, such as acoustic impedance, density and speed of sound. When the wave encounters a new material, it will bounce back to the pulser/receiver and a voltage can be measured. Theoretically, this voltage could then be combined with distances traveled by the transducer to calculate the depth of the sulcus.

ULTRASONIC TRANSDUCERThe project readiness package (PRP) indicated that a 10 MHz ultrasonic transducer was available for

use, as well as an oscilloscope and a pulser/receiver unit. However, some logistical issues arose and the team became responsible for purchasing a transducer. The team selected a 10 MHz contact probe offered by Olympus. Unfortunately, the team believes that 10 MHz is not a high enough frequency to detect the minute differences present in human tissue surrounding the sulcus. Furthermore, Olympus offers various styles of transducers (i.e. contact, immersion, etc.) that may have performed better for this particular application. However, due to limited time, budget, and knowledge the team was forced to make a selection to avoid losing schedule.

TOOTH PHANTOM Initially, it was assumed that dentin, enamel, gums and bone must be considered for the tooth phantom to

ensure that it closely resembled a human tooth. However, after multiple conversations with experts in the fields of periodontal and ultrasonic studies it was determined that the aforementioned four constituents of human teeth were not all necessary. The enamel need not be considered because when periodontal disease is present the enamel has been worn away. Furthermore, the use of a 10 MHz transducer and an oscilloscope introduce limitations on the data processing. Therefore, the tooth phantom design consists of materials representing dentin, gum tissue and bone.

Once the pertinent features of a human tooth were agreed upon baselines for the ultrasonic properties were determined. This process was difficult as little research has been performed regarding ultrasonic behavior within the mouth. However, after extensive digging, a subject study was found that included 42 adults (36 women and 6 men). The relevant ultrasonic properties include density, speed of sound within the material and acoustic impedance. A summary of the baseline properties used can be found in Table 1 below. Various non-biological materials were then researched in an attempt to find materials that are similar to the baseline human tooth properties, thus satisfying customer needs 8, 9 and 10 (specification 3.1). It was determined that concrete closely resembles the dentin, brick closely resembles mandibular bone and paraffin and polyurethane both closely resemble soft tissue (gums).

One main concern with the materials initially selected was the ability to manipulate them. Ultimately, when ultrasound attempts to pass through bone it is “blocked” or the signal fails to pass through the material and simply bounces back. That being said, to mimic bone the acoustic properties of the material chosen did not necessarily need to be similar to bone, rather a material must be found that will not allow ultrasonic waves to propagate through it. This opened up more options for the bone phantom material, allowing for easier selection and manipulation. Therefore, it was agreed that a square aluminum tube could be used to represent the bone. The gums were still to be modeled using paraffin and the dentin would be represented by concrete.

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Table 1: Relevant ultrasonic properties for material selection

The tooth phantom design can be seen in Figure 4 below. Two options were considered for meeting customer needs 1 and 4 (specification 3.3), the ability to vary the sulcus depth. The first option would require that each phantom be able to vary its own sulcus depth, i.e. the gum phantom would be able to move relative to the dentin phantom, or vice versa. This option could create complications with regard to accuracy and repeatability. The second option was that separate tooth phantoms would be used, each with a different sulcus depth. This option would require some extra fixture design to incorporate multiple tooth phantoms. However, this option helps to satisfy customer needs 1, 3, 4 and 11 (specification 3.2) of being able to vary the sulcus depth in a reasonable amount of time as the fixture simply needs to orient itself to measure the next tooth phantom.

Figure 4: Final tooth phantom design

The final design consideration for the tooth phantom was its interface with the fixture. A plate was incorporated on the bottom of the tooth phantom. The addition of this plate allowed for the tooth phantom/turn table interface to be separate from the tooth phantom itself. This makes for an easy assembly/dis-assembly process that does not involve the tooth phantom materials. Each plate will remain mated to the tooth phantom it is initially paired with. A simple bolt pattern (eight holes) will be machined on the turn table to allow for two bolts to fasten each plate to the turn table. A few options were available for attaching the tooth phantom to the mounting plate; a combination of Scotch Extreme Mounting Tape and JB Weld proved to be the best option as it would not interfere with the turn table (as other options might have).

Initially, the tooth phantom was designed to incorporate a representative sulcus. However, the project scope was redefined to simply require for the detection of material interfaces. Therefore, the presence of a sulcus was not necessary. The aluminum tube was cut into sections and a portion of a credit card was folded around the tube to allow for a flat surface as the concrete formed. The concrete was poured into the tube and leveled off with the credit card foundation. This assembly was then set aside to dry and the credit card was removed. The interface between concrete and aluminum was cleaned up and the gum material was applied.

The formation of the tooth phantom provided some unforeseen difficulties with regard to the soft tissue representation. Initially, paraffin wax was to be cut to the proper shape and size then slid over the square aluminum tube. However, upon attempting to cut the paraffin wax it became evident that the design was too thin for the paraffin to accommodate, as the paraffin simply shaved away. The team tested various materials that could be easily formed and would respond to the ultrasonic probe. Ultimately, two gum phantom materials were selected and tested, rubber and fabric paint.

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Section A

Section B

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MECHANICAL FIXTUREThe mechanical fixture portion of this project is responsible for positioning the ultrasonic transducer to

make contact with the tooth phantom and perform a measurement. Based on customer need 5 (specifications 1.1, 2.1 and 4.1) the system must allow for five axes of movement so that the probe can reach the tooth and possibly perform measurements at various angles. The general design of the positioning system follows the logic of a basic computer numerically controlled (CNC) machine design and can be divided into the following three areas: three linear axes of movement, pitch, and yaw.

The three linear axes of movement involve the lateral, longitudinal, and vertical motions of the system. These axes of movement all utilize ACME lead screws to translate platforms, similar to a lathe, mill or simple CNC machine. Lead screws were integrated into the design since they are both accurate and relatively low priced. The lead screws chosen for this application are 3/8” diameter 303 stainless steel. The vertical application uses a 0.100” pitch screw while the lateral and longitudinal use 0.083” pitch screws. The screws are coupled with anti-backlash nuts made from a low friction lubricated plastic. These screw and nut assemblies mount via steel L brackets to a sliding platform made of Delrin plastic for each of the three axes. These platforms are supported by two ¼” diameter stainless steel guide rods each to remove some loading from the screw. Furthermore, as the name suggests, these rails also guide the platform along a straight line without allowing rotation. To support the small radial loads transmitted to the screw and provide a positive location to limit misalignment with the motor, two small steel ball bearings are used on the non-motor end of the screw. The radial ball bearings are more than capable of withstanding the small axial loads in the system. To keep the design somewhat flexible, simple setscrew collars are used to transmit the axial loads of the screw to the bearings. This allows for the system to be assembled loosely and then tightened down avoiding preloading the screw, housing, or the motor. The motor end of the screw is also turned down to accept a set screw style coupling that links the shaft to the mounted stepper motor. Flats were filed onto the screw shaft to ensure the coupling would transmit the motor torque.

Figure 2: Mechanical fixture

One of the major concerns surrounding the three linear axes of movement was friction. The lead screw pitch and the low friction material of the nut were chosen to amplify the torque of the system and minimize friction. Originally, the plastic sliding platforms were to be directly in contact with the guide rods. After initial assembly, the realistic misalignment of the guide rail bores inside the sliding platform was too great and caused a large amount of friction in the system. To combat this friction and stay within the torque specification of the stepper motors, the tables were fitted with oil impregnated bronze linear bearings. These bearings are pressed slightly into the end of the guide rail bores to limit the amount of surface area in contact with the guide rods and to keep the number of positive locations of components to a minimum. Locating the sliding platforms with the screw mount (L-bracket) and the guide rods can cause misalignment if components were not machined absolutely perfect. To overcome this, the platforms are consistently located using the guide rods, which are intended to carry the load, and then the screw is attached to the L-bracket in its neutral position.

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The next component of movement is the pitch axis. This axis is responsible for mounting the transducer as well as controlling the angular pitch of the transducer using a servo motor. The entire pitch axis assembly is mounted to the vertical sliding platform. The pitch axis consists of three rectangular mounting blocks, a shaft, the probe mounting fixture and the servo motor, as seen in Section A of Figure 2. The probe mounting fixture is pinned to the shaft and then placed between the first two mounting blocks. The shaft continues to the third mounting block, which serves as a mount for the servo motor. Oil impregnated bronze bushings are used to reduce the friction of the system and support the shaft radially.

One important aspect of the pitch axis is the need for the transducer to be replaced with another if needed. Nearly all of the transducers available are very small and have a cable connected to them; therefore, the holding fixture must to be designed specifically for each transducer. A two piece design was selected to minimize the amount of machining required. This assembly can be seen in Section A of Figure 2. The larger probe mounting fixture which is pinned to the shaft is designed to have a channel which the probe holding fixture rides in. The probe holding fixture itself is two small pieces of aluminum that clamp the transducer between them.

A second important feature of the pitch axis is to ensure that contact with the tooth phantom is maintained throughout the test and that the system is not rigid, as stiff contact could damage the probe. To accomplish this, the transducer holding fixture is spring loaded. The channel in the mounting fixture was made longer, and a spring was placed between the back wall of the channel and the aluminum holding fixture. The transducer must have about 3/8” of give to allow for safe contact. One hurdle that was encountered was the need to have a stop built in to the travel so that the spring would always be engaged but would not force the aluminum holding fixture out of the channel. The solution was to increase the length of one of the bolts fastening the holding fixture together and mill a slot into the steel holding fixture where the bolt would ride.

The last component of movement is the yaw axis. This axis is responsible for holding the tooth phantoms as well as being able to rotate around, allowing tests to be conducted at different angles and cycling through different tooth phantoms. The logical choice for this axis of movement was to use a turntable style mounting system. In this design an acrylic turntable sits mounted on an aluminum support which is mounted to the longitudinal sliding platform. A shaft connected to the turntable runs down through the aluminum support to a servo motor directly below. The turntable and related components can be seen in Section B of Figure 2. This design allows for up to four tooth phantoms to be mounted to the turntable; however, a full mandible could be incorporated into the system, satisfying customer need 11 (specifications 2.4 and 3.2).

ELECTRICAL PROGRAMAs per the customer needs, Labview controls the system. The servo/stepper motors of the system, the

ultrasonic pulser/receiver unit, and the oscilloscope can all be easily controlled via Labview. Furthermore, a simple graphic user interface (GUI) can be developed through this program. Once the overall system was understood, a top-level block diagram of the system was created, shown in Figure 5.

Figure 5: Top-level block diagram of system

The Arduino Uno development board was selected to act as the control unit of the fixture. The Arduino Uno microcontroller is known for being a simple development board to utilize, and is easily integrated with Labview,

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which simplifies the programming and manipulation. The servo and stepper motors of the system can all be wired to the Arduino Uno, utilizing shields for the stepper motors. The EasyDriver stepper motor driver was chosen because it is simple and inexpensive and is designed to be integrated with the Arduino development systems.

One main concern with employing stepper motors in the system was the lack of an inherent feedback system. Alternative means had to be considered to ensure that there would be no errors/collisions during operation of the overall system and to meet customer need 5 (specifications 4.1 and 4.2). Two methods were considered for this, tripwire sensors and linear potentiometers (pots). The tripwire sensors work best as a shutoff feature, ensuring no collisions occur during operation. However, the fixture would require complicated adaptation to work properly with the sensors, and there were worries that they would not be reliable or quick enough to work. The pots would function as position systems via voltage dividers and minimal adaptation was expected with the mechanical fixture. Thus it was decided to use the pots for the feedback system. Slide pots were selected instead of linear motion pots as slide pots are cheaper.

The voltage divider circuits were built onto three prototyping boards. The circuit required was elementary enough to require very little space, so the boards were cut in half vertically to simplify the mounting. The circuit uses a 1kΩ resistor. The components were soldered onto the prototyping boards into separate grid spaces with wires soldered to make connection points. A PC board terminal was used for voltage and ground ports of the boards, and 22AWG wire was used to act as the output voltage of the voltage divider which would be connected to the Arduino Uno’s Analog to Digital Converter (ADC) for use as the feedback system.

A 12VDC power supply was used to power the motors. The power supply has a current rating of 4.2A, which is more than sufficient for the current requirements of the five motors. The voltage dividers are driven by the 5VDC power rails of the Arduino Uno, and are able to output roughly between 0VDC and 5VDC in 0.1VDC increments.

The pulser/receiver unit borrowed for this project was a JSR DPR35E. Labview was used to communicate with and control the unit. The unit is only able to respond via hexadecimal commands so a user front panel was created to facilitate easier interaction. At first, there were issues with trying to initialize the unit and test if there was proper communication. The unit was unable to send responses when prompted to do so during initialization. It was believed to be a hardware issues; the problem was resolved through use of a different RS-232 card. This was a potentially large problem since the DPR35E unit has no dials for control on the front panel, which meant everything had to be controlled through Labview. However, a second attempt ensuring proper connections resulted in a successful initialization.

Following the instruction manual, the pulser/receiver unit was connected to the computer and to an oscilloscope. The oscilloscope utilized for the system was a Tektronix TDS 2012C unit. Labview has virtual instrument (VI) support for Tektronix products, allowing for better and easier control and integration with the oscilloscope for data acquisition. Pulse-Echo Mode operation was utilized for testing, so the DPR35E was connected based on the diagram shown in Figure 6. The computer was connected to the Input port of the RS-232 Interface of the unit.

Figure 6: DPR35E pulse-echo mode operation

The unit must be initialized before it can receive function control commands. A program was created in order to test the initialization and command prompts of the unit, 13061-Pulser-TS.VI. Upon testing the communication of the system the DPR35E returned the requested information, showing that the pulser/receiver was able to accept and return information. Initialization mode was exited and the DPR35E was allowed to accept function command prompts.

The Tektronix TDS 2012C oscilloscope was used to capture and display the data obtained from the 10 MHz transducer. With VI support readily available via Labview, a GUI was created that controlled the settings of the oscilloscope and displayed the waveform. The oscilloscope was tested during operation of the pulser/receiver

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unit in order to determine the best settings for display. A Labview GUI was developed with the settings and waveform display contained in one VI.

Proper integration of the DPR35E pulser/receiver, the Tektronix oscilloscope, and the motor control was necessary to meet customer need 6 (specifications 5.1, 5.2, 6.1). A main VI was developed in order to facilitate this, 13061-Start-Menu.vi. This VI acts as the Front Panel through which the system testing is performed and automated. The sampled data is outputted to a dedicated folder for future analysis.

RESULTS AND DISCUSSION As was previously mentioned, the customer needs and the project specifications were both revised. That

being said, the revised specifications were all successfully met. The ability of the motors to move the fixture through all five axes was manually tested using the Labview program developed. Initially, the team struggled with movement in three of the five axes. It was assumed that the fixture simply exhibited too much friction for the motors to overcome. However, after further analysis it became clear that the motor capabilities were far beyond the torque required to move the fixture and the motors were not performing to their specifications. Eventually, the team was able to overcome this barrier and achieve movement in all five axes, proving the success of the mechanical fixture.

The tooth phantom requirements became simplified as well; the team was only responsible for selecting materials that differed enough from one another to allow ultrasonic detection of the material boundary. This was achieved via the use of concrete, aluminum, rubber and fabric paint. Unfortunately, the fabric paint underwent minor degradation due to the use of a coupling agent in the testing process. However, the tooth phantoms successfully met the revised customer needs. To test the detectability of the material boundary the ultrasonic probe was placed against the rubber or fabric paint surface and a pulse was transmitted. Each spike seen on the oscilloscope output represents a material boundary. Therefore, the presence of multiple spikes indicates multiple material layers as is illustrated in Figure 7 below.

After the reduction in customer needs, the electrical portion of the project no longer needed to translate the voltage outputs to a sulcus depth measurement. Therefore, the success of the electrical program was determined based upon its usability and ability to store data. As seen in Figure 8 below, the front panel of the program certainly simplifies the process and leaves little room for error. Furthermore, the test results were positively stored in a specified file, making the electrical portion of the project a success.

Figure 7: Test output Figure 8: Front panel

CONCLUSIONS AND RECOMMENDATIONS Throughout initial work on the project the team quickly discovered that not all customer needs were

attainable. Multiple discussions with the customer and the faculty guide led to a revision of project scope. The

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team was able to move the probe in all five axes and detect the interface between differing materials. Initially, the team was responsible for crafting a tooth phantom whose materials had ultrasonic properties similar to those of relevant human tissue. However, not much data could be found regarding the ultrasonic behavior of human teeth and there simply was not enough time to conduct independent research. Therefore, the team put forth the best effort possible to select materials that would behave similar to human tissue, however the team was not able to confirm or prove similar behavior. The customer needs were reduced to require that the team be able to detect a difference in materials, rather than provide a phantom ultrasonically similar to biological materials. The tooth phantom also succeeded in varying the sulcus depth via the incorporation of multiple teeth.

The mechanical fixture proved to be a great challenge as the team chose to machine nearly the entire fixture in house. This was primarily done in an attempt to conserve the budget. Ultimately, the fixture was finished and functioned as required. However, if the project was to be completed again, the team would likely opt to order pre-fabricated pieces where possible.

The electrical programming of the system was very difficult and time consuming. Initially, the team was responsible for interpreting the output received from the ultrasonic probe. The output received via an oscilloscope was a voltage reading, requiring that the team perform an in depth analysis to combine the voltage reading with known distances traveled to calculate the sulcus depth. However, given the short timeline of the project and the difficulty of that calculation, the customer needs were reduced for the electrical portion of the project as well. The team was ultimately responsible for moving the transducer in five axes, collecting the data and storing it in a file for post-test analysis. The team was able to successfully fulfill the revised customer needs.

Future generations of this project should consider a few things. First and most importantly, any future work to be performed on this project will likely require an ultrasonic transducer with higher capability. After conversations with experts in the field, the team learned that a transducer with a frequency of 10 MHz was not sufficient for detecting the minute differences in the human tissues in and around the sulcus. A contact probe was selected for testing; however there are other types of transducers (i.e. immersion) that might be better suited for this application. Unfortunately, the team was restricted by knowledge, time and budget and was therefore unable to perform greater research regarding ultrasonic transducers. Furthermore, the motors selected for the project (particularly the servo motors) are under great stress when moving the ultrasonic probe. The servo motors could be mounted differently to reduce the associated angular torque or they could be replaced with higher quality motors. A better feedback system will be required for the stepper motors. The ADC on the Arduino is only 8-bits and the potentiometers have inherent noise. Due to these limiting factors, the feedback system is not precise enough to account for any slip in the stepper motors. The stepper motors could also benefit from a larger power supply. The 12 V supply works well, however an 18 V supply would be more efficient in terms of motor output. The wire harnesses should be cleaned up using better connectors than the quick disconnects used for this generation. Lastly, as was previously mentioned, materials for use in the tooth phantom should undergo further research to improve the phantom’s resemblance to human tissue.

ACKNOWLEDGMENTS The team would like to thank the following individuals and organizations for their contributions to the project:

Organizations

Rochester Institute of Technology (RIT) University of Rochester (U of R)

Individuals

Dr. Brown – RIT Dr. Caton – U of R Neal Eckhaus, faculty guide Dr. Helguera – RIT Professor Landschoot – RIT Dr. Stephen McAleavy – (U of R) Dr. Phillipps – RIT Dr. Rosenblum, customer

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APPENDIX A – Customer NeedsCustomer Need Description

CN 1 Ability to vary the sulcus depth with a resolution of 0.1 mmCN 2 Ability to measure the sulcus depth with an accuracy of +/- 0.1 mmCN 3 Ability to quickly alter the geometry of the tooth in the fixtureCN 4 Ability to quickly alter the physical relationship of the tooth with respect to the gumCN 5 Ability to programmatically control the orientation of the ultrasonic probe in 5 axesCN 6 Ability to programmatically start and stop data collection from the ultrasonic probeCN 7 Ability to use ultrasound coupling agents from standard gel to semisolid couplersCN 8 A tooth phantom that is not made from biomaterials that has ultrasonic properties similar to human

teethCN 9 A gum phantom that is not made from biomaterials that has ultrasonic properties similar to human

gum tissueCN 10 A bone phantom that is not made from biomaterials that has ultrasonic properties similar to human

boneCN 11 Ability to replace the phantom with a human or pig mandibleCN 12 Ability to replace the ultrasonic system with an alternate system that can maintain the physical

relationship between the ultrasound tip and the dental components

APPENDIX B – SpecificationsSpecification Description CN

1.0 Test Probe Fixture

1.1 The test probe fixture must be able to move through 3 axes 51.2 The test probe fixture shall be compact and portable 121.3 The test probe fixture shall be simply constructed to allow for maintenance to be

performed by untrained personnel relying solely on an instruction manual (to be provided)

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1.4 The test probe fixture shall allow for position changes on/about any of the 3 axes to a programmatically specified point to within 0.1mm for linear movement or 1° for angular movement

2,5,6

2.0 Phantom Holding Fixture

2.1 The phantom holding fixture must be able to move through 2 axes 52.2 The phantom holding fixture shall be simply constructed to allow for maintenance to be

performed by untrained personnel relying solely on an instruction manual (to be provided)

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2.3 The phantom holding fixture shall allow for position changes on/about any of the 2 axes to a programmatically specified point to within 0.1mm for linear movement or 1° for angular movement

2,5,6

2.4 The phantom holding fixture shall allow for the tooth phantom to be replaced by a biological mandible

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3.0 Tooth Phantom

3.1 The tooth phantom shall be made of non-biological materials that mimic human tissue with respect to ultrasonic wave propagation

8,9,10

3.2 The tooth phantom shall be able to be replaced within the fixture in a reasonable amount of time (< 10 minutes)

3,11

3.3 The tooth phantom geometry shall allow for quick alterations of the physical relationship between the tooth and the gums

1,4

4.0 Motor Control

4.1 The motors must facilitate accurate & repeatable movement of the ultrasonic probe through 5 axes via programmatic controls

2,5,6

4.2 The motors must allow for positions changes on/about any axis to a programmatically specified point to within 0.1mm for linear movement or 1° for angular movement

2,5,6

5.0 Data Acquisition

5.1 The program must be able to remotely acquire and interpret data from the ultrasonic probe via oscilloscope outputs

2,6,12

5.2 The program must be able to accurately & repeatedly acquire data from the ultrasonic probe via oscilloscope outputs

1,2,5,6

6.0 Limit Comparison

6.1 The program developed must be able to log and compare data to a standard 6,12

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