Tactile Imager Research Articles

The impact of short-term pelvic floor muscle training on the biomechanical parameters of the pelvic floor among patients with stress urinary incontinence: A pilot study

ObjectiveOur study aimed to improve the understanding of the biomechanical changes occurring in the pelvic floor due to pelvic floor muscle training (PFMT), which is responsible for improving stress urinary incontinence (SUI) symptoms. Study designIn this prospective cohort study, we examined the impact of a six-week PFMT program in women with stress or stress-predominant urinary incontinence on the biomechanical parameters of the pelvic floor. Fifty-two biomechanical parameters were measured by Vaginal Tactile Imager (VTI) at baseline and at a six-week follow-up. In addition, we have assessed the Urinary Distress Inventory (UDI-6), Incontinence Impact Questionnaire (IIQ-7), and Patient’s Global Impression of Severity (PGI-S) scores at enrolment and at six-week follow-up. We have divided our cohort into two groups, Improved Group (IG) and Not-improved Group (NIG), based on the change in UDI-6 score after six weeks and compared the biomechanical changes within and between the two groups. ResultsThe overall cohort included twenty women with stress or stress-predominant SUI based on MESA questionnaire [MESA SUI index (mean ± SD) 63.3 % ± 24.0 %, MESA UUI index (mean ± SD) 13.3 % ± 15.3 %, p < 0.01]. Nine of the 52 VTI parameters have changed significantly after six weeks of PFMT in the entire cohort. Eleven women (IG) achieved the minimum 11-point change in the UDI-6 scaled score. In IG, we found that three VTI parameters differed significantly: Parameter 1: the maximum value of force measured during the VTI probe insertion [(N, mean ± SD) 0.55 ± 0.18 vs. 0.78 ± 0.31, p < 0.049], parameter 18: the maximum gradient at the upper third of the vagina (posterior) [(kPa/mm, mean ± SD) 0.16 ± 0.05 vs. 0.36 ± 0.28, p < 0.048], and parameter 47: integral force change in the anterior compartment at reflex pelvic muscle contraction (cough) [(N, mean ± SD) 1.61 ± 0.85 vs. 1.97 ± 0.71, p < 0.045]. ConclusionOur study revealed a significant association between the improvement of strength in targeted muscle groups and a reduction in urinary incontinence symptoms. Identifying specific muscles changing PFMT provides valuable insights for specific interventions. Our findings may help to create personalized and targeted interventions to improve the quality of life of women affected by SUI.

Biomechanical Integrity Score of the Female Pelvic Floor for Stress Urinary Incontinence

Introduction and hypothesisThis study is aimed at developing and validating a new integral parameter, the Biomechanical Integrity score (BI-score) of the female pelvic floor for stress urinary incontinence conditions.MethodsA total of 130 subjects were included in the observational cohort study; 70 subjects had normal pelvic floor conditions, and 60 subjects had stress urinary incontinence (SUI). A Vaginal Tactile Imager (VTI) was used to acquire and automatically calculate 52 biomechanical parameters for eight VTI test procedures (probe insertion, elevation, rotation, Valsalva maneuver, voluntary muscle contractions in two planes, relaxation, and reflex contraction). Statistical methods were applied (t test, correlation) to identify the VTI parameters sensitive to the pelvic SUI conditions.ResultsTwenty-seven parameters were identified as statistically sensitive to SUI development. They were subdivided into five groups to characterize tissue elasticity (group 1), pelvic support (group 2), pelvic muscle contraction (group 3), involuntary muscle relaxation (group 4), and pelvic muscle mobility (group 5). Every parameter was transformed to its standard deviation units using the dataset for normal pelvic conditions, similar to the T-score for bone density. Linear combinations with specified weights led to the composition of five component parameters for groups 1–5 and to the BI-score in standard deviation units. The p value for the BI-score has p = 4.0 × 10–28 for SUI versus normal conditions.ConclusionsQuantitative transformations of the pelvic tissues, support structures, and functions under diseased conditions may be studied with the SUI BI-score in future research and clinical applications.

A randomized controlled pilot trial to assess the effectiveness of a specially formulated food supplement and pelvic floor muscle training in women with stress-predominant urinary incontinence

BackgroundPelvic floor muscle training (PFMT) is the first-line treatment approach for stress urinary incontinence. Creatine and leucine have been shown to improve muscle function. Our aim was to assess the effectiveness of a food supplement and PFMT in women with stress-predominant urinary incontinence.MethodsWomen with stress-predominant urinary incontinence were randomized in 1:1 ratio to receive daily oral supplementation for six weeks with either a food supplement (treatment group) or placebo (control group). Both groups were instructed to perform standardized daily PFMT. The primary outcome was the Urogenital Distress Inventory Short Form (UDI-6) score. Secondary outcomes were the Incontinence Impact Questionnaire (IIQ-7) score, Patient’s Global Impression of Severity (PGI‐S), and Biomechanical Integrity score (BI-score) measured by Vaginal Tactile Imager. To have a power of 80% and a significance level of 5% to detect a decrease of 16 points in the UDI-6 score, a sample size of 32 was needed, with 16 patients in each arm of our trial.ResultsSixteen women in the control group and sixteen in the treatment group completed the trial. Between-group analysis revealed no significant differences between the control and treatment group except for mean change (delta) in vaginal squeeze pressure [(cmH2O, mean ± SD), 5 ± 12 vs. 15 ± 15, P = 0.04] and mean change (delta) in PGI-S score [(mean ± SD), -0.2 ± 0.9 vs. -0.8 ± 0.8, P = 0.04]. Within-group analysis showed that UDI-6 and IIQ-7 scores improved significantly from baseline to six weeks in the treatment group but not in the control group [UDI-6 score (mean ± SD) 45 ± 21 vs. 29 ± 21, P = 0.02; 43 ± 18 vs. 33 ± 26, P = 0.22] [IIQ-7 score (mean ± SD) 50 ± 30 vs. 30 ± 21, P = 0.01; 48 ± 23 vs.40 ± 28, P = 0.36]. PGI-S scores only improved in the treatment group from baseline to six weeks after treatment [PGI-S score (mean ± SD) 3.1 ± 0.8 vs. 2.3 ± 0.8, P = 0.0001]. BI-score, on average, improved significantly in the treatment and control group as well [SD unit, mean, from − 1.06 to -0.58, P = 0.001; from − 0.66 to -0.42, P = 0.04].ConclusionsWomen with stress-predominant urinary incontinence receiving a specially formulated supplement in addition to daily PFMT for six weeks had significantly improved urinary symptoms (decrease in UDI-6 score and IIQ-7) and BI-score compared to their baseline.Trial registrationClinicalTrials.gov Identifier: NCT05358769. 27/04/2022.

A Randomized Controlled Trial to Assess the Effectiveness of a Specially Formulated Food Supplement and Pelvic Floor Muscle Training in Women With Stress-Predominant Urinary Incontinence [ID: 1372768

INTRODUCTION: The objective of this study was to assess the effectiveness of a creatine-leucine-based food supplement and standardized pelvic floor muscle training (PFMT) in women with stress-predominant urinary incontinence (SUI). METHODS: Women with SUI were randomized to receive daily oral supplementation for 6 weeks with either a supplement or placebo. Both groups were instructed to perform daily PFMT at an intensity of at least 75% of one repetition maximum of 45 pelvic floor muscle contractions per day. The primary outcome was the Urogenital Distress Inventory Short Form (UDI-6) score. Secondary outcomes were the Incontinence Impact Questionnaire (IIQ-7) score, Biomechanical Integrity (BI) score measured by Vaginal Tactile Imager. To have a power of 80% and a significance level of 5%, a sample size of 32 was needed. The trial was IRB approved. RESULTS: Within-group analysis showed that UDI-6 and IIQ-7 scores improved significantly from baseline to 6 weeks in the treatment group but not in the control group (UDI-6 score [mean±SD], 45±21 versus 29±21, P=.02; 43±18 versus 33±26, P=.22) (IIQ-7 score [mean±SD], 50±30 versus 30±21, P=.01; 48±23 versus 40±28, P=.36). Out of the 52 examined VTI parameters, significantly more parameters improved in the treatment group compared to the control group (11/52 versus 3/52, P=.04). BI-score, on average, improved significantly in the treatment and control group as well (SD unit, mean, from −1.06 to −0.58, P=.001; from −0.66 to −0.42, P=.04). CONCLUSION: Women with SUI receiving a specially formulated supplement in addition to daily PFMT for 6 weeks had improved urinary symptoms (significant decrease in UDI-6 and IIQ-7 scores) and better BI score compared to baseline.

Biomechanical integrity score of the female pelvic floor

Introduction and HypothesisThe aim of this study is to develop and validate a new integral parameter, the Biomechanical Integrity score (BI-score), for the characterization of the female pelvic floor.MethodsA total of 253 subjects with normal and pelvic organ prolapse (POP) conditions were included in the multi-site observational, case-control study; 125 subjects had normal pelvic floor conditions, and 128 subjects had POP stage II or higher. A Vaginal Tactile Imager (VTI) was used to acquire and automatically calculate 52 biomechanical parameters for eight VTI test procedures (probe insertion, elevation, rotation, Valsalva maneuver, voluntary muscle contractions in two planes, relaxation, and reflex contraction). Statistical methods were applied (t-test, correlation) to identify the VTI parameters sensitive to the pelvic conditions.ResultsTwenty-six parameters were identified as statistically sensitive to POP development. They were subdivided into five groups to characterize (1) tissue elasticity, (2) pelvic support, (3) pelvic muscle contraction, (4) involuntary muscle relaxation, and (5) pelvic muscle mobility. Every parameter was transformed to its standard deviation units against the patient age similar to T-score for bone density. Linear combinations with specified weights led to the composition of five component parameters for groups (1)–(5) and the BI-score in standard deviation units. The p-value for the BI-score has p = 4.3 × 10−31 for POP versus normal conditions. A reference BI-score curve against age for normal pelvic floor conditions was defined.ConclusionsQuantitative transformations of the pelvic tissues, support structures, and functions under diseased conditions may be studied with the BI-score in future research and practical applications.

Tactile Guidance System for the Blind Based on Digital Image Processing

Science and technology are making earth-shaking changes in our daily lives, and as a special group, blind people should enjoy the fruits of technological progress. Since the traditional blind guiding device can only give rough information about the distance and orientation of the obstacle, the user obtains too little information, and there is still too much unknown fear during the traveling. The guiding effect is not great. Therefore, after considering the physical and psychological needs of the blind, this paper designs a system of tactile perception imaging instead of vision. The system collects obstacle information through the camera, performs digital image processing, and then displays it on the tactile imager through special encoding processing. Through the sense of touch, the blind person processes the tactile information into image information through the brain, thereby obtaining the size, shape and position information of the obstacle, and then forming a more concrete understanding of the obstacle, so that the blind can perfectly avoid the obstacle.

Characterization of Perineum Elasticity and Pubic Bone-Perineal Critical Distance with a Novel Tactile Probe: Results of an Intraobserver Reproducibility Study.

Background:Tactile imaging provides biomechanical mapping of soft tissues. Objective biomechanical and anatomical assessment of critical structures within the vagina and pelvis may allow development and validation of a clinical tool that could assist with clinical decisions regarding obstetrical procedures and mode of delivery. Objective: To assess intraobserver reproducibility of measurements of perineal elasticity and pubic bone-perineal critical distance with a novel tactile probe in pregnant women.Methods:An Antepartum Tactile Imager (ATI) was designed with a vaginal probe resembling a fetal skull. The probe comprises 128 tactile sensors on a double curved surface and measures 46 mm in width and 72 mm in length. The probe has a motion tracking sensor that allows acquisition of 3D tactile images. There were two arms of the study. In the first arm, biomechanical mapping of the perineum and pelvic bone location was performed in 10 non-pregnant women for purposes of demonstrating safety and feasibility. In the second arm, biomechanical mapping was performed in 10 pregnant women to explore intraobserver reproducibility. Each subject had two standardized examinations over 3 – 5 minutes by the same observer. Examination comfort and pain levels were assessed by post-procedure survey. Reproducibility was analyzed by intraclass correlation coefficients (ICC) with 95% confidence intervals and Bland-Altman plots. Bias and the 95% limits of agreement were also calculated.Results:The safety and feasibility arm of the study demonstrated high degree of safety and tolerability and reliable acquisition of tactile signals. In the reproducibility arm, 10 pregnant women were recruited at mean gestational age of 34.2 ± 6.5 weeks. The mean perineum elasticity (Young’s modulus, E) was 9.8 ± 5.9 kPa, and the mean pubic bone-perineal critical distance (D) at 20 kPa load was 34.6 ± 6.2 mm. The ICC was 0.97 [95% confidence interval (CI) 0.91, 0.99] and 0.82 [CI 0.44, 0.95] for E and D respectively, consistent with excellent intrarater agreement. The bias and the 95% limits of agreement of E were −6.3% and −29.4% to +16.7%, respectively. The bias and the 95% limits of agreement of D were −2.6% and −25.3% to +20.2%, respectively.Conclusions:The tactile imaging data obtained in the study reproducibly characterized perineal elasticity and pubic bone-perineal critical distance. Further evaluation of this tool in clinical settings is warranted.

91: Biomechanical mapping of pelvic floor restoration after prolapse surgery

The objective of this study is to explore biomechanical transformations of the female pelvic floor after pelvic organ prolapse (POP) surgeries. The prospective multi-center Phase III clinical trial (NCT02925585) was designed to explore changes in tissue elasticity, pelvic support structure strengths and pelvic muscle functions after POP surgeries. To date, 105 subjects were enrolled at five clinical sites, each with planned surgical procedures as the best fit proposed for the specific pelvic conditions by an urogynecologist and accepted by the patient. The applied surgical procedure set includes: supracervical hysterectomy, total hysterectomy, sacrocolpopexy, uterosacral ligament suspension, anterior and posterior colporrhaphy with and without graft augmentation, enterocele repair and perineorrhaphy. A Vaginal Tactile Imager (VTI) was used to acquire comprehensive data for biomechanical mapping of the pelvic floor. The VTI measurements were completed at rest with manually applied deflection pressures to vaginal walls and with pelvic muscle contractions. An analytical software package allowed automated computation of 52 biomechanical parameters for 8 VTI test procedures: (1) probe insertion, (2) elevation, (3) rotation, (4) Valsalva maneuver, (5-6) voluntary muscle contractions in 2 planes, (7) relaxation, and (8) reflex contraction at cough. Patient pelvic pre- and post-operative (4+ months) conditions and VTI data were analyzed to identify statistically significant changes in the biomechanical parameters by paired t-test. Interim analysis of 137 completed to date POP surgical procedures on 54 subjects demonstrates that 25 of 52 biomechanical parameters have statistically significant changes (p<0.05) with identified surgical procedures. A wide range of patient demographics across geographic regions and uses of a range of surgical approaches was observed. The proposed biomechanical mapping data are being integrated into a mathematical model to predict outcome of a surgical treatment based on the patient-specific pelvis clinical history/conditions and VTI preoperative examination results. This study represents the largest set of pelvic biomechanical data collected prospectively before and after POP surgery to date. The observed changes in parameters collected before and after the POP surgery suggest that the proposed biomechanical mapping could be effectively used to complement other diagnostic approaches and aid in choice of indication and assessment of the intervention across varied clinical conditions and procedures.

Biomechanical Mapping of the Female Pelvic Floor: Prolapse versus Normal Conditions.

Background:Quantitative biomechanical characterization of pelvic supportive structures and functions in vivo is thought to provide insight into pathophysiology of pelvic organ prolapse (POP). An innovative approach—vaginal tactile imaging—allows biomechanical mapping of the female pelvic floor to quantify tissue elasticity, pelvic support, and pelvic muscle functions. The Vaginal Tactile Imager (VTI) records high definition pressure patterns from vaginal walls under an applied tissue deformation and during pelvic floor muscle contractions.Objective:To explore an extended set of 52 biomechanical parameters for differentiation and characterization of POP relative to normal pelvic floor conditions.Methods:96 subjects with normal and POP conditions were included in the data analysis from multi-site observational, case-controlled studies; 42 subjects had normal pelvic floor conditions and 54 subjects had POP. The VTI, model 2S, was used with an analytical software package to calculate automatically 52 biomechanical parameters for 8 VTI test procedures (probe insertion, elevation, rotation, Valsalva maneuver, voluntary muscle contractions in 2 planes, relaxation, and reflex contraction). The groups were equalized for subject age and parity.Results:The ranges, mean values, and standard deviations for all 52 VTI parameters were established. 33 of 52 parameters were identified as statistically sensitive (p < 0.05; t-test) to the POP development. Among these 33 parameters, 11 parameters show changes (decrease) in tissue elasticity, 8 parameters show deteriorations in pelvic support and 14 parameters show weakness in muscle functions for POP versus normal conditions.Conclusions:The biomechanical mapping of the female pelvic floor with the VTI provides a unique set of parameters characterizing POP versus normal conditions. These objectively measurable biomechanical transformations of pelvic tissues, support structures, and functions under POP may be used in future research and practical applications.

Tactile Imaging Markers to Characterize Female Pelvic Floor Conditions.

The Vaginal Tactile Imager (VTI) records pressure patterns from vaginal walls under an applied tissue deformation and during pelvic floor muscle contractions. The objective of this study is to validate tactile imaging and muscle contraction parameters (markers) sensitive to the female pelvic floor conditions. Twenty-two women with normal and prolapse conditions were examined by a vaginal tactile imaging probe. We identified 9 parameters which were sensitive to prolapse conditions (p < 0.05 for one-way ANOVA and/or p < 0.05 for t-test with correlation factor r from −0.73 to −0.56). The list of parameters includes pressure, pressure gradient and dynamic pressure response during muscle contraction at identified locations. These parameters may be used for biomechanical characterization of female pelvic floor conditions to support an effective management of pelvic floor prolapse.

A three-axis high-resolution capacitive tactile imager system based on floating comb electrodes

We present the design, fabrication and testing of a high-resolution 169-sensing cell capacitive flexible tactile imager (FTI) for normal and shear stress measurement as an auxiliary sensor for robotic grippers and gait analysis. The FTI consists of a flexible high-density array of normal stress and two-dimensional shear stress sensors fabricated using microelectromechanical systems (MEMS) and flexible printed circuit board (FPCB) techniques. The drive/sense lines of the FTI are realized using FPCB whereas the floating electrodes (Au) are patterned on a compressible PDMS layer spin coated on the FPCB layer. The use of unconnected floating electrodes significantly improves the reliability of traditional quad-electrode contact sensing devices by eliminating the need for patterning electrical wiring on PDMS. When placed at the heel of a boot, this FTI senses the position and motion of the line of contact with the ground. Normal stress readouts are obtained from the net capacitance of the cell and the shear-sense direction is determined by the amount of asymmetric overlap of the floating combs with respect to the bottom electrodes. The FTI is characterized using a high-speed switched-capacitor circuit with a 12-bit resolution at full frame rates of 100 Hz (∼0.8 Mb s−1) capable of resolving a displacement as low as 60 µm. The FTI and the readout circuitry contribute to a noise/interference level of 5 mV and the sensitivity of normal and shear stress for the FTI is 0.38 MPa−1 and 79.5 GPa−1 respectively.

Vaginal tactile imaging.

Changes in the elasticity of the vaginal walls, connective support tissues, and muscles are thought to be significant factors in the development of pelvic organ prolapse, a highly prevalent condition affecting at least 50% of women in the United States during their lifetimes. It creates two predominant concerns specific to the biomechanical properties of pelvic support tissues: how does tissue elasticity affect the development of pelvic organ prolapse and how can functional elasticity be maintained through reconstructive surgery. We designed a prototype of vaginal tactile imager (VTI) for visualization and assessment of elastic properties of pelvic floor tissues. In this paper, we analyze applicability of tactile imaging for evaluation of reconstructive surgery results and characterization of normal and pelvic organ prolapse conditions. A pilot clinical study with 13 patients demonstrated that VTI allows imaging of vaginal walls with increased rigidity due to implanted mesh grafts following reconstructive pelvic surgery and VTI has the potential for prolapse characterization and detection.

A multifunctional integrated silicon tactile imager with arrays of strain and temperature sensors on single crystal silicon diaphragm

In this study, a silicon multifunctional tactile imager with the simultaneous detection abilities of ‘3D surface shape’ and ‘temperature distribution’ of touching object has been realized with silicon LSI/MEMS technology. The pixel circuit array including a piezoresistor and a temperature sensor is integrated on elastic surface of pneumatically swollen silicon diaphragm. Also, elasticity detection of touching object has been simultaneously realized with signal processing in frequency domain. Prototype tactile imagers with a 3.1 mm × 3.1 mm sensor diaphragm integrating 420-μm pitch multifunctional sensor pixel array have been fabricated. In the evaluation experiments, the shape of a 1.5 mmϕ soft tube was successfully detected. Also, simultaneous measurement of surface shape and temperature distribution was performed using a heated metal pipe. The detectable lower-limit of vibration in this tactile imager was below 1.0 μm with signal bandwidth more than 2 kHz. Using the ability of vibration detection, the three kinds of materials with different elasticity (0.59–7.04 mN/μm) were successfully distinguished with the tactile imager. The highly sensitive and multifunctional tactile imager with versatile detection ability has been realized by sophisticated integration ability of silicon-MEMS technology.

Tactile breast imaging to increase the sensitivity of breast examination

1037 Background: Most breast cancers in the US are detected by palpation. We evaluated a Tactile Breast Imager (TBI) in the detection of breast nodules in phantoms. The TBI is a hand-held electronic palpation device developed at Artann Laboratories that translates tissue elastic properties into a digital 3-D map of the tissue. Methods: Ten breast phantoms in various sizes containing a total of 36 solid nodules were constructed out of a specially designed silicon compound with elasticity moduli typical for breast tissues. The nodules varied in size from 6 to 30 mm. The depth of placement varied from 10 to 50 mm. Eight of the phantoms contained 4 to 5 nodules. Two phantoms contained no nodules. The breast phantoms were manually examined for nodules. Then the examiner repeated the examination with the device after about 30 minutes training with the TBI. Examiners included skilled medical professionals (3 surgical oncologist, 3 advanced practice nurses) and unskilled lay persons (3 secretaries and 4 engineers). The four engineers were additionally trained in four additional sessions and repeated the phantom exams. The ability to detect the nodules with and without the TBI by skilled and unskilled examiners was compared. The effect of repeat training was also evaluated. Results: Results of the study are summarized in the table: Conclusion: The use of the tactile breast imager increases the sensitivity of breast palpation when used by lay persons in breast models. The sensitivity increases to the level exceeding that of a trained medical professional, particularly with training. The TBI has the potential to increase the detection of palpable breast models if the phantom findings can be duplicated in vivo. Author Disclosure Employment or Leadership Consultant or Advisory Stock Ownership Honoraria Research Funding Expert Testimony Other Remuneration Artann Laboratories Artann Laboratories Artann Laboratories

Tactile imaging

Many physical principles have been explored for the realization of tactile sensors: resistive, inductive, capacitive, optoelectric, magnetic, piezoelectric and electroacoustic principles, in a variety of configurations. A key problem in the design of a tactile imager is the taxel density, determining the spatial resolution of the device. This paper reviews the various strategies and principles, discusses some particular design problems and gives the state of the art in tactile sensing.

High-density tactile sensor arrays

In this paper, several different approaches for high-density tactile sensor arrays are first briefly examined. Among them, a silicon micromachined tactile imager approach is very attractive through achieving high density and good reproducibility, and can be mass produced. Therefore, silicon tactile imagers, including the results of very recent research efforts, are described in detail in this paper.

A Flexible High Resolution Tactile Imager with Video Signal Output.

A high resolution and sheetlike form imaging tactile sensor with video signal output has been developed. The sensor has a 64×64 array of sensing elements on a flexible PC board with 1mm spatial resolution. Since the sensor outputs pressure distribution as a video signal, real time tactile image can be observed by using TV monitor. Moreover the same hardware and software of a vision system can be used for measured data handlings, tactile image processing and recording are very simple. As the sensor is made up of a sheet of pressure conductive rubber and stripe electrodes, there are undesiable current passes between sensing elements. Thus these undesiable current passes must be cut within a short scanning priod (500 ns for each element). We used a ground potential method and proved it useful under such a high speed scanning condition. The properties of pressure conductive rubber, including hysteresis and creap effects, are presented. A spatial filtering effect of an elastic cover for a tactile sensor is also analyzed. And it is proved this effect is very important. The final section shows measured data and image processing examples.

Sensors by micromachining

AbstractPhotofabrication developed for integrated circuits can be used to fabricate sensors with three‐dimensional structures and devices with many other types of structures. The micromachining technology is useful in forming a small‐sized, high‐performance sensor system. Using this technology, it is possible to form a system with a sensor, actuator, and electronic circuit on a silicon wafer.A thermo‐flow sensor was fabricated with two microheaters to detect small gas flow. It was found that this device was sensitive to detect an extremely low gas flow with high linearity. This flow sensor was used for an integrated mass‐flow controller and as an integrated magnetic oxygen sensor.An integrated capacitive pressure sensor also was developed with a capacitive detection circuit. The new feed‐through structure used for this sensor was used for other integrated sensors such as a tactile imager.

Fabrication of semiconductor tactile imager

AbstractTo realize a robot with a high degree of functions, pressure sensors are essential. In particular, a tactile imager with a high density of pressure sensors must be developed. To efficiently withdraw information from numerous sensors and to minimize wirings from the sensors, it is necessary to install a switching circuit on each sensor. For these reasons, a semiconductor sensor is the most suitable.In this study, we fabricated a semiconductor tactile imager with 64 silicon piezoelectric pressure sensors on a flexible substrate. Although all 64 sensors did not function, the basic characteristics and efficiency of the device were evaluated.The dimensions of each sensor were 2 mm × 2 mm. The sensor contained a switching circuit with diodes and was assembled on a flexible printed wiring board. Therefore, this device could be mounted on a curved surface and have a strong resistance to external force. Because the area of the pressure‐sensitive resistors was air‐tight, the device was resistant to water. This device also could be produced by batch process and did not require any additional fabrication process.

A 1024-element high-performance silicon tactile imager

A 32*32-element capacitive silicon tactile imager, for use in precision robotics applications where high density and high resolution are important, is discussed. The silicon chip measures 1.6 cm*1.6 cm, and is organized in an X-Y matrix of 1024 capacitor elements on 0.5-mm centers. The process uses two boron diffusions (deep and shallow) followed by a silicon-to-glass electrostatic bonding step and subsequent unmasked wafer dissolution. This results in a thick center plate for the sense capacitor supported by thinner beams. Only four noncritical masking steps for silicon and two for glass are required. A measured force sensitivity of 0.27 pF/gmf/element, temperature sensitivity of less than 3o p.p.m./ degrees C, and maximum operating force of approximately=1 gm/element has been obtained. A discrete data acquisition system used with the device offers over 6 b of force resolution, and the imager can be read at a rate of 15-20 mu s/element, offering an effective frame rate of 5.1 ms. >