An intelligent, multi-transducer signal conditioning design for manufacturing applications

This paper describes a flexible, intelligent, high bandwidth, signal conditioning reference design and implementation, which is suitable for a wide range of force and displacement transducers in manufacturing applications. The flexibility inherent in the design has allowed more than 10 specialised transducer conditioning boards to be replaced by this single design, in a range of bespoke mechanical test equipment manufactured by the authors. The board is able to automatically reconfigure itself for a wide range of transducers and calibrate and balance the transducer. The range of transducers includes LVDT, AC/DC strain gauge and inductive bridges, and a range of standard industrial voltage current interface transducers. Further, with a minor lowcost addition to the transducer connector, the board is able to recognise the type of transducer, reconfigure itself and store the calibration data within the transducer, thereafter allowing a plugand-play operation as transducers are changed. The paper provides an example of the operation in typical manufacturing test application and illustrates the stability and noise performance of the design

A Field Programmable Sequencer and Memory with Middle Grained Programmability Optimized for MCU Peripherals

A Field Programmable Sequencer and Memory (FPSM), which is a programmable unit exclusively optimized for peripherals on a micro controller unit, is proposed. The FPSM functions as not only the peripherals but also the standard built-in memory. The FPSM provides easier programmability with a smaller area overhead, especially when compared with the FPGA. The FPSM is implemented on the FPGA and the programmability and performance for basic peripherals such as the 8 bit counter and 8 bit accuracy Pulse Width Modulation are emulated on the FPGA. Furthermore, the FPSM core with a 4K bit SRAM is fabricated in 0.18µm 5 metal CMOS process technology. The FPSM is an half the area of FPGA, its power consumption is less than one-fifth.Embargo Period 6 month

복강경 수술 로봇 시스템의 활용도 향상을 위한 추가적인 마스터 인터페이스 개발과 이를 이용한 응용 시스템 개발 연구

학위논문 (박사)-- 서울대학교 대학원 공과대학 협동과정 바이오엔지니어링전공, 2017. 8. Sungwan Kim.Robot-assisted laparoscopic surgery offers several advantages compared to open surgery and conventional minimally invasive surgery. However, important issues which need to be resolved are the complexity of current operation room environment for laparoscopic robotic surgery and demand for a larger operation room. To overcome these issues, additional interfaces based on Hands-On-Throttle-And-Stick (HOTAS) concept which can be simply attached and integrated with master interface of da Vinci surgical robot system were proposed. HOTAS controller is widely used for flight control in the aerospace field which can manipulate hundreds of functions and provide feedback to the pilot on flight conditions. The implementation of HOTAS controller significantly reduced the complexity of flights and reduced the number of pilots required in a cockpit from two to one. In this study, to provide above benefits to the operation room for robotic laparoscopic surgery, two types of additional interfaces are proposed. Proposed additional interfaces can be easily manipulated by the surgeons index finger, which is currently operated only by finger clutch buttons, and therefore enable the surgeon to use multiple functions. Initially, a novel master interface (NMI) was developed. The NMI mainly consists of a 9-way switch and a microprocessor with a wireless communication module. Thus, the NMI can be also regarded as a 9-way compact HOTAS. The performance test, latency, and power consumption of the developed NMI were verified by repeated experiments. Then, an improved novel master interface (iNMI) was developed to provide more intuitive and convenient manipulation. The iNMI was developed based on a capacitive touch sensor array and a wireless microprocessor to intuitively reflect the surgeons decision. Multiple experiments were performed to evaluate the iNMI performance in terms of performance test, latency, and power consumption. In addition, two application systems based on Surgical-Operation-By-Wire (SOBW) concept are proposed in this research to enhance the function of laparoscopic surgical robot system based on clinical needs that are stated below. The size of the additional interface is small enough to be easily installed to the master tool manipulators (MTMs) of da Vinci research kit (dVRK), which was used as an operation robot arm system, to maximize convenience to the surgeon when using the additional interfaces to simultaneously manipulate the application systems with the MTMs. Firstly, a robotic assistant that can be simultaneously manipulated via a wireless controller is proposed to allow the surgeon to control the assistant instrument. This approach not only decreases surgeon fatigue by eliminating communication process with assistants, but also resolves collision between the operation robot arms and the assistant instruments that can be caused by an inexperienced assistant or miscommunication and misaligned intent between the surgeon and the assistant. The system comprises two additional interfaces, a surgical instrument with a gripper actuated by a micromotor and a 6-axis robot arm. The gripping force of the surgical instrument was comparable to that of conventional systems and was consistent even after 1,000 times of gripping motion. The workspace was calculated to be 8,397.4 cm3. Recruited volunteers were able to execute the simple peg task within the cut-off time and successfully performed the in vitro test. Secondly, a wirelessly controllable stereo endoscope system which enables simultaneous control with the operating robot arm system is proposed. This is able to remove any discontinuous surgical flow that occurs when the control is swapped between the endoscope system and the operating robot arm system, and therefore prevent problems such as increased operation time, collision among surgical instruments, and injury to patients. The proposed system consists of two additional interfaces, a four-degrees of freedom (4-DOFs) endoscope control system (ECS) and a simple three-dimensional (3D) endoscope. The 4-DOFs ECS consists of four servo motors and employs a two-parallel link structure to provide translational and fulcrum point motions to the simple 3D endoscope. The workspace was calculated to be 20,378.3 cm3, which exceeds the reference workspace. The novice volunteers were able to successfully execute the modified peg transfer task. Throughout the various verifications, it has been confirmed that the proposed interfaces could make the surgical robot system more efficiently by overcoming its several limitations.1. Introduction 1 1.1. Robotic Laparoscopic Surgery 1 1.2. Objectives and Scope 8 1.2.1. Additional Master Interfaces 14 1.2.2. Application Systems 15 2. Materials and Methods 20 2.1. Additional Master Interfaces 20 2.1.1. Novel Master Interface: 9-way Compact Hands-On-Throttle-And-Stick 20 2.1.2. improved Novel Master Interface: Capacitive Touch Type Compact Hands-On-Throttle-And-Stick 26 2.2. Application Systems 34 2.2.1. Robotic Assistant 34 2.2.2. Stereo Endoscope System 49 3. Results 57 3.1. Novel Master Interface with Application Systems 57 3.1.1. Novel Master Interface 57 3.1.2. Robotic Assistant 59 3.1.3. Novel Master Interface with Robotic Assistant 67 3.1.4. Stereo Endoscope System 76 3.1.5. Novel Master Interface with Stereo Endoscope System 82 3.2. improved Novel Master Interface with Application Systems 87 3.2.1. improved Novel Master Interface 87 3.2.2. improved Novel Master Interface with Stereo Endoscope System 90 4. Discussion 91 5. Conclusion 102 References 105 Abstract in Korean 117Docto

Σχεδιασμός και υλοποίηση αναδιαμορφούμενου ενσωματωμένου συστήματος μέτρησης αιθητήρων χωρητικότητας σε FPGA

Οι έξυπνοι αισθητήρες χρησιμοποιούνται όλο και πιο πολύ στις μέρες μας για την παρακολούθηση του περιβάλλοντος. Ουσιαστικά ένας έξυπνος αισθητήρας είναι ένα σύστημα το οποίο περιλαμβάνει εκτός από τα αισθητήρια και έναν επεξεργαστή ο οποίος παρέχει τη δυνατότητα τοπικής επεξεργασίας των μετρήσεων. Στο πλαίσιο της διπλωματικής εργασίας υλοποιήθηκε ένα έξυπνο και ευέλικτο ενσωματωμένο σύστημα για την μέτρηση αισθητήρων χωρητικότητας. Στο σύστημα εκτός από το κύκλωμα διεπαφής των αισθητήρων έχει ενσωματωθεί ένας επεξεργαστής LEON3 με τα απαραίτητα περιφερειακά και έχει εγκατασταθεί λειτουργικό σύστημα Linux. Η υλοποίηση έγινε σε FPGA της σειράς CYCLON της ALTERA στο αναπτυξιακό σύστημα της Terasic DE2-115. Για την μέτρηση των αισθητήρων έχει υλοποιηθεί ένα κύκλωμα διεπαφής το οποίο μετατρέπει της μεταβολές της χωρητικότητας σε μεταβολές συχνότητας με χρήση ενός ειδικά διαμορφωμένου ταλαντωτή δακτυλίου. Ακολούθως, χρησιμοποιείται ένας προγραμματιζόμενος μετρητής συχνότητας ο οποίος διαθέτει μεταβλητό χρονικό παράθυρο μέτρησης ώστε να παρέχει ευελιξία ως προς το χρόνο μέτρησης, την ακρίβεια και το εύρος των μετρούμενων συχνοτήτων. Το κύκλωμα διεπαφής έχει συνδεθεί στον εσωτερικό δίαυλο δεδομένων (AMBA bus) του επεξεργαστή LEON3 ώστε να συμπεριφέρεται ως ένα τυπικό περιφερειακό του επεξεργαστή και να επιτυγχάνεται εύκολη και αποδοτική διαχείρισή του από το λογισμικό της εφαρμογής. Στο δίαυλο AMBA έχουν συνδεθεί και άλλα περιφερειακά όπως για παράδειγμα μια SVGA οθόνη επαφής (touch screen), μια μονάδα δικτύου (ETHERNET) και ένα πληκτρολόγιο τα οποία προσδίδουν στο συνολικό σύστημα επιπλέον δυνατότητες και ευελιξία. Με το ενσωματωμένο λειτουργικό σύστημα Linux ο χρήστης του συστήματος μπορεί να χρησιμοποιεί ένα καθιερωμένο περιβάλλον για την επεξεργασία των μετρήσεων και την επικοινωνία με τους αισθητήρες. Ο χρήστης μπορεί να παρατηρεί τα αποτελέσματα στην SVGA οθόνη ή να εισάγει εντολές επεξεργασίας από το πληκτρολόγιο. Ταυτόχρονα υπάρχει η δυνατότητα απομακρυσμένης σύνδεσης με το σύστημα και μεταφοράς των αποτελεσμάτων σε ένα απομακρυσμένο υπολογιστή. Έχουν υλοποιηθεί προγράμματα σε γλώσσα C για την επεξεργασία των μετρήσεων και για τον έλεγχο του κυκλώματος διεπαφής. Ένα πρόγραμμα το οποίο υλοποιήθηκε αξιοποιεί την “touch screen” λειτουργία της οθόνης, ώστε να μην χρειάζεται απαραίτητα συνδεδεμένο πληκτρολόγιο στο σύστημα. Με το πρόγραμμα αυτό μπορεί να γίνει βαθμονόμηση του αισθητήρα και να υπολογίζεται η μέση τιμή και η διασπορά των μετρήσεων. Για να επαληθευθεί η ορθή λειτουργία του συστήματος ελήφθησαν μετρήσεις με χωρητικούς αισθητήρες αερίων οι οποίοι αποτελούνται από διαπλεκόμενα (interdigitated) ηλεκτρόδια και ένα στρώμα πολυμερούς, του οποίου οι ιδιότητες μεταβάλλονται με την απορρόφηση συγκεκριμένων αερίων. Η απόκριση του προτεινόμενου συστήματος για διάφορες συγκεντρώσεις αναλυτών συγκρίθηκε με τις μετρήσεις των ίδιων αισθητήρων με σύστημα γέφυρας και προέκυψε ικανοποιητική σύμπτωση. Η ευαισθησία του συστήματος είναι, επίσης, ικανοποιητική γιατί δίνει τη δυνατότητα μέτρησης πολύ μικρών μεταβολών της χωρητικότητας οι οποίες αντιστοιχούν σε μεταβολή μερικών δεκάδων Hz στη συχνότητα ταλάντωσης. Το σύστημα που υλοποιήθηκε μπορεί να χρησιμοποιηθεί σε πλήθος εφαρμογών και να προσαρμοστεί σε διαφορετικά περιβάλλοντα. Με την ενσωμάτωση του επεξεργαστή LEON3 ο οποίος είναι ευέλικτος και παραμετροποιήσιμος μπορούν να γίνουν εύκολα προσθήκες υλικού (hardware) και να προσαρμοστεί κατάλληλα το λογισμικό ώστε να προστεθούν επιπλέον λειτουργίες. Συνολικά, στην διπλωματική εργασία παρουσιάζεται ένα ευέλικτο, αυτόνομο, εύχρηστο και αποδοτικό “έξυπνο” σύστημα για την μέτρηση αισθητήρων χωρητικότητας, το οποίο περιλαμβάνει πολλαπλές λειτουργίες επεξεργασίας και επικοινωνίας και έχει πάρα πολλές δυνατότητες εξέλιξης. Η παρούσα υλοποίηση μπορεί να αποτελέσει οδηγό για παρόμοιες υλοποιήσεις στο μέλλον και παρουσιάζει τις προοπτικές των έξυπνων συστημάτων σε συνδυασμό με αισθητήρες.Smart sensors are used increasingly nowadays for environmental monitoring. A smart sensor is a system which includes apart from the sensor element a processor which enables local processing of the measurements. Within the framework of this master thesis a smart and flexible embedded system for measuring capacitance sensors has been designed and implemented. The system developed comprises of the sensor interface circuit, a LEON3 processor equipped with the necessary peripherals and a Linux operating system. The system implementation is done using a CYCLON series ALTERA FPGA, the Terasic DE2-115 development board and a custom board hosting the sensor elements. For the measurement of the sensors an interface circuit which converts the capacitance changes in frequency changes by using a specially designed ring oscillator is implemented. Subsequently, a programmable frequency counter featuring a variable measurement time window is used in order to provide flexibility to the measurement time, the accuracy and the range of elaborated frequencies. The interface circuit is connected to the internal data bus (AMBA bus) of LEON3 processor in order to behave as a typical peripheral of the processor and to achieve easy and efficient management from the application software. On the AMBA bus are also connected the standard peripherals of the system, namely, a SVGA touch screen display, a network module (ETHERNET) and a keyboard which give to the system additional capabilities and flexibility. With the embedded Linux operating system the system user can use a standard environment for the processing of the measurements and the communication with the sensors. The user can observe the results on the SVGA display or introduce editing commands from the keyboard. At the same time there is the possibility of a remote connection to the system and the transfer of the results to a remote computer. Programs written in the C programming language are developed for the processing of the measurements and the control of the interface circuit. A stand-allone system has been demonstrated exploiting the capabilities of the "touch screen" display mode and eliminating the need for the presence of a keyboard. The developed software module has the ability to perform sensor calibration and calculation of the mean value and the deviation of the measurements for all channels. To verify the system operation an array of four gas sensors has been used. The capacitive gas sensors consist of interdigitated electrodes and a polymer layer, whose electrical properties vary with the absorption of certain gases (analytes). The response of the proposed system compared to the capacitance measurements using a bridge for various concentrations of analytes has showed satisfactory agreement. The sensitivity of the system is also satisfactory as it can measure very small changes of capacitance resulting to a change of few tens of Hz in oscillation frequency. The system that was implemented can be used in numerous applications and can be adapted to various environments. By integrating the LEON3 processor which is flexible and configurable, hardware alterations can be easily made and the software can be adapted in order to add extra functionality. Overall, this thesis presents a flexible, stand-alone, easy-to-use and efficient smart system for the measurement of capacitive sensors, which includes multiple processing and communication functions and has many development possibilities. This implementation can be used as a guide for similar implementations in the future and shows the prospects of smart sensor systems

Design of agile signal conditioning circuits for microelectromechanical sensors

Microelectromechanical systems (MEMS) are used in many applications to detect physical parameters and convert them to an electrical signal. The output of MEMS-based transducers is usually not suitable to be directly processed in the digital or the analog domain, and they could be as small as femto farads in capacitive sensing and micro volts in resistive sensing. Consequently, high sensitivity signal conditioning circuits are essential. In this thesis, it is shown that both the noise and input capacitance are important parameters to ensure optimal capacitive sensing. The dominant noise source in MEMS conditioning circuits is flicker noise, and one of the best methods to mitigate flicker noise is the chopping technique. Three different chopping techniques are considered: single chopper amplifier (SCA), dual chopper amplifier (DCA), and two-stage single chopper amplifier (TCA). Also, their sensitivity and power consumption based on the total gain and sensing capacitance are extracted. It is shown that the distribution of gain between the two stages in the DCA and TCA has a significant effect on the sensitivity, and, based on this distribution, the sensitivity and power consumption change significantly. For small sensor capacitances, the highest sensitivity could be achieved by a DCA because of its ability to decrease the noise floor and the input sensor capacitance simultaneously. A novel DCA is proposed to reach higher sensitivity and reduced power consumption. In this DCA, two supply voltages are utilized, and the second stage is composed of two parallel paths that improve the SNR and provide two gain settings. This circuit is fabricated in the GlobalFoundries 0.13 μm CMOS technology. The measurement results show a power consumption of 2.66 μW for the supply voltage of 0.7 V and of 3.26 μW for the supply voltage of 1.2 V. The single path DCA has a gain of 34 dB with bandwidth of 4 kHz and input noise floor of 25 nV/√Hz. The dual path DCA has a gain of 38 dB with bandwidth of 3 kHz and input noise floor of 40 nV/√Hz. To be able to detect the signal near DC frequencies, another circuit is proposed which has a configurable bandwidth and a sub-μHz noise corner frequency. This circuit is composed of three stages, and three chopping frequencies are used to mitigate the flicker noise of the three stages. The simulated circuit is designed in the GlobalFoundries 0.13 μm CMOS technology with supply voltages of 0.4 V and 1.2 V. The total power consumption is of 6.7 μW. A gain of 68 dB and bandwidths of 1, 10, 100 and 1000 Hz are achieved. The input referred noise floor is of 20.5 nV/√Hz and the design attains a good power efficiency factor of 4.0. In the capacitive mode, the noise floor is of 3.6 zF for a 100 fF capacitance sensor

メモリをベースとしたマイコン用再構成可能デバイスとその応用に関する研究

13301甲第4625号博士（工学）金沢大学博士論文本文Ful