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force-sensor
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Design and Implementation of a Tool Ttip Force Estimation Algorithm for Surgical Robotic Systems Using Proximal Sensor using Neural Network
, M.Sc. Thesis Sharif University of Technology ; Farahmand, Farzam (Supervisor)
Abstract
One of the most important problems in the field of robotic surgery is the measurement of the laparoscopic instrument Tip force. Many efforts have been made with the use of distal sensors to issues such as high cost and need to be disinfected, but the use of proximal sensors for estimating the Tip force of the tool is very rare, which can improve distal sensor problems.In this project, first, using data obtained from simulating a set-up for the Sina robot, two static MLP, and dynamic NARX neural networks are trained to evaluate the use of machine learning algorithms to determine whether the Tip force neural network can be used. Did the robot estimate Sina's surgeon? Then, by comparing this...
Designing a Loadcell for a Walker to Measure Upper Extremities’ Forces
, M.Sc. Thesis Sharif University of Technology ; Zohoor, Hassan (Supervisor)
Abstract
In this project, two bidirectional loadcell are designed and fabricated to be installed on a walker. Then upper extremities’ forces and moments have been obtained. Results can be used for rehabilitation purposes in Spinal Cord Injuries and Cerebral Palsy cases. The method used in this project is as follows: First, since the commercial multidirectional loadcells are too expensive, the loadcell (and an appropriate electronic board) are fabricated. Ultimately, a complete gait analysis by means of VICON motion analysis and using inverse dynamic method has been held to measure upper extremities’ forces and moments in the wrist, elbow and shoulder. The results for a person with Spinal Cord Injury...
Design and Manufacturing of a Propulsion Engine Thrust Forces Digital Test Stand in 3-DOF
, M.Sc. Thesis Sharif University of Technology ; Ghorbanian, Kaveh (Supervisor) ; Saeedi, Mohammad Hassan (Supervisor) ; Mozaffari, Ali Asghar (Supervisor)
Abstract
Measurements of magnitude and direction of thrust generated by a propulsion engine is important for verification of design, fabrication, assembely and or repare procedure used for a engine. Due to possible simplification in design calculations, human and machine errors in manufacturing process, the resulted thrust generated may be different from those values expected. Also, It is important to determine the dependency of magnitude and direction of thrust forces relative to tolerances and manufacturing processes. It is necessary to have thrust measuring stand with high accuracy with capability to measure the forces in different directions. A new digital engine test stand has been designed,...
Force Estimation of the Surgical Instrument tip by a 6-DOF Proximal Force Sensor Located at the End of the Sina Surgical Robot Instrument
, M.Sc. Thesis Sharif University of Technology ; Farahmand, Farzam (Supervisor)
Abstract
Measurement of laparoscopic instrument tip forces plays an important role in the research area of controlling robotic surgeries. The first attempts in this topic were estimating the tip forces using distal force sensors, but these methods were too expensive and required sterilization. On the other hand, proximal sensors do not suffer from the distal sensors problems, however, they were not used to estimate the instrument tip force in previous works. In this regard, the effectiveness of proximal sensors in this project was investigated. To do so, firstly, an appropriate plan for estimating the forces of the laparoscopic instrument’s tip was found using a proximal force sensor, located at the...
Experimental Investigations into Damage Detection Techniques in Concrete Beams
, M.Sc. Thesis Sharif University of Technology ; Joghataie, Abdolreza (Supervisor)
Abstract
A simply supported reinforced concrete beam has been built at the concrete laboratory of Sharif University of Technology. The cross section of the beam has been rectangular and all the reinforcing steel bars have been placed at the bottom of the beam. A progressive damage has been applied to the beam first by cutting the concrete cover and then by cutting the reinforcing bars one at a time. The beam has been tested using forced vibration test where an impact hammer has been used to apply the external load. The acceleration of the beam has been recorded based on which the FRFs and then the corresponding modal parameters have been determined. Finally natural frequencies, MAC, COMAC and mode...
Experimental Evaluation and Characterization of Piezo-film Force Sensors in Graspers
, M.Sc. Thesis Sharif University of Technology ; Farahmand, Farzam (Supervisor)
Abstract
Minimally invasive surgery (MIS) is a new surgical technique in which surgery is performed using smart instruments and viewing apparatus inserted through a very small incision rather than by making a large incision to expose, and afford access to the operation site. Piezo film force sensor can be used in MIS graspers for providing tactile data to overcome problems such as lack of sense of touch or to find hidden arteries.This thesis, investigates fundamental understanding of piezo film sensor especially when we want to connect these sensors to measurement units.Two different approaches for signal conditioning the sensor have been proposed and circuits have been fabricated. Several...
Optimal PID control of a nano-Newton CMOS-MEMS capacitive force sensor for biomedical applications
, Article Mechanics and Industry ; Vol. 15, issue. 2 , January , 2014 , p. 139-145 ; Ghafari, A. S ; Sharif University of Technology
Abstract
This paper presents closed loop simulation of a CMOS-MEMS force sensor for biomedical applications employing an optimal proportional-integral-derivative controller. Since the dynamic behavior of the sensor under investigation is nonlinear the iterative feedback tuning approach was proposed for optimal gains tuning of the proposed controller. Simulation results presented in this research illustrate that the proposed controller suppresses the undesired in-plane vibration induced by environment or gripper 40 times faster than the nonlinear controller proposed in the literature. To suppress the maximum input disturbance the maximum voltage was approximately 18 V which was less than the pull-in...
Optical flow-based motion estimation of ultrasonic images for force estimation in percutaneous procedures: Theory and experimental validation
, Article IECON Proceedings (Industrial Electronics Conference), 25 October 2012 through 28 October 2012 ; October , 2012 , Pages 1557-1560 ; 9781467324212 (ISBN) ; Jahed, M ; Sharif University of Technology
2012
Abstract
In recent years, there hass been a pronounced emphasis on percutaneous needle steering with the aid of advanced soft tissue modeling techniques. In this work an optical flow based motion estimation method is used to estimate the force applied to the needle by the soft tissue during percutaneous applications. The study considers Finite Element Model (FEM) of the tissue evaluated by the deformation data acquired through the optical flow method. To represent the soft tissue behavior, dynamic FEM with Rayleigh damping and viscoelastic models are used. The method is validated experimentally through offline evaluation of the ultrasonic images of the chicken breast punctured by a needle. The force...
Force controlled manipulation of biological cells using a monolithic MEMS based nano-micro gripper
, Article ASME International Mechanical Engineering Congress and Exposition, Proceedings (IMECE) ; Volume 2 , 2012 , Pages 193-201 ; 9780791845189 (ISBN) ; Ahmadian, M. T ; Sharif University of Technology
2012
Abstract
Nano-micro grippers are able to pick-transport-place the micro or nanometer -sized materials, such as manipulation of biological cells or DNA molecules in a liquid medium. This paper proposes a novel monolithic nano-micro gripper structure with two axis piezoresistive force sensor which its resolution is under nanoNewton. The results of the study have been obtained by the simulation of the proposed gripper structure in Matlab software. Motion of the gripper arm is produced by a voice coil actuator. The behavior of the cell has been derived using the assumptions in the literatures. Moreover, two simple PID controllers, one for control of the gripper motion and another for control of the force...
Designing instrumented walker to measure upper-extremity’s efforts: A case study
, Article Assistive Technology ; Volume 31, Issue 5 , 2019 , Pages 267-275 ; 10400435 (ISSN) ; Baniasad, M. A ; Arazpour, M ; Farahmand, F ; Zohoor, H ; Sharif University of Technology
Taylor and Francis Inc
2019
Abstract
The high prevalence of shoulder pain in using walkers in patients who have spinal cord injury (SCI). Also, the limited options available to economically measure grip forces in walkers, which drove the need to create one. This article describes a method to obtain upper-extremities’ forces and moments in a person with SCI by designing an appropriate instrumented walker. First, since the commercial multidirectional loadcells are too expensive, custom loadcells are fabricated. Ultimately, a complete gait analysis by means of VICON motion analysis and using inverse dynamic method has been held to measure upper-extremities’ efforts. The results for a person with SCI using a two-wheel walker in low...
Designing instrumented walker to measure upper-extremity’s efforts: a case study
, Article Assistive Technology ; 2018 , Pages 1-9 ; 10400435 (ISSN) ; Arab Baniasad, M ; Arazpour, M ; Farahmand, F ; Zohoor, H ; Sharif University of Technology
Taylor and Francis Inc
2018
Abstract
The high prevalence of shoulder pain in using walkers in patients who have spinal cord injury (SCI). Also, the limited options available to economically measure grip forces in walkers, which drove the need to create one. This article describes a method to obtain upper-extremities’ forces and moments in a person with SCI by designing an appropriate instrumented walker. First, since the commercial multidirectional loadcells are too expensive, custom loadcells are fabricated. Ultimately, a complete gait analysis by means of VICON motion analysis and using inverse dynamic method has been held to measure upper-extremities’ efforts. The results for a person with SCI using a two-wheel walker in low...
An extended algorithm for autonomous grasping of soft tissues during robotic surgery
, Article International Journal of Medical Robotics and Computer Assisted Surgery ; Volume 16, Issue 5 , 2020 , Pages 1-15 ; Farahmand, F ; Yazdian, S. M ; Mirbagheri, A ; Sharif University of Technology
John Wiley and Sons Ltd
2020
Abstract
Background: Autonomous grasping of soft tissues can facilitate the robotic surgery procedures. The previous attempts for implementing auto-grasping have been based on a simplistic representation of the actual surgery maneuvers. Method: A generalized three-zone grasp model was introduced to consider the effect of the pull force angulation on the grasp mode, that is, damage, slip, or safe grasp. Also, an extended auto-grasping algorithm was proposed in which the trigger force is automatically controlled against the pull force magnitude and direction, to achieve a safe and secure grasp. Results: The autonomous grasping experiments against a varying pull force in a phantom study indicated a good...
Active vibration control of a cmos-mems nano-newton capacitive force sensor for bio application using PZT
, Article Advanced Materials Research, San Diego, CA ; Volume 628 , 2013 , Pages 317-323 ; 10226680 (ISSN) ; 9783037855706 (ISBN) ; Selkghafari, A ; Zabiholah, A ; Meghdari, A ; Sharif University of Technology
Abstract
This paper reports the design of an optimal controller to prevent suppressvertical vibration due to undesired out of plane excitations generated by environment or gripper during manipulation for a CMOS-MEMS Nano-Newton capacitive force sensor applied for biomedical applications. Undesired out of plane excitations generated by environment or gripper during manipulation is the most prevalent source of vertical vibration in this type of sensors. To suppress the vibrational movement a PZT 5A is used as actuation mechanism. Discrete element method DEM model and Modal analysis were used to find dominant natural frequencies and mode shape vectors. To eliminate out of plane excitation an optimal...