Peng Peng Avatar

Peng Peng

Staff Development Engineer

Specialties: Sensing and actuating, data storage systems, micro-systems, material characterization,controls, embedded system design.

experience

Staff Development Engineer  
Seagate Technology, September 2014 to Present

Lead for contact detect technology and test development.

Sr. Development Engineer  
Seagate Technology, January 2012 to Present

• Performing detailed experiments to understand the physics of head-disk mechanical interactions. • Developing unique test methods and analysis / signal processing software to characterize head-disc mechanical interactions. • Data analysis and recommendations for head-disc mechanical and thermomechanical design improvements.

R&D Intern  
St. Jude Medical, May 2011 to August 2011

Invented novel sensing technology for implementation of transcatheter aortic valve implantation (TAVI). (invention disclosure submitted). Validated measurement system for optimal selection of tissue fiber orientation.

Doctoral Fellow  
University of Minnesota, September 2010 to June 2011

I was awarded Doctoral Dissertation Fellowship for the academic year of 2010 - 2011.

Graduate researcher  
Minimally Invasive Medical Technologies Center, April 2007 to May 2010

I have been trained extensively in the field of biomedical instrumentation. My research project has been sponsored by MIMTeC (Minimally Invasive Medical Technologies Center), a NSF Industry/University cooperative research center. Six leading medical device companies constitute the advisory board who continuously evaluate our research progress during the biannual meetings. This experience brought me a great opportunity to learn from experts in the medical device industry about their needs and constraints.

Teaching assistant  
University of Minnesota, January 2007 to December 2010

"Motion control laboratory", Senior level lab course involving lecturing, demonstrating and assisting lab effort of students “ Analog and digital control”, Graduate level course involving holding office hour, grading and assisting teaching

Graduate research assistant  
Advanced Controls and Micro-sensors Laboratory, University of Minnesota, September 2006 to December 2011

My research experiences are as follows. Biomedical Sensing and Actuating Instrumentation • Invented flexible micro tactile sensor array for tissue properties characterization • Developed three dimensional force sensor array on a flexible substrate • Prototyped handheld touch probe for tissue elasticity measurement • Invented piezoelectric resonance sensor for contact force measurement • Instrumented wireless sensing units for capacitance measurement of a capacitor array using microprocessors, multiplexer, capacitance-to-digital converter IC and RF transceivers • Modeled and simulated contact behavior at the sensor – tissue interface using ANSYS© Mechanical MEMS, Nanofabrication and Materials Characterization • Invented ultra-thin polymer layer fabrication, bonding, alignment, and metallization technique • Developed surface micromachining process for a CVD silicon nitride based capacitive sensor array • Fabricated MEMS sensors using photolithography, evaporation, sputtering, chemical vapor deposition(CVD), dry-etching, wet-etching, critical point dryer and wafer dicing • Trained in scanning electron microscopy (SEM), atomic force microscopy (AFM), confocal microscope, surface profiler, nano-indenter and ellipsometer Embedded System and Signal Processing • Simulated an active audio noise cancellation system using Xilinx Spartan- 3E FPGA platform • Developed capacitance measurement and control units using TI MSP430 microprocessor kit • Developed recursive least square algorithm for estimation of sensor measurement Surface Treatment and Chemical Coating Technology • Developed self-assemble monolayer process for hydrophobic surface treatment • Developed oxygen plasma process for hydrophilic surface treatment • Trained in wafer-based dispersions for carbon nanotubes using cationic and anioic surfactants

education

University of Minnesota-Twin Cities  
Doctor of Philosophy, Mechanical Engineering, Jan, 2006 to Jan, 2011
Thesis title: Novel MEMS Tactile Sensor for Tissue Stiffness Measurement

University of Minnesota-Twin Cities  
Master Of Science, Electrical Engineering, Jan, 2006 to Jan, 2009


University of Science and Technology of China  
Bachelor of Engineering, Automation, Jan, 2002 to Jan, 2006


Certifications

  • NI Certified LabVIEW Associate Developer
    National Instruments 
    April 2013

patents

Sensing Tissue Properties  (PCT/US2010/030213)    
Inventors: Peng Peng, Rajesh Rajamani, A Serdar Sezen, Arthur G Erdman.  Issued April 01, 2010  in us

publications

Flexible tactile sensor for tissue elasticity measurements     
Published by (IEEE/ASME Journal of Microelectromechanical Systems)
Authors: Peng Peng, Rajesh Rajamani, Arthur G. Erdman.  Published January 01, 2009

This paper presents a novel tactile sensing technique for tissue elasticity measurements. A prototype flexible tactile sensor has been successfully fabricated using polydimethylsiloxane (PDMS) as the structural material. The proposed sensor comprises an array of capacitors with no active elements used. By varying the sizes of sensing membranes within the capacitors, different stiffnesses of sensing diaphragms can be achieved. The elasticity of the targeted object can be thereafter measured based on the relative deflections of the sensing diaphragms. The fabricated sensor has been calibrated by an off-the-shelf polymer durometer hardness selector pack. The results show sensing resolution of 0.1MPa for elasticity measurement and a force sensing resolution as small as 5mN. This flexible tactile sensor can be embedded on the distal portions of various endoscopic instruments for in-vivo tissue elasticity measurements.

Novel MEMS stiffness sensor for force and elasticity measurements     
Published by (Sensors & Actuators A: Physical)
Authors: Peng Peng, A Serdar Sezen, Rajash Rajamani, A G Erdman.  Published March 01, 2010

This paper presents the design, mathematical model, fabrication and testing of a novel type of in-vivo stiffness sensor. The proposed sensor can measure both stiffness and contact force. The sensing concept utilizes multiple membranes with varying stiffnesses and is particularly designed for integration with minimally invasive surgery (MIS) tools. In order to validate the new sensing concept, MEMS capacitive sensors are fabricated using surface micromachining and each fabricated sensor has a 1mm x 1mm active sensor area. Finally, the sensors are tested by touching polymers of different elastic stiffnesses. The results are promising and confirm both the capability of the sensor for measuring of both force and tissue compliance.

Handheld micro-tactile sensor for elasticity measurement     
Published by (IEEE Sensors Journal)
Authors: Peng Peng, Rajesh Rajamani.  Published 

This paper presents an ultra-low-cost MEMS tactile sensor that can provide elasticity measurement of a variety of target objects. This senor can be integrated on a handheld probe or on minimally invasive surgical tools for in-vivo tissue elasticity measurement. The tactile sensor consists of a pair of contact bumps that have different values of stiffness. Two capacitive force gauges are integrated underneath the bumps. The sensor readout is composed of two channels of capacitance values and the ratio of these capacitance values can be used to calculate the elasticity of target objects. To obtain reliable measurement of capacitance ratios, an estimation algorithm is developed by using a recursive least squares method with adaptive forgetting factors. Experimental characterization of the sensor shows that this tactile sensor provides reliable elasticity measurement of polymer specimens and quickly detects changes in elasticity.

Novel MEMS stiffness sensor for in-vivo tissue stiffness measurements     
Published by (31st Annual International Conference of the IEEE Engineering in Medicine and Biology Society)
Authors: Peng Peng, A Serdar Sezen, Rajesh Rajamani, A G Erdman.  Published 

Flexible tactile sensor for measurements for Young's modulus and shear modulus of elasticity     
Published by (Proceeding of Transducers 2011 (The 16th International Conference on Solid-State Sensors, Actuators )
Authors: Peng Peng, Rajesh Rajamani, Xun Yu, Arthur G. Erdman.  Published January 01, 2011

This paper presents a tactile sensor capable of in-vivo measurement of Young's modulus and shear modulus of elasticity for soft tissue and other materials. The shear modulus measurement is enabled by using a quad electrode structure in each sensing cell.

Flexible micro-tactile sensor for normal and shear elasticity measurements     
Published by (IEEE Transactions on Industrial Electronics)
Authors: Peng Peng, Rajesh Rajamani, Arthur G. Erdman.  Published January 01, 2011

This paper presents a tactile sensor capable of measurement of Young’s modulus and shear modulus of elasticity for polymers, soft tissue and other materials. The sensor is built by using polydimethylsiloxane (PDMS) as the structural material. A number of sensing cells of different stiffnesses are used in each sensor. The Young’s modulus of the targeted object can be measured based on the relative deflections of adjacent sensing cells. The shear modulus measurement is enabled by using a quad electrode structure in each sensing cell. Experimental results show sensing resolution of 0.1MPa for Young’s modulus measurement in the range of 0.1MPa to 1MPa, and 0.05MPa for shear modulus measurement ranging from 0.05MPa to 0.2MPa. This flexible tactile sensor can be integrated on the end-effector of robotic arms to achieve tactile sensing feedback. The proposed sensing technology can also be utilized for fast measurement of both Young’s modulus and shear modulus for industrial applications that involves measuring mechanical properties of materials.

Measurement of tension in a string using an array of capacitive force sensors     
Published by (IEEE Sensors)
Authors: Peng Peng, Kalpesh Singal, Rajesh Rajamani.  Published 

The measurement of tension in strings and soft tissues is of critical importance in many applications, including orthopedic surgeries. Various sensors have previously been designed for the measurement of tension, but they all require either attachment of the sensor to the string or the use of an external-inertial reference. This paper presents two new sensors to estimate tension in strings without the need for attaching any devices on the string or a need for an inertial reference. Both sensors employ an array of three capacitive force measurement devices and estimate the tension based on these three readings. Experimental data show that the sensors can measure tension values up to 100 N on a bench-top test rig.