Kristofer S.J. Pister (Advisor)

Research Advised by Professor Kristofer S.J. Pister

Pister Group:  List of Projects | List of Researchers

PCB-Less Integration of a Robust Wireless MEMS Tactile Package

Dillon Acker-James
Kristofer S.J. Pister
2023

Creating a wireless tactile actuator the size of an aspirin will allow for more precise physical stimulation. This will lead to a more immersive virtual reality (VR) experience and better convey information via touch. Making this wireless tactile actuator can be accomplished by further utilizing the existing Si on Insulator (SOI) structure. Currently, a printed circuit board (PCB) is used for the sole purpose of assembly, however, further utilization of the Micro Electromechanical Systems (MEMS) SOI structure can allow the chip to operate as both the actuator and housing package. In...

Dillon Acker-James

Graduate Student Researcher
Electrical Engineering and Computer Sciences
Professor Kristofer S.J. Pister (Advisor)
M.S. 2022

Currently pursuing a doctoral degree after getting a Bachelors degree in Electrical Engineering from UC Santa Barbara, where my coursework and research in the Mishra lab focused on fabrication and device physics. In graduate school I'm working on the building blocks for a platform that will be able to house various sensors and devices in a dirty envirnment, like in contact with the human skin, and even fully submerged in an aqueous medium.

After an internship with Apple and Iota Biosciences I am driven to make MEMS-powered medical devices, enhanced and controlled by on-...

Frequency Compensated Crystal-Free 802.15.4 Wireless Radio

Alex Moreno
Kristofer S.J. Pister
2022

Crystal-Free radios are susceptible to frequency drifts due to temperature and voltage. Compensation for the frequency drift in the 2.4 GHz local oscillator due to voltage variation was demonstrated for a Crystal-Free radio while powered from a solar cell under 200 mW/cm2 of irradiation and a 0805 capacitor. Without compensation the local oscillator frequency would vary by 2.4 MHz while the 802.15.4 packets were transmitted resulting in a loss of 100B of the payload. With frequency drift compensation that oscillator frequency varied less than 300KHz and the full length 125B 802.15.4...

Nonlinear Dynamics of Lateral Electrostatic Gap Closing Actuators for Applications in Inchworm Motors

Ahad M. Rauf
Daniel Contreras
Ryan Shih
Craig Schindler
Kristofer S.J. Pister
2022

We present a nonlinear dynamics model for lateral electrostatic gap closing actuators (GCAs) operated in air and underwater. We factor in finger bending and the release phase’s initial velocity over prior work, and we systematically study the effect on GCA pull-in and release time by varying both the finger length and the release spring constant. Simulation results are then compared to experimental data with good conformity. We also apply this dynamics model to optimize electrostatic inchworm motors for drive frequencies up to 40 kHz and speeds up to 415 mm/s, over 11× faster than what has...

Jumping Silicon Microrobots With Electrostatic Inchworm Motors and Energy Storing Substrate Springs

Craig Schindler
2020

Jumping microrobots are a burgeoning area of autonomous microelectromechanical systems (MEMS). This dissertation presents background, theory, designs, and results of the first jumping microrobots fabricated in a silicon-on-insulator (SOI) process using electrostatic inchworm motors etched into the device layer silicon and energy storing springs etched into the silicon substrate. Substrate silicon is much thicker than device layer silicon, and can therefore store a lot more mechanical energy per unit area than can device layer silicon. New high force density electrostatic inchworm motors...

David Burnett

Alumni
Electrical Engineering and Computer Sciences
Professor Kristofer S.J. Pister (Advisor)
Ph.D. 2019

Oliver Chen

Alumni
Electrical Engineering and Computer Sciences
Professor Michel M. Maharbiz (Advisor)
Professor Kristofer S.J. Pister (Advisor)
Ph.D. 2022

Oliver graduated with the B.S. degree in Electrical Engineering from the California Institute of Technology in 2016. He is currently working on hydrogel actuated carbon fiber microelectrode arrays in as an EECS PhD student at the University of California, Berkeley with Prof. Michel Maharbiz. He is a recipient of the NSF Graduate Research Fellowship.

Oliver is interested in biomedical device technology related to both systems-level design and MEMS devices. This includes microfabrication and implementation of implantable devices, in particular, neural probes for brain-machine...

BSAC's Best: Fall 2022 Awards Announced

September 28, 2022

BSAC would like to thank all of the researchers who presented their research during BSAC's Fall 2022 Research Review on September 21st.

BSAC Industrial Members voted for the outstanding paper and presentations and the results are in. Please join BSAC in congratulating the recipients of the Fall 2022 Best of BSAC honors, Alex Moreno, Mutasem Odeh, and Vivian Wang!

Outstanding Presenter...

BPN959: Self-Righting for Micro Robots

Alexander Alvara
2022

In developing micro-robots for exploration in non-uniform terrain, it is often the case that robots fall over. This work seeks to provide a solution in the self-righting of autonomous micro-robots to overturn a 1cc, 1 gram cube microrobot with regular octahedral symmetry that has fallen on either of its four sides and overturning said microrobot once upside down. Our design currently consists of a 3-bar linkage in conjunction with an electrostatic inchworm motor. First-generation devices are in fab as of August. Hand analysis indicates that self-righting from any face should be...