Welcome to the website of the Geometric and Physical Computing group at Northeastern University’s College of Computer and Information Science. We develop algorithms, software, and hardware to address open problems in robotics, perception, manufacturing, and human-machine interfaces.
PI: Marsette Vona
Location: 214 West Village H, 440 Huntington Avenue, Boston MA (directions, map)
February 29, 2012: Prof. Vona was featured on the NEU homepage today with a story about his recently awarded NSF CAREER grant to study 3D perception combined with compliant contact.
January 29, 2012: Our new website for OHMM is now live with details on the robot, photos, hardware designs, software sources, and curriculum materials.
December 21, 2011: Our new course CS5350 Applied Geometric Representation and Computation was approved to be taught in S12. This will be an adaptation of our prior topics course taught as CS7380 in F10.
December 7, 2011: We held the grand finale to our new introduction to robotics course CS4610 today, with undergrad groups demonstrating impressive autonomous algorithms to collect objects among obstacles using vision and map navigation, and grad students showing implementations of visual-servo line following. Ten of our new OHMM robots were used throughout the course. Student feedback included: “Best/most informative class I’ve ever taken”, “The combination of in-class analysis of ideas and out-of-class hands on lab assignments truly embodies the ‘co-op’ mentality of Northeastern’s overall curriculum”.
December 5, 2011: 
All the main hardware systems have now been validated on our Open Hardware Mobile Manipulator (OHMM), a new small low-cost teaching robot. These include differential drive mobility with quadrature encoder feedback; on-board low- and high-level processors (8bit/20MHz and 32bit/1GHz); wifi and ethernet connectivity; 5A-h NiMH battery; optional AC supply; a 3-DoF arm with gripper; and a mast supporting both a monocular camera and Kinect. All components for the robot are either available off-the-shelf or are fabricated with hand tools, 3D printing, and laser cutting. No custom machining is required. We will be releasing all design files and sourcecode for the robot under open source licenses.
November 16, 2011: We were pleased to host Rob Platt for a visit and seminar today. Rob is currently a research scientist working with Russ Tedrake, Leslie Kaelbling, and Tomas Lozano-Perez at MIT, and he will start as assistant professor at SUNY Buffalo in 2012.
September 27, 2011: We presented our new work on perception in unmodeled environments in the contact and deformation session at IROS in San Fransisco. Prof. Vona was a co-chair of the session along with Jeff Trinkle from RPI.
June 24, 2011: Our new paper “Curved Surface Contact Patches with Quantified Uncertainty” has been accepted for publication at the IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS) 2011. See videos and get the source code here.
June 23, 2011: 
Detailed mechanical design is now complete for our new robot, the Open Hardware Mobile Manipulator “Ohmm”, an open design for a low-cost but capable platform for learning modern algorithms and software techniques in manipulation and locomotion. It combines a differential-drive base, low and high-level onboard processors, a mast with several camera options, bump and distance sensors, and a compliant 3DoF manipulator arm with precision sensing.
April 21, 2011: We were pleased to host our collaborator Jeff Norris of the NASA/Caltech Jet Propulsion Laboratory for a visit and seminar today.
April 20, 2011: 
We have released a new software package called the Surface Patch Library (SPL) which includes models of 10 types of curved surface patches and an algorithm to fit them to potentially noisy range sensor data. Uncertainty is quantified throughout using covariance matrices. Some of the mathematical foundations of the system are described in this paper.
March 19, 2011: Our new introduction to robotics course CS4610 was approved to be taught in F11. This will be an exciting and challenging course where students will learn to modern robotics software techniques for mobile manipulation. Undergraduate enrollment is now open. There will also be a concurrent graduate version of the course.
January 27, 2011: We were pleased to host Justin Werfel of Harvard’s Wyss Institute for a visit and seminar today.
December 20, 2010: 
The first offering of our new course Applied Geometric Representation and Computation has just completed as topics course CS7380. A focal point this term was studying Klein and Murray’s work in Parallel Tracking and Mapping (PTAM). Student feedback was very positive: “The well designed syllabus, the course’s projects and the Professor’s/students’ presentations made the class very interactive in a way that everybody became very enthusiastic about the class. In addition this class helped me a lot with my research.”
December 15, 2010: We were pleased to host Greg Aloupis of Universite Libre de Bruxelles for a visit and seminar today.
November 18, 2010: John Reif of Duke University visited NEU CCIS today as part of our Distinguished Speaker Lecture series.
February 4, 2010: We were pleased to host Joseph Durham of UCSB for a visit and seminar today.
March 24, 2010: Prof. Vona gave a presentation in the nuACM lecture series today. Video here.
We are currently focusing on several problems in perception and control for bipedal and humanoid locomotion on very uneven 3D terrain. These were motivated by some of our prior work in compliant climbing and stair-stepping, which led us to consider how compliant and proprioceptive motion strategies can be combined with on-line perception of uncertain contact surfaces.
We are developing a set of curved and flat patch models to represent both nearby environment surfaces and contacting surfaces on a robot including foot soles and fingertips. Unlike prior approaches (e.g. algebraic surfaces) we use geometrically meaningful minimal parameterizations, we quantify uncertainty in patch shape and pose, and we include the patch boundary. Fast perceptual algorithms can detect instances of these patches around a moving robot, and as patches are observed and re-observed a spatial map can be built to support motion planning and control.
We recently released a new software package called the Surface Patch Library (SPL) which includes models of 10 types of curved surface patches and an algorithm to fit them to potentially noisy range sensor data. Uncertainty is quantified throughout using covariance matrices. Some of the mathematical foundations of the system are described in this paper.
A primary advantage of bipedal locomotion (vs wheels or tracks) is the potential to negotiate highly faceted 3D trails as humans do. An understanding of how to address this challenge will help enable intelligent prosthetics, human locomotion aids, and robots that can safely follow and assist humans in rugged terrain.
Sensing and mapping upcoming footholds in real time seems inescapable for this task. Though some recent robots have achieved impressive advances in mechanics and control for walking on rough terrain, they largely operate without significant forward-looking perception. Work to implement these perceptual functions, or even to study human perception in this task, is still in its infancy. We are thus developing a body-worn sensor system to acquire quantitative datasets observing human locomotion on rocks and correlated perceptual behavior, including gaze direction and foot-sole tactile sensing.
We are studying humanoid locomotion on terrain composed of sloped planar facets as an in-lab approximation for hiking on a rocky trail. We are considering a four-phase strategy: (1) acquisition of a next-facet pose estimate by range sensors, including a quantified estimate of uncertainty; (2) passive compliant foot placement based on this estimate, with leg stiffness modulated according to the degree of uncertainty; (3) post-contact proprioception (joint angle sensing) to reduce uncertainty; (4) follow-through of torso and trailing leg with up-modulated leg stiffness for control.
Though most existing humanoids have high-impedance joint actuators, recently a few low-cost mini-humanoids have become available which enable modulation of actuator stiffness by a combination of passive backdriveability and on-line adjustment of servo position loop proportional gain. Our experimental apparatus is based on this approach to control joint compliance.
Mouseover each image for a description, click for details.
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Marsette Vona Assistant Professor Group Founder and Principal Investigator |
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Dimitrios Kanoulas Ph.D. Candidate |
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Dohyong Koh Ph.D. Student |
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Morteza Delgir Ph.D. Student |
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Henry Roth Ph.D. Student |
Past and present research funding:
NSF CAREER: Reliable Contact Under Uncertainty: Integrating 3D Perception and Compliance (PI Marsette Vona)
NSF MRI-R²: Development of a Second-Generation Applications-Driven Wireless Sensor Networking Instrument (PI Guevara Noubir)
The best way to contact us is to send email to Marsette Vona.
If you will be visiting us, our lab is located in 214 West Village H, 440 Huntington Avenue, Boston MA (map). Take the MBTA Green Line E train to the Northeastern stop, then walk one block west on Huntington Ave. WVH is the glass-facade building at the corner of Parker and Huntington, diagonally southeast across Huntington from the Museum of Fine Arts.
Our mailing address is
360 Huntington Ave
202 WVH, attn Marsette Vona
Boston, MA 02115
Some of our colleagues and collaborators include
