Robotics and Interactive Systems Engineering (RISE) Laboratory

The RISE laboratory focuses in the design and development of Human-Machine Collaborative Systems (HMCS) and the study of human-machine haptics. We design and develop robotic systems that amplify and/or assist human physical capabilities when performing tasks that require learned skills, judgement, and precision. The systems seek to combine human judgement and experience with physical and sensory augmentation using advanced display and robotic devices to improve the overall performance. In haptic research, we are interested in understanding the human interaction with the physical (or virtual) world through their senses of touch. Our research aims at exploring the aspects of human dynamics and psychophysics that affect the human-machine interaction, such as force control and perception, and are essential to the advancement of future human-machine systems. The application of the research extends to numerous areas including medical and biomedical robotics, haptic (force-feedback) interfaces, simulation and training devices, and computer-aided manufacturing.

Virtual fixtures implemented on the Johns Hopkins University Steady-Hand Robot (Johns Hopkins University, 2007).

Current Research:

Closed-loop Vibration Feedback Device for Treatment of Apnea in Premature Babies

Once a baby is born he or she needs to breathe continuously to get oxygen. Commonly found in premature babies, the part of the central nervous system (brain and spinal cord) that controls the breathing is not fully developed, in which case the baby stops breathing. The medical term for this condition is apnea. A widely used clinical treatment for apnea is pharmacologic agents such as caffeine to prevent apnea. Another common way of treating apnea is to reinitiate breathing by rubbing the baby in sensitive areas, such as the baby's back or to soles of the feet, to stimulate the brainstem and causing the brain to resume breathing. Despite its effectiveness, manual rubbing can be inconsistent from one applicator to another and, in some case, can be too excessive and unsafe to the baby. The vibration feedback device is developed to provide a uniform and an adjustable amount of tactile sensation to replace the manual rubbing procedure. It can also be used as an initial treatment at the first sign of an apnea episode. A drop in the baby's heart rate and oxygen level are the common means used by doctors and nurses to determine the start of an apnea episode. In this device, the vital information outputted from a patient monitoring system is integrated to control the activation of the device in a closed-loop fashion.

Students: Mehrdad S. Mostoufi (ME, MS-2008), Mojgan Payombar (ME, MS-2009), Fernando Vera (BSEE, Summer Project 2009)

Medical Collaborators: Dr. Phuket Tantivit (Baptist Children's Hospital, Miami, Florida) and Dr. Rowena Cayabyab (LAC/USC Medical Center)

Gait Analysis of Below-knee Amputees

The project involves analysis of gait characteristics and evaluation of the effect of alignment variables such as prosthetic foot size and outward foot rotation on the rehabilitation outcome of individuals with bilateral below-knee amputation. The project objective aims at quantifying the key differences (or similarities) in the kinematic and kinetic characteristics of walking gait between bilateral and unilateral BK amputees. The research findings can lead to improvements in bilateral amputee gait patterns and to provide field guidance and possible robotic assistance for optimization of prosthetic alignment in bilateral amputees.

Student: MS Project for Mechanical Engineering available for Academic Year 2009-2010. Interested students should contact Prof. Marayong at marayong@csulb.edu.

Clinical Collaborators: Edmond Ayyappa, CPO and Dana Craig (VA Hospital, Long Beach)

Vision-based Robotic Guidance for Sealant Application

The project is in collaboration with Boeing engineers at the Center for Advanced Technology Support for Aerospace Industry (CATSAI) involving the development of a robotic workcell for automated sealant application.

Students: James Liu (ME, MS), Luis Caldron (BSME) and Martin Guirguis (BSEE)

Collaborators: Eric Whinnem, Angelica Davancens, and Branko Sarh (The Boeing Company), Profs. Bei Lu and Hamid Hefazi (CSULB)

Effect of Hand Dynamics on Virtual Fixtures for Compliant Human-Machine Interfaces

The goal of human-machine cooperative systems is to enhance user performance in tasks at the limits of human physical abilities. Cooperative systems combine the precision and the repeatability of a robot with the intelligence and experience of a human operator. Virtual fixtures are added to a cooperative system to guide the end-effector along desired paths in the workspace (guidance virtual fixtures) or to prevent the end-effector from entering undesired regions (forbidden-region virtual fixtures).  In cooperative manipulation systems, the user and the robot simultaneously grasp the end-effector/tool. The human user applies a disturbance force to the robot in order to achieve motion. Despite the high rigidity and non-backdrivability of an admittance-controlled system, small joint and link compliance visibly degrade virtual fixture performance. The virtual fixture location becomes incorrectly defined. In addition to the deflection of the robot due to voluntary motion, the inherent mechanical parameters of the human hand also generate dynamics that result in undesired involuntary motion. 

To investigate virtual fixture performance with hand dynamics, a 1-DOF admittance-controlled testbed was used. A spring element was added to simulate joint compliance. Two open-loop controllers were proposed to define a virtual fixture position that prevents the user from entering the true forbidden region: one that compensates for hand dynamics, and one that predicts overshoot based on the user's current velocity. The methods determine a 'safe' location of the virtual fixture that prevents the user from entering the true forbidden region. The virtual fixture can be viewed as a safety margin whereby its distance to the true forbidden region can vary depending on the dynamics of the system.