J Lim

Robotic smart house to assist people with movement disabilities

This paper introduces a new robotic smart house, Intelligent Sweet Home, developed at KAIST in Korea, which is based on several robotic agents and aims at testing advanced concepts for independent living of the elderly and people with disabilities. The work focuses on technical solutions for human-friendly assistance in motion/mobility and advanced human-machine interfaces that provide simple control of all assistive robotic systems and home-installed appliances. The smart house concept includes an intelligent bed, intelligent wheelchair, and robotic hoist for effortless transfer of the user between bed and wheelchair. The design solutions comply with most of the users’ requirements and suggestions collected by a special questionnaire survey of people with disabilities. The smart house responds to the users commands as well as to the recognized intentions of the user. Various interfaces, based on hand gestures, voice, body movement, and posture, have been studied and tested. The paper describes the overall system structure and explains the design and functionality of some main system components.

ON ASYMPTOTICALLY RELIABLE CLOSED SERIAL PRODUCTION LINES

A problem of sna(ysis and design of aerial production lines, cio~.d with respect to the number of carriers avsilable for parts transportation between operations, is formulated. An asymptotic solution is given for two machines-two buffers systems. A case study of s paint shop operation at an automobile assembly plant is described. It is shown that optimization of the system with respect to the number of carriers and the capacity of the feedback buffer may lead to a substantial improvement of systems perfornumce.

Self-tuning control of electromagnetic levitation systems

Abstract The mass uncertainty resulting from taking passengers, loading freight, and being disturbed by external forces is the main reason why the performance of electromagnetic levitation systems deteriorate. Thus, this paper proposes a self-tuning controller for electromagnetic levitation systems with unknown mass variations. The self-tuning controller is an extended version of gain scheduling for the general case of unknown scheduling parameters. Experimental results show the benefits of the scheme in cases of unknown mass variation compared with a conventional control methodology.

An integrated hybrid device for binary-phase-shift-keying subcarrier modulation

We propose an integrated optical/radio frequency (RF) hybrid device for binary-phase-shift-keying subcarrier modulation that is based on optical amplitude modulation and interference with phase delay. The device consists of two multiple-quantum-well (MQW) electroabsorption (EA) modulators branched with two multimode interference (MMI) couplers. When an RF carrier was applied to one modulator and a digital signal to the other one, the phase modulation of the RF subcarrier was realized.

Homogeneous, asymptotically reliable serial production lines: theory and case study

In this paper, a model of homogeneous, asymptotically reliable serial production lines is introduced, analyzed, and applied to performance evaluation of a modular paint shop at an automobile assembly plant. The results obtained indicate that the homogeneous, asymptotically reliable production lines are, on one hand, much simpler for analysis than the traditional models discussed in the literature for the last 25 years and, on the other hand, are sufficiently rich to reflect the behavior of real manufacturing systems. The asymptotic theory developed here gives analytical formulae for production rates as a function of system parameters and, therefore, can be used as an inexpensive tool for analysis and design of manufacturing processes in mass production systems eliminating, in certain cases, the necessity of complex and costly computer simulations.