Personal Computer Interface Research Articles

New technologies at the computer interface

Technology is developing rapidly, but not always as rapidly as one may be led to believe. What might we expect over the next decade from the key technologies that enable the personal computer interface?

Sensory Fabric for Ubiquitous Interfaces

Sensory Fabric is a technology that uses electrically conductive textiles to fabricate switches and sensors. In this article we examine how a number of broad device types, or form factors, can be reconfigured or made more ubiquitous by replacing their traditional interface hardware with Sensory Fabric. The implications of using a fabric solution are explored for handheld and personal devices, educational computing, and the personal computer interface. Each case study describes a number of technology demonstrator devices, using them to illustrate how some of the drawbacks of traditionally packaged interfaces can be countered. Sensory Fabric can replace small, cold, hard, heavy, and smooth interfaces with large area, warm, soft, lightweight, and tactile ones.

Application of the 1998 Version of the Aeroprediction Code

The U.S. Naval SurfaceWarfare Center aeroprediction code has been extended to the roll position of 45 deg (Ž ns in “ £ ” or cross-roll orientation) in addition to the roll position of 0 deg (Ž ns in “ ” or plus-roll orientation). It has also been extended to compute aerodynamics of nonaxisymmetricbodies based on an equivalent axisymmetric body. In addition, the nonlinear aerodynamic loads have been distributed over the body and lifting surfaces to provideamoreuseful tool forpreliminary structural analysis.Finally,new technologywas developed to improvethe predictionof axialforceat angleof attack.These new technologieshavebeen integrated into the1995Aeroprediction Code (AP95) and will be transitioned to legitimate users as the 1998 Aeroprediction Code (AP98). To make the AP98 more user friendly, an upgraded preand postprocessing, personal-computer interface was also developed. The theoretical methods of the AP98 are summarized, and a sample is shown of the comparisons of the AP98 predictions of static aerodynamics for several missile conŽ gurations to experimental data. Comparisons of theory andexperiment show that theAP98,on average, is at least as goodas theAP95and, in general,maybe slightlybetter.

The U.S. Digital Television Standard and its Impact on VLSI

The U.S. is in the final stages of establishing a Digital Television (DTV) transmission standard for digital terrestrial broadcasting in both HDTV and SDTV formats. The Grand Alliance prototype hardware has been extensively tested in both laboratory and field conditions and has exhibited outstanding performance. As of this writing, the Grand Alliance system has been officially recommended by industry to the FCC as the U.S. standard and final approval is expected from the FCC by the middle of 1996. The U.S. DTV standard will create a new market for digital consumer electronics products based on the standard, including DTV receivers, VCRs, camcorders and Personal Computer interface cards that will employ VLSI circuits to cost-effectively implement the products.

A computer-driven optical system for light stimulation in physiological experiments on retinal cells (electrophysiological applications)

This paper presents a new computerized control system for a dual-beam photostimulator. Electronic hardware and software were developed to set the optical filters and shutters for light stimulation of recorded retinal cells. Filters were set into stepper-motor-driven wheels which were controlled by specific boards and commanded through a new specially designed personal computer interface, all controlled by specially designed software. Each motor-controlling board was equipped with an electronic control system allowing command transduction and sequential generation of protocols. The electromagnetic shutters were controlled through a different board. The personal computer interface was set with a decodification system based on programmable logic devices. All electronic systems were organized in modular structures. The design performance was tested by measurement of the spectral and absolute sensitivity of retinal horizontal cells.

Theory, simulation, experimentation: an integrated approach to teaching digital control systems

This paper discusses the approach adopted by the authors for teaching an undergraduate course (lecture and laboratory) in digital controls. Theoretical material is developed in the lecture concerning the application of direct digital control (DDC) to an analog bench-scale system consisting of a DC motor and tachometer. A simulation of the closed-loop control system with embedded digital controller is developed and run by the students using the TUTSIM dynamic simulation language. Finally, students perform a laboratory experiment in which they write a program to control the actual system using a personal computer and inexpensive interface card. The combination of hands-on experience and computer simulation with the more traditional, theoretical lecture material provides a well-rounded learning experience that better prepares the students to implement digital control systems in the real world. >

Downhole temperature tool accurately measures well bore profile : Cloud, W B Oil Gas JV90, N29, 20 July 1992, P101–104

This paper reports that an inexpensive temperature tool provides accurate temperatures measurements during drilling operations for better design of cement jobs, workovers, well stimulation, and well bore hydraulics. Valid temperature data during specific wellbore operations can improve initial job design, fluid testing, and slurry placement, ultimately enhancing well bore performance. This improvement applies to cement slurries, breaker activation for slurries, breaker activation for stimulation and profile control, and fluid rheological properties for all downhole operations. The temperature tool has been run standalone mounted inside drill pipe, on slick wire line and braided cable, and as a free-falltool. It has also been run piggyback on both directional surveys (slick line and free-fall) and standard logging runs. This temperature measuring system has been used extensively in field well bores to depths of 20,000 ft. The temperature tool is completely reusable in the field, ever similar to the standard directional survey tools used on may drilling rigs. The system includes a small, rugged, programmable temperature sensor, a standard body housing, various adapters for specific applications, and a personal computer (PC) interface.

Personalizing ISDN

It is argued that making integrated services digital networks (ISDNs) more popular among personal computer users is essential for ISDN to prosper. Users in offices, businesses, and at home form a large potential ISDN market. Existing ISDN interface modules such as ISDN adapter boards for personal computers, are limited to ISDN features and can hardly handle the various needs of personal users. An ISDN interface module for personal computers must be designed to handle various applications and provide any-to-any communications. An ISDN personal computer interface developed to handle digital and analog communication protocols and flexibly combine resources is described. >

Computerized transcutaneous control of a multichannel implantable urinary prosthesis.

In the present paper we describe a personal computer interface of a multichannel implantable urinary prosthesis. This system is composed of two main parts: the first one is internal and consists of an implant using a 4-microns CMOS gate array chip controlling a wide variety of waveforms via eight monopolar channels. The second, an external controller featuring a versatile software, a PCB card plugged in a portable microcomputer, and a radiofrequency-coupled technique. This device is used to transmit the power, the data and the synchronization clock to the implant by a simple binary signal modulating a 20 MHz carrier. We also report the features of implant encapsulation and electrode design and fabrication. In the experimental phase, we studied the effect of early electric stimulation of the bladder during the spinal shock phase in the dog. We present the operative techniques that enabled us to perform chronic electrostimulation of the sacral roots and discuss the results.

A three-dimensional ultrasonic system for posture measurement

A time-efficient, cost-effective, and accurate system has been developed for measuring static three-dimensional joint coordinates in the laboratory. This system uses a personal computer interface to determine the distance between transmitters positioned at body joints and receivers positioned near the subject by measuring the travel time of ultrasound. Distance data are then converted to spatial coordinates and joint angles. The system can determine the location of 14 joints at one time. An experiment using three distances and five orientations between a transmitter and a receiver was performed to investigate the significance of measurement errors for the new system. The results showed that the standard deviation of the distance measurement was about 0.2 cm for single orientation conditions and was about 1 cm for all conditions tested. A second experiment using 11 transmitters and four receivers was performed to investigate the significance of measurement errors when determining three-dimensional coordinates. The results showed no significant difference between actual and measured coordinates. The system was then used to study the posture of a subject's upper extremity. Eight postures representing a variety of typical reaching tasks were examined. The results showed that the system was suitable for three-dimensional posture measurement.

Personal computer interface and software for the ZONAX microscope attachment controller

We describe the hardware and software of a general-purpose interface that permits a personal computer (PC) running MS-DOS to control cytometric devices, e.g., a scanning stage, shutters, and focus motor attached to a microscope. This note explains how to use the interface to convert the ZONAX microscope attachment controller from 8080-based hardware control to PC-based control.

Simulation modeling system for aquatic bodies

Basic principles and advantages of a user-friendly interactive modeling system (SIMSAB) are discussed. The system is designed as a personal-computer interface. The model is formulated in terms of a special flow-language, which is then automatically translated to produce portable Fortran programs that can be run on any computer. Additional blocks and processes can be put into the system by a user who knows Fortran. The system is intended for construction of compartmental models and includes a special hydrodynamic block to calculate wind-induced currents and to account for the material exchange between compartments.

Advanced energy management for home use

A novel system for controlling the electrical energy utilization in homes or small businesses is described. The developments include a telephone to power line carrier interface unit, a new electric meter that measures energy with variable pricing, and an energy controller that modifies use depending on price. The system provides for the marketing of electrical energy based on a supply/demand relationship using a real-time variable pricing scheme. A unique interface allows the customer to adjust energy utilization for heating or cooling, depending on comfort needs and the current price. Other electrical appliances such as electric water heaters can also be controlled automatically and optimally to achieve the lowest energy cost. A personal computer interface allows access to more detailed information and provides a means to personalize the system to a greater degree. The philosophy of this approach has been demonstrated, during field trials, to achieve the desired result of shifting some of the load from the peak to the valley. At the same time the users learned to use the system to lower their electric bills. >

Computer-controlled, patient-interactive, multichannel, implanted neurological stimulators.

Programmable implantable neurological stimulation systems with multiple electrodes have many advantages in clinical use, but time-consuming postoperative adjustment of stimulation parameters is a distinct disadvantage. A personal computer interface to standard commercial radiofrequency-coupled devices has been developed, permitting direct patient interaction to expedite this process. In addition, the system permits simulated multichannel operation and implementation of various modulation schemes.