User Console Research Articles

A controller for brushless direct current electric motors. Part 2. Software

A universal controller for brushless direct current (BLDC) motors was designed in the presented article. The system is controlled from the user console where operating parameters are set by the user. Signals are transmitted by cables to microcontrollers which control and monitor electric motors. Microprocessors communicate via a data bus. The controller contains the user console module and the motor control module. The user console module generates commands, and motors are controlled and monitored by the control module. Motor control modules operate independently, and each brushless motor has a dedicated control module. Brushless motors can be controlled in bipolar or unipolar mode. The control method is selected by the operator. The user console and motor controllers communicate via the I²C bus.

A controller for brushless direct current electric motors. Part 1. Electrical and electronic design

A universal controller for brushless direct current (BLDC) motors was designed in the presented article. The system is controlled from the user console where operating parameters are set by the user. Signals are transmitted by cables to microcontrollers which drive and monitor electric motors. Microprocessors communicate via a data bus. The controller contains the user console module and the motor control module. The user console module generates commands, and motors are controlled and monitored by the control module. Motor control modules operate independently, and each brushless motor has a dedicated control module. Brushless motors can be controlled in bipolar or unipolar mode. The control method is selected by the operator. The user console and motor controllers communicate via the I²C bus.

Toward Cloud-Based Distributed Interactive Applications: Measurement, Modeling, and Analysis

With the prevalence of broadband network and wireless mobile network accesses, distributed interactive applications (DIAs) such as online gaming have attracted a vast number of users over the Internet. The deployment of these systems, however, comes with peculiar hardware/software requirements on the user consoles. Recently, such industrial pioneers as Gaikai, Onlive, and Ciinow have offered a new generation of cloud-based DIAs (CDIAs), which shifts the necessary computing loads to cloud platforms and largely relieves the pressure on individual user’s consoles. In this paper, we aim to understand the existing CDIA framework and highlight its design challenges. Our measurement reveals the inside structures as well as the operations of real CDIA systems and identifies the critical role of cloud proxies. While its design makes effective use of cloud resources to mitigate client’s workloads, it may also significantly increase the interaction latency among clients if not carefully handled. Besides the extra network latency caused by the cloud proxy involvement, we find that computation-intensive tasks (e.g., game video encoding) and bandwidth-intensive tasks (e.g., streaming the game screens to clients) together create a severe bottleneck in CDIA. Our experiment indicates that when the cloud proxies are virtual machines (VMs) in the cloud, the computation-intensive and bandwidth-intensive tasks may seriously interfere with each other. We accordingly capture this feature in our model and present an interference-aware solution. This solution not only smartly allocates workloads but also dynamically assigns capacities across VMs based on their arrival/departure patterns.

OpenGnSys: A novel system toward centralized deployment and management of computer laboratories

Operation and status of computers in teaching laboratories can significantly influence motivation and expectation of students, thus resulting in a reduction of their academic progress. To address this issue, this paper presents a complete deployment, management, and maintenance tool for operating systems (OS) called OpenGnSys. As part of a larger educational project, OpenGnSys has been tested in a real computer lab with the aim of improving teaching and learning in classroom. OpenGnSys provides an easy and intuitive way to administrate labs from a graphical user console with remote backup functions. Its design comprises a two-node high availability cluster for both hardware infrastructure and computer services, thus ensuring the availability of essential lab equipment. Additionally, this paper proposes a methodology for the installation, maintenance and quality control for computers and laboratory equipment by site acceptance tests (SATs). The main interest of the proposed SATs lies in representing a standardized procedure, which intends to facilitate and determine the degree of compliance with lab specification and operation services. In order to address the research problem, we analyzed OpenGnSys including lab technicians, 94 students and 7 teachers on Computer Science along three academic years. As a result, the OpenGnSys management system has demonstrated the effectiveness of the followed methodology and positively influenced the students' academic progress.

Rapid prototyping of active measurement tools

We propose a platform for the rapid prototyping of active measurement tools to collect network characteristics. Our proposal, named FLAME (Flexible Lightweight Active Measurement Environment), allows the prototyping of active measurement tools that depend or not on cooperative destination nodes. FLAME provides its users with basic active measurement primitives—corresponding to basic building blocks—upon which sophisticated active measurement tools can be prototyped quickly, practically, and efficiently through scripts in the Lua scripting language. This platform is based on the distributed deployment of measurement agents in some network nodes. These agents can send and receive probes in response to Lua scripts sent by a user console. Such agents also publish the measurement data in a standardized way in a repository that a central manager keeps, thus simplifying the management and analysis of such data. We validate the FLAME platform as well as show its flexibility and accuracy through experiments on a local testbed and also on Planet-lab. We also evaluate the proposed platform as compared to previous work in terms of the easing of development due to prototype scripting as well as the achieved memory footprint. In conclusion, we discuss different possibilities for further developments built upon the basic functionality of the proposed platform.

The da Vinci Research Interface

The da Vinci research interface allows third party developers and research collaborators to retrieve a real-time stream of kinematic and user event data from the da Vinci Surgical System during clinical use. This data includes the motion of all master and slave manipulators, as well as a number of user console events such as button and pedal activations. This paper provides a brief outline of the technical scope of the da Vinci research interface, as well as some discussion of the criteria for accessing this interface, and requirements for establishing a research partnership with Intuitive Surgical Inc.

Simulation of multi-organisational coordination in emergency response for system resiliency

This paper presents a multi-agent and human-in-the-loop simulator for emergency response in disasters. We identified and categorised various typical situation-oriented rules using interviews and questionnaire surveys of emergency responders who hold positions as local government officials, police and nuclear experts, as well as observed emergency exercises during various disasters. These factors were then implemented into a previously developed organisational model of intra- and inter-agency communication and coordination for emergency response. Based on this model, a multi-agent simulator for organisational behaviour in emergency response was developed. In addition, a user console on an identical simulation platform was constructed and integrated with the multi-agent simulation. Users can exchange messages through the console by using the same ontology and message format as those used by computer agents. Test simulations were executed and the results confirmed that the multi-agent, human-in-the-loop simulation creates various complicated situations that are similar to actual emergency situations and, therefore, could be a strong candidate for education, training and exercises in disaster response.

The Reconstruction of Konrad Zuse's Z3

Konrad Zuse's Z3, built in Berlin from 1938 to 1941 was destroyed during World War II. The reconstruction project started in 1994. A functional replica was built and unveiled at a conference commemorating the 60th anniversary of the public presentation of the original machine in 2001. The reconstruction project includes several Java simulations of components of the whole machine and a 3D functional simulation of the Z3 and its user console. This article is our account of our journey into history, about how we carried out the reconstruction, and why it is important that historians of computing, and computer scientists, pursue such projects.

A Vision-Based Approach for Estimating Contact Forces: Applications to Robot-Assisted Surgery

The primary goal of this paper is to provide force feedback to the user using vision-based techniques. The approach presented in this paper can be used to provide force feedback to the surgeon for robot-assisted procedures. As proof of concept, we have developed a linear elastic finite element model (FEM) of a rubber membrane whereby the nodal displacements of the membrane points are measured using vision. These nodal displacements are the input into our finite element model. In the first experiment, we track the deformation of the membrane in real-time through stereovision and compare it with the actual deformation computed through forward kinematics of the robot arm. On the basis of accurate deformation estimation through vision, we test the physical model of a membrane developed through finite element techniques. The FEM model accurately reflects the interaction forces on the user console when the interaction forces of the robot arm with the membrane are compared with those experienced by the surgeon on the console through the force feedback device. In the second experiment, the PHANToM haptic interface device is used to control the Mitsubishi PA-10 robot arm and interact with the membrane in real-time. Image data obtained through vision of the deformation of the membrane is used as the displacement input for the FEM model to compute the local interaction forces which are then displayed on the user console for providing force feedback and hence closing the loop.

Design and application of a novel brain slice system that permits independent electrophysiological recordings from multiple slices

We describe a novel brain slice system ‘SliceMaster’ that allows electrophysiological recordings from eight brain slices independently. The system consists of two autonomous units each supporting four modular brain slice chambers enabling high signal-to-noise ratio recordings, each chamber has one stimulation electrode, one recording electrode, a twin camera system and a solution application system. The positioning of both electrodes and cameras are controlled from a remote user console. The software both acquires and performs on-line analysis of the data. We have demonstrated utility of this system in obtaining recordings of spontaneous firing activity and evoked synaptic activity from mouse hippocampal slices, with reduced variability within and between experiments. Furthermore, we show recordings of population spikes from the perirhinal cortex, indicating applicability of this system for further brain regions. In addition, stable recordings could be maintained until recording was terminated after 3 h, permitting investigation of the induction and maintenance of synaptic plasticity. Recordings of spontaneous and synaptic activity, and effects of pharmacological and electrophysiological manipulation, were consistent with reports using conventional methods. However, the described system permits concurrent and independent recordings from eight brain slices, thus improving throughput, statistical design, and reducing animal use.

A Vision‐Based Approach for Estimating Contact Forces: Applications to Robot‐Assisted Surgery

The primary goal of this paper is to provide force feedback to the user using vision‐based techniques. The approach presented in this paper can be used to provide force feedback to the surgeon for robot‐assisted procedures. As proof of concept, we have developed a linear elastic finite element model (FEM) of a rubber membrane whereby the nodal displacements of the membrane points are measured using vision. These nodal displacements are the input into our finite element model. In the first experiment, we track the deformation of the membrane in real‐time through stereovision and compare it with the actual deformation computed through forward kinematics of the robot arm. On the basis of accurate deformation estimation through vision, we test the physical model of a membrane developed through finite element techniques. The FEM model accurately reflects the interaction forces on the user console when the interaction forces of the robot arm with the membrane are compared with those experienced by the surgeon on the console through the force feedback device. In the second experiment, the PHANToM haptic interface device is used to control the Mitsubishi PA‐10 robot arm and interact with the membrane in real‐time. Image data obtained through vision of the deformation of the membrane is used as the displacement input for the FEM model to compute the local interaction forces which are then displayed on the user console for providing force feedback and hence closing the loop.

A high-resolution multipurpose FT nmr spectrometer

An FT nmr spectrometer is by definition complex : many users and uses, at least three nuclear frequencies, numerous excitation patterns and sophisticated data-processing methods. Hence such machines are often unwieldy for the designer, builder, operator and end-user. We have set ourselves the goal of building a machine which can be operated with hardly any training by users, and which can be easily maintained or modified by others than the building team. The design is based on the repetitious use of simple methods. In the analogic part, the three nuclear channels are built alike, pulsing, phase-switching etc. are all done at the intermediate frequency, and most systems are broad-band, notably the transmit/receive switches. A bus carries the logical controls. Receiver recovery time is 8 μs, enabling solid-state type, broad lines to be measured. The spectrometer is multinuclear. Quadrature detection is used. A special design simplifies probe building. The interface between the analogic part and the computer is also built around a bus. It is easily programmed, and it can be extended. Data are accumulated as 32-bit words, thus avoiding memory saturation. The acquisition, under computer control, is easily programmed but limited to a total spectral width of 28.5 kHz. The programs, written in FORTRAN, make extensive use of subroutine libraries which manage the interactions of the computer and its peripherals, notably the spectrometer interface and the user's console. The programs are thus reduced mostly to CALL statements. They are easy to understand, maintain or create. User-software communications are fast, extensive, in English. Words are keyed-in by their first letter and printed in full. No mnemonics are used. Lists of available commands, program nesting and abundant information provided by the programs minimize the dependence on introductory manuals. Essential for the speed and ease of communications is the use of a CRT console, with graphics capability.

Generations One and Two: Nuclear Physics Experience with On-Line Computers

The installation of an SDS 910 computer at the Brookhaven 60" Cyclotron four years ago represented one of the first on-line computer applications in nuclear physics. The experience gained with this computer and its application to the design of a second-generation system indicates some of the problems inherent in a computer-oriented laboratory as well as possible solutions. The development of a new system has been undertaken jointly at the Rutgers/Bell Accelerator at which the 910 system is now located and at the Brookhaven Cyclotron, in view of the common data handling problems at the two laboratories. In its present location the 910 is used 90% of the time by staff and students for data collection, leaving very little time for data analysis and programming. Experience indicates that these activities each require at least as much time as data collection in order to use the accelerator to best advantage. The solution to this problem is to use an advanced time-sharing computer to handle all applications from a number of user consoles. By using a fast disc file both to store data being accumulated and to furnish display information directly to the oscilloscopes, the central processor will be freed most of the time for program compiling and computation. Program development will be greatly speeded by the storage of source programs on the disc, with conversational editing and debugging from the consoles.