Automatic Control Mode Research Articles

Rare-earth permanent magnet machine system of electric vehicle

In order to reach the driving request of electric vehicle(EV),the EV power-driven system is researched,which takes rare-earth permanent magnet machine as key technology. A bran-new automatic control mode of traction motor is researched and applied in the EVs.At the same time a kind of planetary gear transmission case is designed,which has simple structure and excellent characteristics.Otherwise it is controlled by wire.And the influences on EV longitudinal amenity are analyzed,which are from the moment characteristics of the motor driving system.By the strategy of automatic weak- magnetism control,the motor system can fit all the need for driven system of EV.Matching the motor with double shii~s, guarantee the drive system work efficiency on a high level when the EV is in the max speed.

Genetic polynomial regression as input selection algorithm for non-linear identification

The performance of non-linear identification techniques is often determined by the appropriateness of the selected input variables and the corresponding time lags. High correlation coefficients between candidate input variables in addition to a non-linear relation with the output signal induce the need for an appropriate input selection methodology. This paper proposes a genetic polynomial regression technique to select the significant input variables for the identification of non-linear dynamic systems with multiple inputs. Statistical tools are presented to visualize and to process the results from different selection runs. The evolutionary approach can be used for a wide range of identification techniques and only requires a minimal input and a priori knowledge from the user. The evolutionary selection algorithm has been applied on a real-world example to illustrate its performance. The engine load in a combine harvester is highly variable in time and should be kept below an allowable limit during automatic ground speed control mode. The genetic regression process has been used to select those measurement variables that have a significant impact on the engine load and that will act as measurement variables of a non-linear model-based engine load controller.

MagScrew TAH - AN UPDATE

Purpose: A passively filling, 45 ml stroke volume MagScrew Total Artificial Heart (TAH) system was tested in-vitro and in-vivo. Focus of the in-vitro experiments was the demonstration of preload and afterload sensitivity, atrial balance and flow capabilities. Goal of the in-vivo studies was the demonstration of blood/biocompatibility of all implanted system components and exercise tolerance on a treadmill. Methods: The in-vitro studies utilized a mock circulation, evaluating device performance in fixed rate and automatic control mode. The in-vivo experiments were conducted in calves. The TAH system was operated in automatic control mode. Results: In-vitro tests showed excellent preload sensitivity resulting in device flows above 10 L/Min at a beat rate of 220 BPM, at a systemic mean afterload of 100 mm Hg and a left atrial pressure of 13 mm Hg. Atrial balance was maintained at all tested conditions. Separate tests demonstrated low afterload sensitivity and a device flow of up to 14 L/min at beat rates of up to 280 BPM. Four in-vivo studies with durations between 4 - 83 days confirmed the in-vitro results with average flows ranging between 8.7 – 10.4 L/min at average beat rates ranging between 204 – 224 BPM. Hemodynamics remained normal with excellent left right atrial balance throughout the course of each experiment. Hemolysis was not detected in any animal. End-organ function was well maintained without thromoembolic events. The exercise tolerance of all animals was good, without signs of anaerobic metabolism.

Simultaneous Optimization of Traveling Control Based on Operator's Command and Automatic Settling Control

In conveyance systems as crane, both a control mode based on operator's command and an automatic control mode are required. Taking the feature of the nonstationary optimal control method (NOCM) into account, this study applies the idea of NOCM to the problem consisting of the traveling control mode following the operator's command and the automatic settling control mode for positioning of a cart with vibration system. The effectiveness of the method is verified experimentally.

振動系のオペレータ指令に基づく搬送制御と自動整定制御の統一的設計(J22-2 センサ・アクチュエータシステムとその知能化(2),J22 センサ・アクチュエータシステムとその知能化-実環境で活躍するメカトロニクスを目指して)

Nonstationary optimal control method (NOCM) is one of the most effective methods for control problems consisting of plural control modes. NOCM realizes a smooth switching of the modes along time passage and enables us to unify the designs for plural modes and produces the optimal controller based on single criterion function including plural control objectives. In conveyance systems as crane, both a control mode based on operator's command and an automatic control mode are required. Taking the feature of NOCM into account, this study applies NOCM to the problem consisting of the traveling control mode following the operator's command and the automatic settling control mode for positioning of a cart with vibration system. The effectiveness of the method is verified theoretically and experimentally.

Local Automatic Control Modes in an Experimental Irrigation Canal

The paper presents twolocal PI automatic control modes developed,tuned and verified in an experimentalautomatic canal. The canal was used as aphysical model and it will support furtherstudies on canal automation domain. Thecontrol algorithms are installed in localPLC's with the objective of controlling thewater depths immediately upstream anddownstream of the corresponding checkgates. The strategy adopted to tune the PIcontrollers was to compare the frequencyresponse of the state space model, whichrelies on the linearized Saint-Venantequations, with a simple model consideringeach canal pool as a reservoir (reservoirmodel). The obtained results for thecontrol gains were validated by fieldtests. A few simulation results are alsopresented as well as the experimentalfacility and the main configuration of theSCADA developed for the canal supervisionand monitoring.

Autopilot and track-keeping algorithms for high-speed craft

A track autopilot predictor (TAP) system for high-speed craft with waterjet propulsion systems has been developed and installed on-board four catamarans. The TAP system includes automatic control modes for steady-state course-keeping, turning and track-keeping. A special harbour mode and a hydrodynamic predictor based on a non-linear manoeuvring model of the ship are also included. The paper describes the design of the control algorithms used in the autopilot and track-keeping systems. The design is based on a combination of velocity scheduling, pole placement and a feed-forward model for turning. The performance of the algorithms is illustrated in full-scale experiments.

Autopilot and Track-Keeping Algorithms for High Speed Craft

A Track Autopilot Predictor (TAP) system for high speed craft with waterjet propulsion systems has been developed and installed onboard four catamarans. The TAP system includes automatic control modes for steady state course keeping, turning and track-keeping. A special harbour mode and a hydrodynamic predictor based on a non-linear manoeuvring model of the ship are also included. The paper describes the design of the control algorithms used in the autopilot and track-keeping systems. The design is based on a combination of velocity scheduling, pole placement and a feedforward model for turning. The performance of the algorithms is illustrated in full-scale experiments.

Development of Coil Transportation System for Wakayama Cold Strip Mill

Abstract A new coil transportation control system has been developed for the cold strip mill at Wakayama steel works, which has reduced the coil transportation work force by 49%. The function of automatic control of coil transfer vehicles has become indispensable in real operations and is used 24 hours a day. The expert system and simulation techniques used in this function have doubled software productivity compared to common programming methods used in its transportation control, and within only two weeks of its startup, this automatic control mode achieved a coil transportation control rate of 98%.

Development of a microcontroller-based automatic control system for the electrohydraulic total artificial heart.

An automatic physiological control system for the actively filled, alternately pumped ventricles of the volumetrically coupled, electrohydraulic total artificial heart (EHTAH) was developed for long-term use. The automatic control system must ensure that the device: 1) maintains a physiological response of cardiac output, 2) compensates for an nonphysiological condition, and 3) is stable, reliable, and operates at a high power efficiency. The developed automatic control system met these requirements both in vitro, in week-long continuous mock circulation tests, and in vivo, in acute open-chested animals (calves). Satisfactory results were also obtained in a series of chronic animal experiments, including 21 days of continuous operation of the fully automatic control mode, and 138 days of operation in a manual mode, in a 159-day calf implant.

Anaerobic threshold in total artificial heart animals.

The anaerobic threshold represents an objective measure of functional capacity and is useful in assessment of pulmonary and cardiovascular dysfunction. This study determined the anaerobic threshold in total artificial heart animals and evaluated the performance of the total artificial heart system. Five animals with total artificial hearts were put under incremental exercise testing after exercise training. The intensity of exercise ranged from 2.0 to 4.5 km/hr, with an increment of 0.5 km/hr every 3 min. The anaerobic threshold was 6.72 +/- 0.84 ml/kg/min as detected by the lactate method, and 6.48 +/- 0.79 by the CO2 method. The value of the anaerobic threshold in total artificial heart animals implies that the performance capacity of a total artificial heart is not sufficient to meet the oxygen requirements of vigorously exercising skeletal muscle. The protocol does not allow for driving parameter changes during exercise, and this situation, combined with the manual mode of the control system used, was inadequate to allow the total artificial heart animals to exercise more vigorously. Using an automatic control mode might be helpful, as well as considering the relationship between indices of oxygen metabolism, such as oxygen delivery, oxygen consumption, and oxygen extraction rate, in the control algorithms in total artificial heart control systems.

Performance advances in ion mobility spectrometry through combination with high speed vapor sampling, preconcentration and separation techniques

Rugged, low weight, hand-held ion mobility spectrometry devices, initially developed for chemical warfare detection purposes, possess attractive characteristics as field-portable instruments for paramilitary (treaty verification, chemical demilitarization, drug interdiction, counterterrorism operations) and civilian (environmental monitoring, forensic characterization, process control) applications. Generally, however, such devices tend to exhibit limited resolution, narrow dynamic range, nonlinear response and long clearance times which severely limit their usefulness for qualitative and quantitative analysis of mixtures. To overcome these restrictions a prototype combined gas chromatography-ion mobility spectrometry (GC-IMS) unit was constructed by replacing the membrane inlet of a military IMS device known as the CAM (chemical agent monitor) with suitable front-end modules. These modules enable high speed automated vapor sampling (AVS), microvolume preconcentration/thermal desorption, and isothermal GC preseparation of analytes using a short capillary column while operating the IMS source and cell at subambient pressures as low as 0.5 atm. The AVS-GC-IMS methodology sharply reduces competitive ionization and facilitates identification of mixture components, thereby enabling quantitation of volatile and semivolatile compounds over a broad range of concentration in air. At higher concentration levels (e.g. > 1 ppm) using the AVS inlet in automatic attenuation control (AAC) mode maintains excellent linear response. At ultralow concentration levels, e.g. < 10 ppb, a microvolume, trap-and-desorb type preconcentration module, maintains adequate signal to noise levels, thereby expanding the effective dynamic range of the method to approx. 6 orders of magnitude (100 ppt-100 ppm). The resulting “hyphenated” GC-IMS technique has the potential of evolving into the first hand-portable, combined chromatography-spectroscopy instruments for field screening applications.

Comparison of beam‐hardening and K‐edge filters for imaging barium and iodine during fluoroscopy

This study investigated the dose reduction performance of several beam-hardening and K-edge filter materials for the imaging of barium or iodine during fluoroscopy. A computer model was developed to simulate the effect of added filtration on entrance exposure rate (Xp), integral dose rate (Di), contrast (C), signal to noise ratio (SNR), imaging performance per dose (SNR2/Di), and tube load. The model incorporated the response characteristics, in both manual and automatic control modes of operation, of fluoroscopic systems to increasing or decreasing x-ray intensity at the input of the image intensifier. Input parameters to the computer model included choice of filter material and thickness, a barium or iodine test object, tube potential, phantom thickness, a CsI input phosphor, and a set of algorithms for controlling the fluoroscopic system. In all cases, the performance of systems with added filtration was judged with respect to a reference system operating under comparable conditions. In general, either beam-hardening or K-edge filters provided a significant reduction in entrance exposure and integral dose rates, but with an attendant increase in tube load. For a fluoroscopic system constrained to follow a representative automatic brightness control algorithm, added filtration provided a reduction in entrance exposure and integral dose rates for all phantom or uniformly distributed barium thickness. However, the imaging performance per dose, in some cases, decreased rapidly and was less than that of the reference system at large thicknesses. Only as change in the algorithm controlling the kVcp and mA operating points on the fluoroscopic system provided an imaging performance per dose greater than the reference system's at large thicknesses. The practical implementation of adding filtration to fluoroscopic systems is most simply accomplished with beam-hardening filters rather than K-edge filters. However, the systems with K-edge added filtration can provide slightly better performance when used over a limited range of phantom thicknesses such as the range normally associated with pediatric patients.

In Vivo Long-Term Evaluation of the Utah Electrohydraulic Total Artificial Heart

An electrohydraulic total artificial heart (EHTAH) has been developed and evaluated by long-term in vivo studies. The EHTAH is composed of blood pumps with an interatrial shunt (IAS), an energy converter, and electronics. The EHTAH with external electronics was implanted in four calves weighing from 81-90 kg. Two animals died on the 1st and 5th post operative days, the third animal survived for 32 days, and the fourth for 159 days. The IAS was free of thrombus at autopsy in all animals. The longest surviving animal increased in size from a pre operative weight of 81 kg to 134 kg on day 144. Cardiac output ranged from 9.3 to 10.5 L/min, whereas right and left atrial pressures increased with the calf's growth from 4-10 to 16-20 mmHg and from 8-14 to 18-22 mmHg, respectively. The animal favorably tolerated up to 3.4 km/hr of treadmill exercise, both hemodynamically and metabolically. The elevation of atrial pressures during treadmill exercise was significantly alleviated by employing an automatic control mode. It is concluded that the device has the potential to be a totally implantable system for permanent use.

Dual Mode Control Method of Micro-Manipulator with Visual Feedback

This paper deals with the dual mode control method of a micro-manipulator system, consisting of the teleoperation control mode and the automatic control mode. The teleoperation control mode is based on the bilateral master-slave type of a micro-manipulator operated by humans, which requires the contractive position and force control. Refering the conventional methods, a new tele-operation method is proposed as the impedance type of the manipulation. Some experimental comparison with the conventional methods is carried out. Then the automatic control mode is shown based on fully automatic visual feedback control, modifying the teleoperation control mode with visual feedback control. In this mode, the tracking and capturing control of moving objects is also possible with the adaptive force control taking account of object dynamics. The teleoperation mode can be used as the teaching mode, then the automatic control mode can be used for successive operations.

AlGaAs/GaAs self-aligned LD's fabricated by the process containing vapor phase etching and subsequent MOVPE regrowth

A new fabrication process has been successfully applied for the first time to the AlGaAs/GaAs laser diode. This new process includes vapor phase etching and subsequent MOVPE regrowth. Self-aligned LD's fabricated by this process have shown sufficiently good characteristics ( Ith = 50-60 mA, \eta_{D} = 40-45 percent), and good reliability (no degradation at least up to 1000 h:50°C, 5mW, automatic power control mode).

High-power high-reliability operation of 1.3 µm p-substrate buried crescent laser diodes

Stable high-power CW operation of 1.3-μm InGaAsP/InP p-substrate buried crescent laser diodes (PBC-LD'S) has been realized, by controlling the front and rear facet reflectivities of the laser diode chips. The front facet reflectivity is reduced to 17 percent and the rear facet reflectivity is increased to 90 percent, by evaporating multilayer dielectric films (Si/Al 2 O 3 SiO 2 :17 percent, SiO 2 /Si/SiO 2 /Si/SiO 2 :90 percent) on each facet. CW light output power of 50 mW is achieved up to 60°C. Aging tests have been carried out under automatic power control (APC) mode conditions of 50°C-30 mW, 40 mW, 50 mW, and 30°C-50 mW. All samples are operating stably in spite of junction-up configuration. The lifetimes are estimated to be more than 2 \times 10^{4} h for all conditions.

The efficient evaluation of soil trafficability of planetary vehicles

The authors discuss problems of ensuring safe motion of vehicles moving on the planetary surface in remote and automatic control modes when the interaction of the driver and soil should be constantly assessed and the possibility of further motion forecast. The authors substantiate for these purposes the use of methods of analyzing the interaction of the driver and soil directly in the process of motion. They suggest criteria of assessing this interaction and methods of solving problems of motion control and safety of vehicles' operation. Methods of analyzing the soil trafficability of Lunokhods 1 and 2 are presented. The recommended mathematical expressions of the suggested criteria ensure a sufficient simplicity of information controlling devices.

Automatic Control of the Skylab Astronaut Maneuvering Research Vehicle

The two automatic control modes of the Astronaut Maneuvering Research Vehicle (AMRV) are analyzed: the Control Moment Gyro (CMG) and the Rate Gyro (RG). The AMRV is an autonomous maneuvering unit which translates and rotates the pilot by means of hand-controll er input commands. The CMG normal operation, desaturation, and cage/lock dynamics are described in terms of a typical AMRV mass property configuration. No propellant is used for normal operation in the CMG mode, and the maximum rotation rate is 5°/sec about each AMRV axis. The.RG attitude maneuvering and limit cycle submode dynamics are described in terms of the same AMRV mass property configuration. In the RG mode, attitude and attitude rate are maintained within limits of ±4° and ±2°/sec, respectively; the maximum rotation rate is 20°/sec about each AMRV axis. Translational maneuvering is identical in either mode, with linear velocities normally not exceeding 0.5 fps.

Effectiveness of the harmonic-balance method in the investigation of stationary automatic phase frequency control modes

Effectiveness of the harmonic-balance method in the investigation of stationary automatic phase frequency control modes