Position Control Experiments Research Articles

The Electronic Throttle PID Control System Based on Single Chip Microcomputer

With Bosch company DV - E5 type throttle as control object，the hardware and software of the control system has been designed based on PID control algorithm. System uses TT89C51 microcontroller as the main control unit, using LMD18200 chip to drive DC motor in the throttle, at the same time, using PCF8591 as the AD conversion chip, using LCD1602 to display the dynamic control parameters. The system control software has been written by C language, The main software modules have been simulated on Proteus, an PID control experimental platform of the electronic throttle has been built, Test and the experiments of the opening degree position control on the throttle have been completed, the experimental results show that the system step response time is about 300ms, the steady-state error is less than 1%, hysteresis and overshoot is not obvious.

Feedback Controller With Low-Pass-Filter-Based Delay Regulation for Networked Control Systems

This paper proposes a novel traffic shaping algorithm for jitter buffers. Jitter buffers are effective in reducing jitter and therefore constitute an important technique used to improve the quality of real-time communication. Traffic shaping regulates the interval between packets received at the destination. Although the well-known dynamic jitter buffer needs to identify the maximum one-way delay and current one-way delays in the network, it is not necessary for our proposed approach to supply this information. Our algorithm utilizes a feedback controller to adjust the queuing delay in the jitter buffer to avoid packet overrun and underrun. In addition, a constant packet-receiving interval is achieved by employing a low-pass filter. The validity of our proposed method is confirmed through experiments of position control over a network.

3A1-B02 単孔式腹腔鏡下手術(SPS)支援用ロボットの位置制御(医療ロボティクス・メカトロニクス(1))

This paper presents a position control strategy of a surgical robot for Single Port Surgery (SPS). The kinematics of the surgical robot is analyzed and a position control method on the basis of inverse kinematics is proposed to control the surgical robot intuitively. First, the forward kinematics of the surgical robot for SPS is derived using 6 coordinate transformations. Secondly, Jacobian matrix is obtained through the derived forward kinematics. Finally, a numerical solution of the inverse kinematics problem is derived by using the Jacobian matrix and Newton's method. Experiments of position control were carried out, and experimental results are presented.

Three-Axis Disturbance-Free Attitude Control Experiment Platform : FACE

The Facility for Attitude Control Experiments (FACE) has been implemented at the Institute of Space Systems of German Aerospace Center (DLR) in Bremen, Germany. The facility’s objective is testing and verification of the Attitude Determination and Control System (ADCS) under the realistic environment in low Earth orbit. Regarding the evolving ADCS software and hardware, a complete end-to-end verification of ADCS significantly contributes to the mission success. FACE consists of a hemispherical air-bearing with satellite component platform, preliminary solar simulator, and magnetic field simulator. Besides, the implemented automatic center of mass (CoM) calibration software adjusts the CoM of the whole platform and, thus, it can perform minimal friction motions in 3 axes as if in orbit. Furthermore, the platform provides multi-output power distribution system and WLAN command interface. Thus a self-sustaining satellite is arranged on the platform which can be subjected to various tests. A hardware-in-the-loop test using flight components can be performed simply by mounting the desired sensor or actuator onto the platform. In particular, FACE is now prepared for the system verification of DLR’s CompactSatellite program. We introduce the real-time test bench with specific devices, their performances, and future extensions in progress.

ON-ORBIT ATTITUDE CONTROL EXPERIMENTS FOR ETS-VI BY I-PD CONTROL

ON-ORBIT ATTITUDE CONTROL EXPERIMENTS FOR ETS-VI BY I-PD CONTROL

안전성을 고려한 모델 기반 제어기 설계

Model based design method reduces product development period and increases system software safety. In this paper, a BLDC motor controller based on model based design method is designed with Simulink and implemented with auto generated code which is written in C language. To retain the safety of software, this model is implemented according to MISRA AC SLSF guide. The validity of the implemented controller is verified with a real position control experiment, and execution times of each control loops are measured to compare the system performance of the conventional design and the model based design.

ATTITUDE CONTROL OF SMALL UNMANNED FOUR-ROTOR HELICOPTER BASED ON ADAPTIVE INVERSE CONTROL THEORY

A dynamic model of small unmanned four-rotor built according to Newton-Euler formalism was proposed in this paper. Base on this model, Adaptive Inverse Control (AIC) Theory was used in the control of the small unmanned four-rotor for the first time and the attitude stabilization control was also realized on the experimental platform. The attitude control experiment indicates that AIC is robust in the attitude control of the small unmanned four-rotor. DOI: http://dx.doi.org/10.5755/j01.mech.18.1.1288

Design and Attitude Control of a Quad-Rotor Tail-Sitter Vertical Takeoff and Landing Unmanned Aerial Vehicle

In this paper, we present the development of a quad-rotor tail-sitter unmanned aerial vehicle (UAV) that is composed of quad rotors and a fixed wing. The developed UAV can hover like a quad-rotor helicopter and can fly long distance like a fixed-wing airplane. The main wing of the developed UAV is taken from a commercially available radio-controlled airplane and other parts such as the body frame are newly developed. A microcomputer, various sensors and a battery are mounted on the UAV for autonomous flight without any support from a ground system. Attitude and altitude control systems are developed for the UAV. In order to verify the designed controller, a three-dimensional flight simulator of a quad-rotor tail-sitter UAV is developed by use of MATLAB/Simulink. This paper also describes attitude control experiments. The results show that the propeller slipstream has a negative influence on attitude control. Solutions for the negative influence of the propeller slipstream are also discussed in this paper.

On-orbit verification of fuel-free attitude control system for spinning solar sail utilizing solar radiation pressure

This paper introduces a new attitude control system for a solar sail, which leverages solar radiation pressure. This novel system achieves completely fuel-free and oscillation-free attitude control of a flexible spinning solar sail. This system consists of thin-film-type devices that electrically control their optical parameters such as reflectivity to generate an imbalance in the solar radiation pressure applied to the edge of the sail. By using these devices, minute and continuous control torque can be applied to the sail to realize very stable and fuel-free attitude control of the large and flexible membrane. The control system was implemented as an optional attitude control system for small solar power sail demonstrator named IKAROS (Interplanetary Kite-craft Accelerated by Radiation Of the Sun). In-orbit attitude control experiments were conducted, and the performance of the controller was successfully verified in comparison with the ground-based analytical performance estimation.

Using Artificial Neural Networks for Energy Regulation Based Variable-speed Electrohydraulic Drive

In the energy regulation based varibable-speed electrohydraulic drive system, the supply energy and the demanded energy, which will affect the control performance greatly, are crucial. However, they are hard to be obtained via conventional methods for some reasons. This paper tries to a new route: the definitive numerical values of the supply energy and the demanded energy are not required, except for their relationship which is called energy state. A three-layer back propagation(BP) neural network was built up to act as an energy analysis unit to deduce the energy state. The neural network has three inputs: the reference displacement, the actual displacement of cylinder rod and the system flowrate supply. The output of the neural network is energy state. A Chebyshev type II filter was designed to calculate the cylinder speed for the estimation of system flowrate supply. The training and testing samples of neural network were collected by the system accurate simulation model. After off-line training, the neural network was tested by the testing data. And the testing result demonstrates that the designed neural network was successful. Then, the neural network acts as the energy analysis unit in real-time experiments of cylinder position control, where it works efficiently under square-wave and sine-wave reference displacement. The experimental results validate its feasibility and adaptability. Only a position sensor and some pressure sensors, which are cheap and have quick dynamic response, are necessary for the system control. And the neural network plays the role of identifying the energy state.

Orbital Experiments of Linearly Interpolated Gain Scheduling Attitude Controller Using ETS-VIII Spacecraft

AbstractThis paper describes orbital attitude control experiments carried out on the ETS (Engineering Test Satellite)-VIII in June 2009. These experiments aim to develop a technical basis for the orbital control of a class of future large flexible spacecraft. Several novel robust control laws were tested, including a μ-synthesis based control law, a DVDFB (Direct Velocity and Displacement FeedBack) control law and a linearly interpolated gain scheduling law. Among them, this paper focuses on the gain scheduling law. Experimental results of this control law are presented to show its high control performance and lower computational burden compared with other control laws.

Design of Tokyo Tech nano-satellite Cute-1.7+APD II and its operation

Cute-1.7+APD II is the 3rd satellite developed by the Laboratory for Space Systems at the Tokyo Institute of Technology. Cute-1.7+APD II is the current successor to Cute-1.7+APD. This new satellite is based on its predecessor but has some modifications to increase its reliability and robustness against radiation effects, electrical power shortage and so on. The satellite was launched by an ISRO PSLV-C9 rocket on April 28, 2008 and has operated for more than 9 months. Throughout its operation, many missions such as attitude determination and control experiments, scientific observations, photographing and communication experiments have been conducted. In this paper an overview of the Cute-1.7 series and configurations, modifications and operation results of Cute-1.7+APD II are introduced.

Development of 3-DOF Soft Manipulator with ER Fluid Clutches

With robots and users more commonly sharing space such as in the fields of medicine and home automation, the possibility of a physical collision has increased, even though many robots use actuators with high-ratio gear trains to minimize the effects of impact. We developed a 3-DOF manipulator having a smart flexible joint using an ER fluid and a sensor-equipped pneumatic cushion. Results of position control and collision experiments using the manipulator demonstrated its effectiveness.

Design and implementation of robust symmetric attitude controller for ETS-VIII spacecraft

To meet increasing mission requirements, communication satellites are being equipped with large flexible antenna reflectors and solar paddles. A typical such satellite, the Engineering Test Satellite VIII (ETS-VIII) spacecraft, was launched into geostationary orbit by the Japan Aerospace Exploration Agency (JAXA) in December 2006. The main mission of ETS-VIII is to support next-generation mobile digital communications, and for this purpose it is equipped with two large deployable antenna reflectors and a pair of large solar paddles that rotate around the pitch axis. The authors are planning to perform on-orbit attitude control experiments using ETS-VIII at the end of its mission life, aiming to develop a baseline for future controller design for this class of satellite using advanced control theories. This paper proposes two degrees-of-freedom control based on robust direct velocity and displacement feedback as a candidate controller technology. The spacecraft modeling and controller synthesis methods are discussed, and a controller implementation for an on-orbit control experiment is presented with simulation results.

Improving dynamic performances of PWM-driven servo-pneumatic systems via a novel pneumatic circuit

In this paper, the effect of pneumatic circuit design on the input–output behavior of PWM-driven servo-pneumatic systems is investigated and their control performances are improved using linear controllers instead of complex and costly nonlinear ones. Generally, servo-pneumatic systems are well known for their nonlinear behavior. However, PWM-driven servo-pneumatic systems have the advantage of flexibility in the design of pneumatic circuits which affects the input–output linearity of the whole system. A simple pneumatic circuit with only one fast switching valve is designed which leads to a quasi-linear input–output relation. The quasi-linear behavior of the proposed circuit is verified both experimentally and by simulations. Closed loop position control experiments are then carried out using linear P- and PD-controllers. Since the output position is noisy and cannot be directly differentiated, a Kalman filter is designed to estimate the velocity of the cylinder. Highly improved tracking performances are obtained using these linear controllers, compared to previous works with nonlinear controllers.

Use of Pitch and Heave Motion Cues in a Pitch Control Task

During pitch rotation of the aircraft, a pilot, seated in front of the aircraft center of gravity, is subjected to rotational pitch and vertical heave motion. The heave motion is a combination of the vertical motion of the aircraft center of gravity and the heave motion as a result of the pitch rotation. In a pitch tracking task, all of these cues could potentially have a positive effect on performance and control behavior, as they are all related to the aircraft pitch attitude. To improve the tuning of flight simulator motion filters, a better understanding of how these motion components are used by the pilot is required. First, the optimal use of the different motion components was evaluated using an optimal control analysis. Next, an aircraft pitch attitude control experiment was performed in the SIMONA Research Simulator, investigating the effects of pitch rotation, pitch heave, and center of gravity heave on pilot control behavior. Pilot performance significantly improved with pitch motion, with an increased crossover frequency for the disturbance open loop. The increase in performance was a result of an increased visual gain and a reduction in visual lead, allowed for by the addition of pitch motion. Pitch heave motion showed similar but smaller effects. The center of gravity heave motion, although taking up most of the simulator motion space, was found to have no significant effects on performance and control behavior.

Development of 3 DOF manipulator using ER fluid clutches for reduction of collision force

.With robots and users more commonly sharing space such as in the fields of medicine and home automation, the possibility of a physical collision has increased, even though many robots use actuators with high-ratio gear trains to minimize the effects of impact. We developed a 3-DOF manipulator having a smart flexible joint using an ER fluid and a sensor-equipped pneumatic cushion. Results of position control and collision experiments using the manipulator demonstrated its effectiveness.

Development of a Small-spin-axis Controller and Its Application to a Solar Sail Subpayload Satellite

The instruments and actuators in the attitude control system of small spacecraft are restricted in weight and space, and need to be reduced in weight and size. The rhumb line control strategy is one of the most popular schemes in reorientation of spin-stabilized spacecraft, since it requires only a spin sun sensor and a single axis reaction control system. By being combined with active nutation control, rhumb line control can reorient the spin axis of the spacecraft to any direction. To verify the control strategy, we manufactured an attitude controller and demonstration experiments were conducted using a motion table at ISAS/JAXA. This paper reviews the configuration of the controller and the outlines of the experiments, and evaluates the control performance. The same type of controller was installed in the Solar Sail Subpayload Satellite (SSSAT) launched in September 2006. An attitude control experiment in orbit was not conducted because of trouble with the satellite, but new control logic for the SSSAT was implemented for the attitude controller. This paper also reviews the control logic of the SSSAT.

Trajectory Planning of Knife Position of Slitter Robot Based on Identification of Friction and Viscous Damping, and Position Control Experiments

In this study, the trajectory planning method of the knife position of a slitter robot is proposed, and the experimental and numerical simulation results are demonstrated. The slitter robot consists of upper and lower knife driving mechanisms, and a knife driving mechanism was constructed with a worm gear, a ball screw and an alternating current (AC) motor. In the trajectory planning, first, the identification algorithm of the friction and the viscous damping is derived by using the equation of motion of the knife drive mechanism and the experimental results of the dynamic response with constant AC motor torque. Then, the trajectory planning algorithm of the knife position is presented, and a knife position control system is constructed. Furthermore, the experiments and numerical calculations have been carried out, and the usefulness of the present trajectory planning method is confirmed.

Experimental Studies of Real- Time Decentralized Neural Network Control for an X-Y Table Robot

In this paper, experimental studies of a neural network (NN) control technique for non-model based position control of the x-y table robot are presented. Decentralized neural networks are used to control each axis of the x-y table robot separately. For an each neural network compensator, an inverse control technique is used. The neural network control technique called the reference compensation technique (RCT) is conceptually different from the existing neural controllers in that the NN controller compensates for uncertainties in the dynamical system by modifying desired trajectories. The back-propagation learning algorithm is developed in a real time DSP board for on-line learning. Practical real time position control experiments are conducted on the x-y table robot. Experimental results of using neural networks show more excellent position tracking than that of when PD controllers are used only.