hardware in the loop

In this work, robust adaptive control of a 3_Axis Motion Simulator robot for Hardware-in-the-Loop testing of sensor units with specified dimensions and mass are investigated. Initially, 3_Axis Motion Simulator robot is introduced, followed by extracting electromechanical equations governing the system using the iterative NewtonEuler method. Subsequently, considering the electromechanical model and taking uncertainties into account, a fuzzy sliding mode controller is designed for motion simulator, and after simulation, it is implemented on the system. The implementation results demonstrate the controller's satisfactory performance in tracking desired commands in the presence of uncertainties. Also, the results show that adding a fuzzy system to determine the saturation limits of actuators reduces the chattering caused by the sliding mode control structure.

This article examines the design and construction of a hardware-based two-axis angle control mechanical device in the loop in order to build a two-axis test bed. This device aims to reach the test bed of two-axis angle control with a small error in order to evaluate and test position sensors or as a small two-degree-of-freedom table to control the position of satellite components. The device consists of two main parts, a mechanical structure and an electronic part, and the control algorithm is written in the hardware platform in the ring, and there is the ability to define all kinds of controllers on it. The structure consists of a rotatable rod, coupling, bearings, body, base and electronic part of a processor board, encoder sensor, battery, telecommunication module and a coreless motor with a rotating disk as a reaction wheel. This device has the ability of pitch and yaw maneuvers as two degrees of freedom, and its position error is proportional to the control algorithm. The reliability of the accuracy of this device per hundred repetitions of the test for the mentioned maneuvers is 0.11 and 0.2 degrees, respectively, with the PID controller. The performance analysis of the device has been investigated in detail by examining different input angles, various controller coefficients, different initial conditions, single-axis and two-axis maneuvers. The obtained results indicate the proper performance of the device with an average error of less than 0.23 degrees.

One of the current problems in the development of simulation software of flying objects is the process of software development and development from the concept design phase of a project to the final stages of the hardware in the loop. In this paper, the necessary software engineering standards and procedures for the production of rigid multi-stage launch vehicle simulation software with a new approach are introduced in order to overcome this problem. The proposed RUP structure for the production of software with six degrees of freedom simulation software's ability to be used quickly and with minimal modifications in loop software and loop hardware labs.

The main purpose of this paper is presentation a novel approach of inertial-vision based navigation to increase accuracy and safety factor simultaneously. In order to estimate navigation parameters, consist of velocity, position and orientation (attitude) the Extended Kalman Filter (EKF) is used. In proposed method, the Inertial Measurment Unit (includes of 3-axis accelerometer and gyrospope) and vision data considered as navigation process model and measurement model respectively. By utilizing the Scale Invariant Feature Transform (SIFT) method, means transform the image data in to scale invariant coordinates relative to local feature, the 2D position of UAV is obtained. The real time Hardware in the Loop (HIL) simulation technique is used To evaluate overall system performance and efficiency such as serial interface time delay, appropriate operating frequency selection and micro-controller performance at implemented image processing and data fusion algorithm. The real time HIL simulation results clearly show despite of low frequency in vison based navigation, proposed approach has acceptable accuracy for estimating uav navigation paraqmeters. Maintaining accuracy and cost, the proposed approach can be a suitable alternative method to drones that use GPS-based navigation.

In this paper, design and implementation of model predictive controller for turbofan engine fuel control are proposed. The satisfaction of operational and structural limits of the engine is a controller design challenge. The control system must ensure that the engine operates without any limit violation at all times, i.e. without over-speed of the shaft, compressor stall, combustion chamber blow out and turbine over-temperature. In this regard, a controller is required which can take into account these constraints while obtaining an optimal control input. Therefore, the model predictive control for turbofan engine fuel control using a linear model of the engine at one operating point is designed. The simulation results show that while model predictive control generate optimal control signal, all the constraints are perfectly satisfied. After assuring the valid performance of the controller in computer simulations, the fuel control algorithm is implemented on a hardware framework. For this purpose, the controller algorithm is implemented on a microcontroller and hardware-in-the-loop test is performed. The results of the hardware-in-the-loop simulation indicate the correct implementation of the model predictive controller on the hardware framework.

This paper presents a new method to design stabilizing and tracking control laws for a class of nonlinear systems whose state space description is in the form of polynomial functions. This method employs the nonlinear model directly in the controller design process without the need for local about an operating point. The approach is based on the sum of squares (SOS) decomposition of multivariate polynomials which is transformed into a convex optimization problem. It is shown that the design problem can be formulated as a sum of squares optimization problem. This method can guarantee of the nonlinear system with less conservatism than based Also, a sum of squares technique is used to evaluate the stability of closed loop system state with respect to exogenous input. The nonlinear dynamic model of air vehicles can usually be expressed by polynomial nonlinear equations. Therefore, the proposed method can be applied to design an air vehicle autopilot. The hardware in the loop (HIL) simulation is an important test for evaluation of the aerospace control system before flight test. The HIL results using designed controller for a supersonic air vehicle are presented. The results from HIL is compared to the software simulation that the appropriate consistency of results shows the efficiency of the proposed method in the air vehicle autopilot control loop.

In this paper, the performance of two robust control algorithms, µ-synthesis and high order sliding mode are evaluated on a spacecraft attitude control subsystem simulator as the hardware in the loop. This tabular simulator is placed on a spherical air bearing to validate real-time environment. All actuators and sensors on the platform of spacecraft simulator prepare real conditions as attitude control test bed. Beginning, both designed controllers are simulated by Matlab software, next they are applied on the subsystem. At first, µ-synthesis robust controller is designed for simulator. In this method, weighting matrix are chosen such that the controller becomes robust in combined uncertain condition such as system uncertainties, environmental disturbances and sensor noises. Uncertainty, performance, actuator saturation, disturbance and noise weighting functions are designed based on the dynamics and environmental platform properties. At least high order sliding mode controller based on super twisting algorithm is designed to reduce chattering effects. Contrary to the other second order sliding mode algorithms, in the super twisting method sliding surface derivatives are not used. The Computer and experimental hard ware in the loop simulations are compared together.

Recently, robotic systems are widely used in surgery, due to their characteristics such as having high precision, being tireless and making no mistakes. They are especially suitable for operation on hard tissue, as the bone is stationary and does not change shape and therefore preoperative planning of the system is much more straightforward. Nevertheless, proposed robotic systems for surgery on skull bone are still in the research stage. In this study, by considering the requirements of craniotomy surgery, a Remote Center of Motion spherical mechanism is used in design and prototyping of a surgical system. The kinematic equations and Jacobian of the mechanism are calculated analytically and later verified through software simulation. Detailed design and force analysis helped selection and use of appropriate AC servo motors for actuation. An aluminum prototype is fabricated out of CNC machined parts. Performance of different connection methods between PC and the robot were tested and a combination of them is proposed for higher reliability and speed. Finally, a software library is generated in LabVIEW environment to simplify the connection with servo motors and utilization and control of the robotic system.

In this paper, achieving of Stereo-Imaging scenario by a remote sensing satellite will be presented. Then a suitable attitude control system will be designed using 4 reaction wheels with pyramidal structure to fulfill large angle maneuvers of stereo-imaging scenario. The proposed attitude control system provide the satellite with the capability of nadir pointing and large angle maneuvers to take different images of a predefined zone from different point of view. In order to verify the performance of the designed attitude control system, a low-cost real time hardware in the loop test bed will be constructed. The constructed test bed is capable of assessing attitude control algorithms in a real time conditions. In the proposed test bed, accurate and real time modeling of satellite dynamics, space conditions, reaction wheels and gyroscopes will be done by the Simulator computer. Finally, performance of the designed attitude controller to achieve stereo-imaging scenario is investigated by implementing the algorithm in the hardware in the loop test bed in a real time condition.