DESIGN AND IMPLEMENTATION OF AN OBJECT TRACKING SYSTEM CONTROL USING PID AND MOVEMENT PREDICTION

The tracking system usually has some lack of problem, that is unstable system when the object moved so the tracking process can’t define the object position well. On the other hands, when the object moves, the system can’t track object suddenly along to the direction of objects movement. The system will always looking for the object from the first point or its home position. In this paper, PID control was used to improve the stability of tracking system, so that the result became more stable than before, it can be seen from errorof tracking. Otherwise, to looking for again the undetected object, a linier regression method was used in purpose to get more faster in finding the new position of a movement object that was disappear from the views of camera before . When the object on unmoved condition, the system has error value ±15 pixel. For horizontal move condition of servo on slow motion ±9.4 pixel, also on the fast motion, the error values is about ±20.1 pixel. For the servo with vertical movement ,the error value is about ±13.4 pixel for the slow motion and ±45.7 pixel for fast motion. The process on finding the object that was disappear from the views of camera before, ±2 second. Finally it can be concluded that the add of PID control and linear regression method, make the tracking system become more stabile and real time. Keyword : tracking object, PID control, regression method, real time system

Laser system detects tower deflections

Continuously measure and record deflection of facility during testing. Facility deflections are then subtracted from shroud deflections during data reduction on computer. System is based on tracking light beam by using two-axis photo detector and feeding signals into X and Y servo system

Development of smart solar tracking system

The project is to design an active solar tracking system which able to track the sunlight with the aid of light dependent resistor (LDR) as input sensor to read the intensity of sunlight. The solar tracking system uses platform as a base and it is moved by a servo motor as the platform needs to be moved towards the sunlight to get the optimum light. The solar tracking system is programmed by using microcontroller Arduino Uno as a main controller. After the setup of the hardware and program, the tracking motion of the tracking system has been implemented to track the sun based on sunlight direction. In this work, it is designed that the motion of the tracking system is depends on the value read by LDR. As a conclusion, the solar tracking system can increase the solar panels efficiency by keeping the solar panels perpendicular with sun’s position

High-performance control of dual-inertia servo-drive systems using low-cost integrated SAW torque transducers

Abstract—This paper provides a systematic comparative study of compensation schemes for the coordinated motion control of two-inertia mechanical systems. Specifically, classical proportional–integral (PI), proportional–integral–derivative (PID), and resonance ratio control (RRC) are considered, with an enhanced structure based on RRC, termed RRC+, being proposed. Motor-side and load-side dynamics for each control structure are identified, with the “integral of time multiplied by absolute error” performance index being employed as a benchmark metric. PID and RRC control schemes are shown to be identical from a closed-loop perspective, albeit employing different feedback sensing mechanisms. A qualitative study of the practical effects of employing each methodology shows that RRC-type structures provide preferred solutions if low-cost high-performance torque transducers can be employed, for instance, those based on surface acoustic wave tecnologies. Moreover, the extra degree of freedom afforded by both PID and RRC, as compared with the basic PI, is shown to be sufficient to simultaneously induce optimal closed-loop performance and independent selection of virtual inertia ratio. Furthermore, the proposed RRC+ scheme is subsequently shown to additionally facilitate independent assignment of closed-loop bandwidth. Summary attributes of the investigation are validated by both simulation studies and by realization of the methodologies for control of a custom-designed two-inertia system

Visual servoing with nonlinear observer

Visual servo system is a robot control system which incorporates the vision sensor in the feedback loop. Since the robot controller is also in the visual servo loop, compensation of the robot dynamics is important for high speed tasks. Moreover estimation of the object motion is necessary for real time tracking because the visual information includes considerable delay. This paper proposes a nonlinear model-based controller and a nonlinear observer for visual servoing. The observer estimates the object motion and the nonlinear controller makes the closed loop system asymptotically stable based on the estimated object motion. The effectiveness of the observer-based controller is verified by simulations and experiments on a two link planar direct drive robot</p

Dial It In: Rotating RF Sensors to Enhance Radio Tomography

A radio tomographic imaging (RTI) system uses the received signal strength (RSS) measured by RF sensors in a static wireless network to localize people in the deployment area, without having them to carry or wear an electronic device. This paper addresses the fact that small-scale changes in the position and orientation of the antenna of each RF sensor can dramatically affect imaging and localization performance of an RTI system. However, the best placement for a sensor is unknown at the time of deployment. Improving performance in a deployed RTI system requires the deployer to iteratively "guess-and-retest", i.e., pick a sensor to move and then re-run a calibration experiment to determine if the localization performance had improved or degraded. We present an RTI system of servo-nodes, RF sensors equipped with servo motors which autonomously "dial it in", i.e., change position and orientation to optimize the RSS on links of the network. By doing so, the localization accuracy of the RTI system is quickly improved, without requiring any calibration experiment from the deployer. Experiments conducted in three indoor environments demonstrate that the servo-nodes system reduces localization error on average by 32% compared to a standard RTI system composed of static RF sensors.Comment: 9 page

SAW torque transducers for disturbance rejection and tracking control of multi-inertia servo-drive systems

The paper proposes a resonance ratio control (RRC) technique for the coordinated motion control of multi-inertia mechanical systems, based on the measurement of shaft torque via a SAW-based torque sensor. Furthermore, a new controller structure, RRC plus disturbance feedback is proposed, which enables the controller to be designed to independently satisfy tracking and regulation performance. A tuning method for the RRC structure is given based on the ITAE index, normalized as a function of the mechanical parameters enabling a direct performance comparison between a basic proportional and integral (PI) controller. The use of a reduced-order state observer is presented to provide a dynamic estimate of the load-side disturbance torque for a multi-inertia mechanical system, with an appraisal of the composite closed-loop dynamics. It is shown that the integrated formulation of the tuning criteria enables lower bandwidth observers to be implemented with a corresponding reduction in noise and computational load. The control structures are experimentally validated via a purpose designed test facility and demonstrate significant improvement in dynamic tracking performance, whilst additionally rejecting periodic load side disturbances, a feature previously unrealisable except by other, high-gain control schemes that impose small stability margins

The Palomar Testbed Interferometer

The Palomar Testbed Interferometer (PTI) is a long-baseline infrared interferometer located at Palomar Observatory, California. It was built as a testbed for interferometric techniques applicable to the Keck Interferometer. First fringes were obtained in July 1995. PTI implements a dual-star architecture, tracking two stars simultaneously for phase referencing and narrow-angle astrometry. The three fixed 40-cm apertures can be combined pair-wise to provide baselines to 110 m. The interferometer actively tracks the white-light fringe using an array detector at 2.2 um and active delay lines with a range of +/- 38 m. Laser metrology of the delay lines allows for servo control, and laser metrology of the complete optical path enables narrow-angle astrometric measurements. The instrument is highly automated, using a multiprocessing computer system for instrument control and sequencing.Comment: ApJ in Press (Jan 99) Fig 1 available from http://huey.jpl.nasa.gov/~bode/ptiPicture.html, revised duging copy edi