Pan-tilt Mechanism Research Articles

High-Magnification Object Tracking with Ultra-Fast View Adjustment and Continuous Autofocus Based on Dynamic-Range Focal Sweep.

Active vision systems (AVSs) have been widely used to obtain high-resolution images of objects of interest. However, tracking small objects in high-magnification scenes is challenging due to shallow depth of field (DoF) and narrow field of view (FoV). To address this, we introduce a novel high-speed AVS with a continuous autofocus (C-AF) approach based on dynamic-range focal sweep and a high-frame-rate (HFR) frame-by-frame tracking pipeline. Our AVS leverages an ultra-fast pan-tilt mechanism based on a Galvano mirror, enabling high-frequency view direction adjustment. Specifically, the proposed C-AF approach uses a 500 fps high-speed camera and a focus-tunable liquid lens operating at a sine wave, providing a 50 Hz focal sweep around the object's optimal focus. During each focal sweep, 10 images with varying focuses are captured, and the one with the highest focus value is selected, resulting in a stable output of well-focused images at 50 fps. Simultaneously, the object's depth is measured using the depth-from-focus (DFF) technique, allowing dynamic adjustment of the focal sweep range. Importantly, because the remaining images are only slightly less focused, all 500 fps images can be utilized for object tracking. The proposed tracking pipeline combines deep-learning-based object detection, K-means color clustering, and HFR tracking based on color filtering, achieving 500 fps frame-by-frame tracking. Experimental results demonstrate the effectiveness of the proposed C-AF approach and the advanced capabilities of the high-speed AVS for magnified object tracking.

Isolating switch state detection system based on depth information guidance

<abstract> <p>This study addressed the critical role of isolating switches in controlling circuit connections for the stable operation of the substation. Our research introduced an innovative state detection system that utilized depth information guidance, comprising a controllable pan-tilt mechanism, a depth camera, and an industrial computer. The software component employed a two-stage strategy for precise isolating switch detection. Initially, the red green blue with depth (RGB-D) saliency network identified the approximate area of the isolating switch target. Subsequently, a fully connected conditional random field was applied to extract accurate detection results. The real-time state of the isolating switch was determined based on the geometric relationship between its arms. This approach enhanced the accuracy of isolating switch detection, ensuring practical applicability in engineering scenarios. The significance of this research lies in its contribution to advancing isolating switch monitoring through depth information guidance, promoting a more robust and reliable power system. The key improvement is implementing a two-stage strategy, combining RGB-D saliency analysis and conditional random field processing, resulting in enhanced accuracy in isolating switch detection. As validated through extensive experiments, the proposed system's successful application in practical engineering underscores its effectiveness in meeting the accuracy requirements for isolating switch detection and state detection. This innovation holds promise for broader applications in power systems, showcasing its potential to elevate the reliability and efficiency of electrical networks. Code of the proposed system is available at: <ext-link ext-link-type="uri" xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="https://github.com/miaomiao0909/Isolating-Switch-Detection/tree/master">https://github.com/miaomiao0909/Isolating-Switch-Detection/tree/master</ext-link>.</p> </abstract>

Localizing an underwater sensor node using sonar and establishing underwater wireless optical communication for data transfer applications

Locating an underwater sensor node over the seabed and acquiring fast, secure data communication between the node and an underwater vehicle could lead to advancements in underwater exploration and marine technology. Currently, the seabed is extensively mapped using multibeam sonar modules, providing detailed information about the bed. Because of its high computational requirements and cost, multibeam sonar is not suitable for this application. The aim of this article is to deploy an experimental setup with a single-beam sonar to localize the node, and then, establish a communication link. The single beam sonar has a 30° beamwidth, which can be improvised to have a full range scan using a custom pan-tilt mechanism setup. To accomplish the full-scale area mapping, underwater servo motors have been used in our customized pan-tilt mechanism. Once the localization is done using a custom pan-tilt mechanism, a line-of-sight optical wireless communication is established with a 200 kbps data rate. The channel is modeled based on the test pool experiments. The channel model is used to simulate underwater optical wireless communication (UOWC) to a longer link length and higher data rate. An underwater link length of 3.13 m was achieved at 1 W and 1 Gbps data rate with a Q factor of 6 and BER of 10−9. For this test setup and simulation parameters, various parameters such as BER and quality factor are examined.

Development of a Multi-User Remote Video Monitoring System Using a Single Mirror-Drive Pan-Tilt Mechanism

In this paper, we developed a concept of video monitoring system using a single mirror-drive pan-tilt mechanism. The system provides multiple zoomed videos with controllable viewing angle for each zoomed video and a wide-angle video. The system can be accessed by several users by connecting their personal computer (PC) to the server PC through the network. Every user is granted to change of their respected viewing angle of zoomed videos. The system is suitable for the remote observation deck for sight-seeing purpose. The system is composed of two high-speed cameras with wide-angle and zoomed lens, and a high-speed mirror-drive pan-tilt mechanism. The system implements a convoluted neural network-based (CNN-based) object detection to assist every user client identifying objects appearing on wide-angle and zoomed videos. We demonstrated that our proposed system is capable to provide wide-angle and zoomed videos with CNN-based object detection to four clients, where each client receives a 30 frames per second zoomed video.

Cooperative tracking in camera sensor networks with sliding mode control

This paper presents robust cooperative tracking control in camera sensor networks. We consider a camera sensor network with a Pan-Tilt (PT) mechanism whose dynamics is expressed as the Euler–Lagrange equation. We propose a distributed control law based on sliding mode control to achieve cooperative target tracking. The stability of the closed-loop system is conducted by Lyapunov's stability theory considering discontinuities of the control input. We also verify the effectiveness of the proposed method with a numerical example of synchronization of a PT camera sensor network under external disturbance.

Novel adjustable platform for camera mount

Pan-tilt mechanisms are often used as adjustable camera mounts which can be automated if required. However, existing motorized pan-tilt mechanisms are unsuitable for heavy cameras. In this study, a novel mechanism from patent MY-175792-A was adapted as a camera mount to assess its suitability as a motorized support for heavy cameras. Unlike a ball head or pan-tilt mechanism, this adjustable platform tended to change its centre of rotation as it pitched. To ensure that its stability was not compromised, various lengths of cameras were mounted on it to study changes in the centre of gravity of the system as it was pitched and yawed to different angles. This study was conducted entirely through simulation. To facilitate a seamless pan-tilt motion, the force required to slide the active joint was determined through the analysis of static equilibrium. In addition, the required torque to yaw the mount was determined through motion analysis using SolidWorks. The design proved viable as a platform for heavy cameras. It also tended to provide a natural zooming and elevating effect for its pitch motion. Its structure was stable despite simulating the longest available TV camera being pitched and yawed on it to any angle.

Assembly and testing of a pan-tilt camera mechanism for robotics visual servoing applications / Montagem e teste de um mecanismo com câmera pan-tilt para aplicações de servovisão robótica

This work is about the assembling and testing of a camera on a PAN-TILT mechanism. The prototype is also composed of two direct current (DC) motors with gearboxes, fixed to the mechanism's rotation axes. The function of the motors is to provide the necessary torques to rotate the motion axes and provide a desired orientation for the camera. The ultimate goal is to obtain a fully functional mechanism to serve as a test bench for robotics visual servoing applications and for testing future control algorithms.

Active vision for 3D indoor scene reconstruction using a 3D camera on a pan-tilt mechanism

We present a novel approach to automatic indoor scene reconstruction from RGB-D images acquired from a single viewpoint using active vision. The proposed method is designed to select the next view with sufficient information for reliable registration. The next view is selected based on the percentage of unexplored scene regions captured inside the field of view and the information content in the overlapping region between the image acquired from the next view and one of the previously acquired images. It is required that this overlapping region contains surfaces with different orientations, whose alignment provides a reliable estimation of the relative camera orientation. The point correspondences between views are established using the assumption of fixed viewpoint, imprecise information about relative view orientation and local surface normal, without need for features based on texture or distinctive local shape. After completing a scan, the 3D scene model is constructed by performing registration of the acquired depth images. Two algorithms are considered for that purpose: a point-to-plane ICP with point weighting based on the properties of the measurement noise and TEASER++. The proposed method is tested on the synthetic dataset Replica.

Integration of Smartphones Into Small Unmanned Aircraft Systems to Sense Water in Soil by Using Reflected GPS Signals

We investigate the feasibility of using built-in GNSS sensors within ubiquitous smartphone devices from a small UAS for the purpose of land remote sensing. We summarize the experimental findings and challenges that need to be resolved in order to perform the GNSS reflectometry (GNSS-R) technique via smartphones. In late 2018, a series of experiments were conducted and designed by integrating two smartphones into a multicopter UAS by attaching them to ground plates to isolate and record both direct and reflected GNSS carrier-to-noise density ratio ( $C/N_0$ ) separately. It was demonstrated that, first, fluctuations of moving GNSS specular reflections are correlated with spatial ground features with appreciable dynamic range and second, radiation pattern of the smartphone's inbuilt antenna has a significant effect on the received signal strength. In 2020, more experiments were conducted to examine the quality of in-built chip and antenna of a smartphone with regard to the GNSS-R approach as well as the consistency of measurements. These follow-up experiments involved, first, placement of the smartphone on a pan-tilt mechanism on a tripod, second, formation flights with smartphone on a gimbal and a high-quality custom-built dual-channel GNSS-R receiver, and, third, flying the UAS at different times of the day on two consecutive days. It was demonstrated that, first, the radiation pattern of the smartphone's GNSS antenna are observed to be highly irregular, but time-invariant, and, second, internal GNSS chip produces observables of sufficient quality, and, third, the fluctuations of the reflected signal are repeatable under the same configuration at different times.

Machine Vision Enabled Bot for Object Tracking

Object detection and tracking are essential and testing undertaking in numerous PC vision appliances. To distinguish the object first find a way to accumulate information. In this design, the robot can distinguish the item and track it just as it can turn left and right position and afterward push ahead and in reverse contingent on the object motion. It keeps up the consistent separation between the item and the robot. We have designed a webpage that is used to display a live feed from the camera and the camera can be controlled by the user efficiently. Implementation of machine learning is done for detection purposes along with open cv and creating cloud storage. The pan-tilt mechanism is used for camera control which is attached to our 3-wheel chassis robot through servo motors. This idea can be used for surveillance purposes, monitoring local stuff, and human-machine interaction.

PaintCopter: An Autonomous UAV for Spray Painting on Three-Dimensional Surfaces

This letter describes a system for autonomous spray painting using an unmanned aerial vehicle (UAV), suitable for industrial applications. The work is motivated by the potential for such a system to achieve accurate and fast painting results. The PaintCopter is a quadrotor that has been custom fitted with an arm plus a spray gun on a pan-tilt mechanism. To enable long deployment times for industrial painting tasks, power and paint are delivered by lines from an external unit. The ability to paint planar surfaces, such as walls in single color, is a basic requirement for a spray painting system. But this work addresses more sophisticated operation that subsumes the basic task, including painting on three-dimensional (3D) structure, and painting of a desired texture appearance. System operation consists of (a) an offline component to capture a 3D model of the target surface, (b) an offline component to design the painted surface appearance and generate the associated robotic painting commands, and (c) a live system that carries out the spray painting. Experimental results demonstrate autonomous spray painting by the UAV, doing area fill and versatile line painting on a 3D surface.

Reconnaissance for Weapon Detection and Enemy Order of Battle Awareness

Objective: This paper is about microbot for Reconnaissance (i.e. surveillance of the enemy border) which will provide early awareness of EOB (Enemy Order of Battle) to the army. The microbot will provide precise location and strength of the enemy troops. Methods: In this paper, descent control system module is used to glide the microbot to increase the time of flight. The microbot will launch using portable hand-held launcher. Telemetry receiver present in the microbot which will stream video on real time to GCS (Ground control station) is used. Findings: Physical parameters like altitude, pressure, temperature, speed, location will be transmitted to GCS. An active video module which consists of a wireless video transmitter and a pan-tilt mechanism driven by micro meters is used. Improvement: The video module is part of a miniature micro robot that is projected to areas of the environment to be surveyed. UAV microbot capable of analysis of data and real time video are featured. A perching mechanism using UAV is implemented on a < 350g flying platform which is integrated onto real flying microbot and successful perching maneuvers are illustrated as a proof of concept.

선형 반복법에 의한 이동로봇의 동시 보정

We presented a method to perform simultaneously both head-eye calibration and wheel calibration for a mobile robot that has a stereo camera mounted on the pan-tilt mechanism. Such a mobile robot system prevails recently. However, conventional methods are not applicable to this system because they assumed that camera systems were mounted on fixed structures. Building on conventional methods, we devised an iterative linear solution to solve the problem, and achieved satisfactory results in terms of accuracy in addition to efficiency due to simultaneous calibration. Furthermore, the calibration accuracy was improved by nonlinear optimization.

A Real-Time Palm Dorsa Subcutaneous Vein Pattern Recognition System Using Collaborative Representation-Based Classification

This paper describes the development of a real-time system for the recognition of a real human subject using the palm dorsa subcutaneous vein pattern (PDSVP) as a physiological biometric feature. The system has been developed using a low-cost, single board computer, called the Raspberry Pi Model B, in conjunction with an infrared sensitive camera, called the Raspberry Pi No Infrared camera, and other components. The camera is sensitive to near infrared (NIR) radiations and this acquisition property has been used to acquire the pattern of vascular structure present in the subcutaneous layer of the dorsum of the human palm. Moreover, an automatic two-axis pan-tilt mechanism has been developed on which the camera is mounted. This is a completely novel mechanism that has been developed so that the data acquisition is independent of the position where the palm dorsum is positioned, as an automatic palm dorsum self-locating strategy is developed using the two-axis pan-tilt mechanism. Now, the NIR images of the PDSVP acquired, in the aforementioned methodology, do not represent the vein pattern with appreciable clarity and discernibility. Therefore, each image acquired undergoes few steps of image preprocessing, to extract the vein pattern, before they are subjected to testing conditions or they are incorporated into the training database. The recognition strategy has been developed using the collaborative representation-based classification. In this paper, we have emphasized upon the most severe case of small sample size, which is single sample per person-based training data set creation. The proposed method is tested on a well-structured database, of NIR images of the PDSVP, JU-NIR-V1: NIR Vein Database, developed in the Electrical Instrumentation and Measurement Laboratory, Electrical Engineering Department, Jadavpur University, Kolkata, India. Subsequently, through extensive experimentation it has been proven that the proposed strategy attains substantially high and stable recognition rate. Moreover, the performance of the recognition strategy is highly robust even in the presence of artifacts, such as angular displacement and scaling, that corrupt the NIR images acquired during data acquisition.

Design of Vibration Absorber using Spring and Rubber for Armored Vehicle 5.56 mm Caliber Rifle

This paper presents a design of vibration absorber using spring and rubber for 5.56 mm caliber rifle armored vehicle. Such a rifle is used in a Remote-Controlled Weapon System (RCWS) or a turret where it is fixed using a two degree of freedom pan-tilt mechanism. A half car lumped mass dynamic model of armored vehicles was derived. Numerical simulation was conducted using fourth order Runge Kutta method. Various types of vibration absorbers using spring and rubber with different configurations are installed in the elevation element. Vibration effects on horizontal direction, vertical direction and angular deviation of the elevation element was investigated. Three modes of fire were applied i.e. single fire, semi-automatic fire and automatic fire. From simulation results, it was concluded that the parallel configuration of damping rubber type 3, which has stiffness of 980,356.04 (N/m2) and damping coefficient of 107.37 (N.s/m), and Carbon steel spring whose stiffness coefficient is 5.547 x 106 (N/m2) provides the best vibration absorption.

1P2-W08 稲作における除草ロボットの開発 : 遠隔地からの害草検知と遠隔操作のシステム構成(農業用ロボット・メカトロニクス)

Nowadays in Japan, consciousness for food safety is increasing. Therefore the vegetables made with organic farming attract attention because they are safer. However, farmers must perform extensive hand weeding in daily farming for sustaining organic farming. The weeding work hours of farmers in herbicide-free farming is five times longer than the farming uses herbicides. The autonomous mobile robot in this study helps weeding in the organic farming. The stereo camera with pan-tilt mechanism is equipped on the robot. The operator detects harmful herbs, and remotely operates the robot arm for weeding.

Control of Pan-tilt Mechanism Angle using Position Matrix Method

Control of a Pan-Tilt Mechanism (PTM) angle for the bomb disposal robot Morolipi-V2 using inertial sensor measurement unit, x-IMU, has been done. The PTM has to be able to be actively controlled both manually and automatically in order to correct the orientation of the moving Morolipi-V2 platform. The x-IMU detects the platform orientation and sends the result in order to automatically control the PTM. The orientation is calculated using the quaternion combined with Madwick and Mahony f ilter methods. The orientation data that consists of angles of roll ( α ), pitch ( β ), and yaw ( γ ) from the x-IMU are then being sent to the camera for controlling the PTM motion (pan 8 tilt angles) after calculating the reverse angle using position matrix method. Experiment results using Madwick and Mahony methods show that the x-IMU can be used to find the robot platform orientation. Acceleration data from accelerometer and flux from magneto meter produce noise with standard deviation of 0.015 g and 0.006 G, respectively. Maximum ab solute errors caused by Madgwick and Mahony method with respect to X- axis are 48.45º and 33.91º, respectively. The x-IMU im plementation as inertia sensor to control the Pan-Tilt Mechanism shows a good result, which the probability of pan angle tends to be the same with yaw and tilt angle equal to the pitch angle, except a very small angle shift due to the influence of roll angle.

IMU Application in Measurement of Vehicle Position and Orientation for Controlling a Pan-Tilt Mechanism

This paper describes a modeling and designing of inertial sensor using Inertial Measurement Unit (IMU) to measure the position and orientation of a vehicle motion. Sensor modeling is used to derive the vehicle attitude models where the sensor is attached while the sensor design is used to obtain the data as the input to control the angles of a pan-tilt mechanism with 2 degrees of freedom. Inertial sensor Phidget Spatial 3/3/3, which is a combination of 3-axis gyroscope, 3-axis accelerometer and 3-axis magnetometer, is used as the research object. Software for reading the sensor was made by using Matlab™. The result shows that the software can be applied to the sensor in the real-time reading process. The sensor readings should consider several things i.e. (a) sampling time should not be less than 32 ms and (b) deviation ratio between measurement noise (r) and process noise (q) for the parameters of Kalman filter is 1:5 (i.e. r = 0.08 and q = 0.4).

2P1-P12 ガイドロボットのための情報投影提示インタフェース : 靴の特徴を用いたユーザ識別(コミュニケーション・ロボット)

We have been developing an information projection interface for a mobile robot. The robot has a pan-tilt-zoom camera (PTZ camera) and a projector with a pan-tilt mechanism. It can project information anywhere in the environment and guide a person. The user can input commands by a simple gesture using the foot on the dialog box projected onto the floor. In this paper, we propose a method that the robot identifies the user from the persons around the robot using features of shoes; color and color differences. Experiments with ten kinds of shoes show that accuracy is about 73[%], precision is about 77[%], and specificity is about 81[%].

1A1-P03 Ubiquitous Displayによる情報投影のためのLRFを用いた位置・向き推定(コミュニケーション・ロボット)

We are developing and researching on Ubiquitous Display (UD) that is a mobile robot composed of mobile platform and a projector with pan-tilt mechanism. UD provides visual information for people by projecting images in their sight. To achieve this purpose, human's position and direction are important information for UD. In this paper, we propose a method of estimating position and direction of human by using only a single Laser Range Finder (LRF). Furthermore, we verified usefulness of the estimation method for UD's projection through experiments.