An Interactive Auto-recharging System for Mobile Robots

The article develops a vision based auto-recharging system for mobile robots, and programs a new docking processing to enhance successful rate. The system contains a docking station and a mobile robot. The docking station contains a docking structure, a control device, a charger and a detection device and a wireless RF interface. The mobile robot contains a power detection module (voltage and current), an auto-switch, a wireless RF interface, a control system and a camera. The docking structure is designed with one active degree of freedom and two passive degrees of freedom. The active degree of freedom can move forward to contact the recharging connect points that are arranged in the mobile robot. The two passive degrees of freedom can rotation in the Z-axis and use compression spring moving on various docking condition. In image processing, the mobile robot uses a webcam to capture the real-time image; and transmits the image signal to the computer via USB interface, and uses Otsu algorithm to recognize the position of the docking station. In the experiment results, the system had been successfully guided the mobile robot moving to the docking station using the proposed method.

Urgency of the research. Automatic battery charging of AGV platforms allows you to maximize their potential. Safe and quickly positioning AGVs in a charging station equipped with appropriate contacts, reduces the charging time as well as the purchase price of the device. Target setting. The aim of the solution is to design an automatic docking and charging station from a used hand-held charging station. In the design, it was necessary to ensure the appropriate position of the AGV platform against the docking station. Actual scientific researches and issues analysis. The issue of fast and reliable charging of mobile service robots is highly up-to-date. The reason for this is the growing deployment of AGV platforms in various industrial or service sectors. Uninvestigated parts of general matters defining. This article focuses on a specific solution for the provision of transport services. Transport services come from the need to transport medical supplies and medications in a multi-storey hospital building. The movement of the robot between the floors is solved by the use of lifts used by the personal of hospital. The research objective. The aim of the research was to design a docking and charging station utilized an already purchased power-up charger. The design was aimed at creating an appropriate power transmission system between the charger and the AGV platform batteries. The price ceiling for the whole facility was worth € 2,000. The statement of basic materials. The use of docking and charging stations for mobile service robots is dependent on a number of parameters. In particular, the parameters depend on the area of use, the size of the battery to be charged, and the amount of robots being recharged at the station. Last but not least, charging time and purchase price are also important. Conclusions. The task of the solution was to design a docking station design for the AGV platform. At the beginning, three variants were created, from which the most appropriate solution was chosen using the scoring method. However, before designing the docking station design, it was necessary to modify the existing AGV platform construction so that it could be connected to the docking station charging mechanism. The design of the docking station itself consisted of the design of the charging and charging mechanism. These mechanisms provide charge and guidance of the AGV platform to the docking station. Mechanisms are not dependent on each other, since the charging mechanism is activated later than the drive mechanism. Subsequently, a design of the docking station, which can be anchored to the floor or to the wall, was created. At the docking station there is a charger from Hoppecke, which provides the AGV platform charging. The design dimensions of the docking station have been greatly influenced by the size of the above-mentioned charger. It has been found that new and better technologies will not be needed at the docking stations in the future, as AGV platforms can be guided without their help. The development of new and better quality systems will bring new guidance options to AGV platforms and docking stations.

We present path-planning techniques for a multiple mobile robot system. The mobile robot has the shape of a cylinder, and its diameter, height, and weight are 8 cm, 15 cm, and 1.5 kg, respectively. The controller of the mobile robot is an MCS-51 chip, and it acquires detection signals from sensors through I/O pins. It receives commands from the supervising computer via a wireless RF interface, and transmits the status of the robots to the supervising computer via a wireless RF interface. The mobile robot system is a module-based system, and contains a controller module (including two DC motors and drivers), an obstacle detection module, a voice module, a wireless RF module, an encoder module, and a compass detection module. We propose an evaluation method to arrange the position of the multiple mobile robot system, and develop a path-planning interface on the supervising computer. In the experimental results, the mobile robots were able to receive commands from the supervising computer, and to move their next positions according to the proposed method.

The paper develops a fire detection system using mobile robots, and calculates the risk values of the escaping paths using Bayesian estimated method. Mobile robots contain two types moving in the platform. One is fire detection robot (FDR) to search fire sources. The other represents the people walking in the platform autonomously. The controller of the mobile robot detects fire source using flame sensor, and receives the motion command from the supervised compute via wireless RF interface. The mobile robot transmits ID code, position and orientation information, positions of fire sources to the supervised computer via wireless RF interface, too. We program the motion path of fire detection robots to search fire sources, and uses Gauss distribution function to describe the risk values of each fire source. The supervised computer uses Bayesian estimated algorithm to calculate the relation risk value of each cross point for multiple fire sources. In the fire condition, each FDR calculates shortest displacement from the people. The assigned FDR carries the people leaving the dangerous area. Then the user interface programs the escaping paths using A* searching algorithm for mobile robots. The mobile robot guides the people (mobile robot) leaving the fire area according the programmed safety escaping path.

The article develops multi-pattern formation exchange using A* searching algorithm, and programs the shortest motion paths for mobile robots. The system contains an image recognition system, a motion platform, some wireless RF modules and five mobile robots. We use Otsu algorithm to recognize the variety 2D bar code to classify variety pattern, and control five mobile robots to execute formation exchange, and present the movement scenario on the motion platform. We have been developed some pattern formations according to game applications, such as hook pattern formation, T pattern formation, L pattern formation, rectangle pattern formation, sward pattern formation and so on, and develop the user interface of the multi-robot system to program motion paths for variety pattern formation exchange on the supervised computer. The supervised computer programs pattern formation exchange according to the image recognition results, and controls mobile robots moving on the motion platform via wireless RF interface. In the experimental results, mobile robots can receive the pattern formation command from the supervised computer, and change the original pattern formation to the assigned pattern formation on the motion platform, and avoid other mobile robots on real-time.

The article presents multiple pattern formation control of the multi-robot system using A* searching algorithm, and avoids the collision points moving on the motion platform. We use speech recognition algorithm to decide the various pattern formations, and program mobile robots to present the movement scenario on the grid-based motion platform. We have been developed some pattern formations to be applied in game applications, such as long snake pattern formation, phalanx pattern formation, crane wing pattern formation, sword pattern formation, cone pattern formation and so on. The mobile robot contains a controller module, three IR sensor modules, a voice module, a wireless RF module, a compass module, and two DC servomotors. The controller of the mobile robot can acquire the detection signals from reflect IR sensor modules and the compass module, and decide the cross points of the aisle. The mobile robot receives the command from the supervised computer, and transmits the status of environment to the supervised computer via wireless RF interface. We develop the user interface of the multi-robot system to program motion paths for various pattern formation exchanges using the minimum displacement. Users can use speech to control the multiple mobile robots to execut pattern formation exchange. In the experimental results, users can speak the pattern formation. The speech recognition system receives the signal to decide the pattern formation. The multiple mobile robots can receive the pattern formation command from the supervised computer, and arrange the assigned pattern formation on the motion platform, and avoid other mobile robots.

To provide post-stroke patients with rehabilitation training, this paper presents a six degrees of freedom (DOF) cable-driven upper limb exoskeleton, where 3 active DOF, 1 active DOF, and 2 passive DOF are given to the shoulder, elbow, and wrist, respectively. Carbon fiber materials are mainly used to consist of the frame of the prototype, achieving the lightness and compactness design. Cable-driven series elastic actuators are used to minimize the inertia and complexity of the exoskeleton’s joints and provide compliant actuation, resulting in better human-robot interaction. A double parallelogram mechanism is designed to transfer rotation from a remote center to the glenohumeral joint. To evaluate the performance of the prototype, PID controllers are designed to conduct position tracking and torque tracking experiments in the elbow joint. The experimental results show that the prototype has a good tracking performance and is capable to assist patients in rehabilitation training.

Mobile robot localization and map building are very important for a mobile robot to perform a navigation-based service task to aid the aged or disabled in an indoor environment (office, facilities or at home). In order to enable mobile robot to perform service tasks autonomously, the information of environment in which the mobile robot moves is needed. To obtain the accurate map, many different sensors system and techniques have been developed. Approaches of mapping can roughly be classified according to the kind of sensor data processed and the matching algorithms [S. Thrun et al., 1996, 1998, 2000, 2004; Chong, K.S et al., 1996; C.-C. Wang et al., 2002; G. Dissanayake et al., 2000; B. barshan et al., 1995; Weimin Shen et al., 2005]. In this paper, we proposed a method of map building using interactive GUI for a mobile robot. The reason we proposed this method is that it is difficult for a mobile robot to generate an accurate map although many kinds of sensors are used. The proposed method enables the operator to modify map built by sensors, compared with the real-time video from web camera by using modification tool in interactive GUI. Laser Range Finder (LRF) was used to get the information of the environment in which mobile robot moving. In order to improve self-localization of mobile robot, Extended Kalman Filter (EKF) was introduced. By the results of simulation and experiments, the developed EKF is effective in self-localization of mobile robot. This paper introduces the architecture of the system and gives some experimental results to verify the effectiveness of the developed system. The rest of the paper consists of 5 sections. Section 2 describes the structure of the proposed system. Section 3 presents the developed algorithm of self-localization of mobile robot and gives some simulation and experimental results to verify the effectiveness of the EKF in improving precision of positioning of mobile robot. Section 4 details the developed LRF data processing algorithm. Section 5 introduces the developed interactive GUI. The experimental results are given in Section 6. Section 7 concludes the paper. 13

A new three-dimensional (3D) map building method based on Laser Range Finder (LRF) has been proposed in this research, performing a surface estimation with the Iterative Closest Point (ICP) algorithm. While a mobile robot is navigating in an unknown environment, the entire environment cannot be scanned by LRF since kinematic features of the mobile robot and surface conditions are dynamically changing. To resolve this difficulty in building a 3D map while the mobile robot is navigating, a surface estimation ICP algorithm is proposed, which is based on the continuity of the environment around mobile robot. That is, this new algorithm recovers the un-scanned area by estimating feature points in the neighboring two regions based on the continuous environment information. The effectiveness of proposed algorithm has been demonstrated through real experiments of the mobile robot navigation.

The security system of home and building is an important issue to human daily life. We develop a multiple remote interface security system (MRlSS), that integrated with intelligent security robot (ISR), security supervise computer, GSM module, RF interface and appliances control module. The multiple remote interface security system can detect abnormal and dangerous situation and notify us through Internet, or send the message to cellular phone through GSM module. The MRISS can control the appliance control module using wireless RF interface. The user can remote control appliance using cell phone through GSM module, too. The appliance module can feedback reaction result to the user through cell phone. First, we develop the communication protocol in MRISS, and design the multiple interface security robot, security module and appliance control module. Then we implement the MRISS function using the proposed method applying in security detection and appliance control. We can monitor the condition in home or building through Internet, and receive a message of the detection information to cellular phone using wireless RF interface embedded in the ISR. We can also use cell phone to instruct ISR to control appliances. ISR controls appliances via wireless RF module. We have developed and demonstrated the success of the project presented situation here in.

The design of the LEESD, a new exoskeleton for old people and patients, is presented in this paper. With one active degree of freedom (DOF) and two passive degrees of freedom, the LEESD can realize human walking gait. The hip joints and knee joints of the LEESD are directly driven by four-bar linkages and all these four-bar linkages are driven by merely one brushless DC motor which rotates at a constant speed. Considering these features, LEESD is a simple, as well as affordable mechanism. The details of the LEESD have been rigorously discussed and calculated during the design process.

Robust simultaneous localization and map building (SLAM) is a key issue for mobile robot in presence of faults. In the paper, an adaptive evolutionary particle filter is designed to achieve robust SLAM for wheeled mobile robot when the laser range finder is subjected to errors. Firstly, a robust perception model for laser range finder is presented. The robustness of the provided model is two folds, (1) error beams of laser range finder are filtered out with segment analysis method, and (2) beams occluded by dynamical objects are filtered out with a high pass filter. Secondly, an adaptive mutation scheme is adopted to recover the diversity of the particles after resampling stage. Lastly, the presented method is testified in a real mobile robot.

This paper proposes map building method. Sensors such as a laser range finder, a gyroscope, encoders multiply compose the system. Generally, mobile robot can measure its relative position using a gyroscope and encoders in an environment. However, in this case, a large number of errors occur due to accumulative errors of sensor over time. Therefore, a map based on feature points is used. And an absolute position is measured by the feature points and geometrics. As combining the relative position and the absolute position, mobile robot can recognize its position. According to compositional data of a map, in case of a laser range finder, it takes a long time when adding a map or calculating a position of mobile robot. Therefore, it is necessary to arrange the feature points for computational time and map building. In this paper, a map was formed by laser range finder and features of geometrics. As a result of proposed method, the map was built efficiently in an aspect of time.

Understanding the dynamics of two inertial bodies coupled via a friction interface is essential for a wide range of systems and motion control applications. Coupling terms within the dynamics of an inertial pair connected via a passive frictional contact are non-trivial and have long remained understudied in system communities. This problem is particularly challenging from a point of view of modeling the interaction forces and motion state variables. This paper deals with a generalized motion problem in systems with a free (of additional constraints) friction interface, assuming the classical Coulomb friction with discontinuity at the velocity zero crossing. We formulate the dynamics of motion as the closed-form ordinary differential equations containing the sign operator for mapping both, the Coulomb friction and the switching conditions, and discuss the validity of the model in the generalized force and motion coordinates. The system has one active degree of freedom (the driving body) and one passive degree of freedom (the driven body). We demonstrate the global convergence of trajectories for a free system with no external excitation forces. Then, an illustrative case study is presented for a harmonic oscillator with a frictionally coupled second mass that is not grounded or connected to a fixed frame. This simplified example illustrates a realization and main features of the proposed (general) modeling framework. Some future development and related challenges are discussed at the end of the paper.

Human-following in a cluttered environment is one of the challenging issues for mobile service robot applications. Since a laser range finder (LRF) is commonly installed for autonomous navigation, it is advantageous to adopt an LRF for detection and tracking humans. In this paper, we aim at the reliable human tracking performances in a dynamic cluttered environment. The key idea is to develop a hierarchical sample-based joint probabilistic data association filter (HSJPDAF) by focusing on the leg positions as well as human positions. The proposed HSJPDAF consists of two levels in order to consider the interdependence between targets. Possible locations of multiple human targets can be simultaneously estimated on the basis of Bayesian filtering. Comparison with the general technique was carried out to verify the performance of HSJPDAF in both artificial indoor and real-world environments. Owing to the hierarchical framework, the proposed method shows the improved robustness by reducing the target loss rate significantly in a dynamic cluttered environment.