Guifang Qiao

An indoor security system with a jumping robot as the surveillance terminal

Mobile robots are now widely used in various surveillance and security applications. But most of them are wheeled and tracked robots that can not work well to overcome stairs, doorsills and other obstacles in cluttered indoor environments. This paper presents the design and implementation of a new indoor security system with a jumping robot as the surveillance terminal. The jumping robot, a gateway and some pyroelectric infrared (PIR) sensor nodes form a ZigBee wireless sensor network (WSN). The sensor nodes are installed above the doors and windows of the house to detect intruders and send intrusion detection messages to the robot. The robot can jump to the sensor coverage area to take photos and send them to the gateway and the home server. The remote house owner will get these photos through Internet. A prototype system has been implemented and some performance tests have been done. Experimental results show that the robot can jump up on a desk of 105cm high to perform the surveillance task. A 3k-byte captured photo can be transmitted to the gateway in 3.68s with 0.1% loss rate by 5 hops1.

Autonomous network repairing of a home security system using modular self-reconfigurable robots

Traditional wheeled robots cannot easily adapt to complex home environments with stairs and doorsills. This paper presents the design and implementation of a novel wireless sensor network based home security system with a modular self-reconfigurable robot (Transmote) as the mobile node. The security system is composed of some static monitoring nodes, a Transmote, and a home server. Static nodes with pyroelectric infrared (PIR) sensor and digital camera are mounted on doorframes and windows to detect intruders and send intrusion alarm messages to the home server. Transmote with PIR sensor and camera can patrol in the house for security surveillance. Transmote also can provide network repairing service when some static router nodes fail. Transmote modules and static monitoring nodes are controlled by two different wireless sensor networks. The remote house owner can get the alarm messages through Internet. Transmote can transform into I-shaped or O-shaped configuration according to different locomotion requirements. A prototype system has been implemented and some performance tests have been done. Experimental results show that the I-shaped Transmote can pass through an 8.8 cm high and 10 cm wide channel. The velocity of the I-shaped Transmote is up to 3 m/min and the maximum velocity of O-shaped Transmote is 9.3 m/min. A 12 kB captured photo can be transmitted to the gateway through 15 hops without any packet loss.

A Modular Self-Reconfigurable Robot with Enhanced Locomotion Performances: Design, Modeling, Simulations, and Experiments

This paper presents the design and implementation of a modular self-reconfigurable robot with enhanced locomotion capabilities. It is a small hexahedron robot which is 160 mm × 140 mm × 60 mm in size and 405 g in weight. The robot is driven by three omnidirectional wheels, with up and down symmetrical structure. The robot can perform rectilinear and rotational locomotion, and turn clockwise and counterclockwise without limitation. A new docking mechanism that combines the advantages of falcula and pin-hole has been designed for attaching and detaching different modules. The communication and image data transmission are based on a wireless network. The kinematics and dynamics of the single module has been analyzed, and the enhanced locomotion capabilities of the prototype robot are verified through experiments. The maximum linear velocity is 25.1cm/s, which is much faster than other modular self-reconfigurable robots. The mobility of two connected modules is analyzed in the ADAMS simulator. The locomotion of the docking modules is more flexible. Simulations on the wheel and crawling locomotion are conducted, the trajectories of the robot are shown, and the movement efficiency is analyzed. The docking mechanisms are tested through docking experiments, and the effectiveness has been verified. When the transmission time interval between the adjacent packets is more than 4 ms, the wireless network will not lose any packet at the maximum effective distance of 37 m in indoor environments.

Battery swapping and wireless charging for a home robot system with remote human assistance

This paper presents a battery swapping and wireless charging robot system. A six degree-of-freedom manipulator mounted on a four-wheeled robot base is used to grasp the dead battery in the robot and plug it into a charger on a wireless charging station for recharging. A camera mounted on the robot provides visual information to help the user control the robot remotely through any user terminals with Internet connections. The robot sends visual information to a home server through a Wi-Fi network. The server transmits visual information to the user through the Internet. The user can control the robot to move to the position near the charging station and swap the dead battery with a charged one. A prototype system has been implemented and some performance tests have been done. Experimental results show that the peak current of wireless charging of the system is about 725 mA. The charging time for a 4000 mAh battery is about 8 hours with the average charging efficiency of 46.4%. The video data transmitting speed through the Wi-Fi network is about 14 frames per second. The robot can swap its battery in about 62 s with human assistance.

Self-righting, steering and takeoff angle adjusting for a jumping robot

This paper presents a 9 cm × 7 cm × 12 cm, 154 g jumping robot with self-righting, steering, and takeoff angle adjusting capabilities. The quick energy releasing function of the jumping mechanism is implemented by using an eccentric cam. The self-righting, steering, and takeoff angle adjusting capabilities are achieved by adding a rotatable pole leg. The pole leg can prop up the body of the robot when it falls down. The pole leg can also steer the robot to turn at a step of about 24°. By adjusting the center of mass (COM), the robot can jump at different takeoff angles. Experimental results show that the constructed robot can jump more than 88 cm high at a takeoff angle of 82.7° and it can continuously jump to overcome stairs.

Design and Implementation of a Modular Self-reconfigurable Robot

This paper presents the design and implementation of a new modular self-reconfigurable robot. The single module has three joints and can perform rectilinear motion, lateral shift, lateral rolling, and rotation. A flexible pin-hole-based docking mechanism is designed for self-assembly. With the proposed infrared-sensor-based docking method, multiple modules can be self-assembled to form versatile configurations. The modules communicate with each other through ZigBee protocols. The locomotion planning and geometry analysis of the single module are presented in detail and the efficiency of the single modules mobility is also demonstrated by experimental results. In automatic docking experiments with two modules, the proposed method is shown to be able to achieve an average success rate of 78% within the effective region. The average time of the docking process is reduced to 75 s. The maximum velocity of the I-shaped robot is up to 3.6 cm/s and the maximum velocity of the X-shaped robot is 4.8 cm/s. The detach-dock method for I-to-X transformation planning is also verified. The ZigBee-based communication system can achieve 100% receiving rate at 55 ms transformation interval.

Wheeled robot control based on gesture recognition using the Kinect sensor

Human Machine Interaction (HMI) plays a very important role in intelligent service robot research. Traditional HMI methods such as keyboard and mouse cannot satisfy the high demands in some environments. To solve this problem, many researchers pay attention to vision-based gesture recognition research recently. This paper proposes a simple method to control the movement of a robot based on Kinect which provides skeleton data with low computation, acceptable performance and financial cost. The method can recognize eleven defined gestures by using the coordinates of joints, which are obtained from the skeleton model provided by the Kinect SDK. A Khepera III robot is used as a prototype control object, to verify the effectiveness of the proposed method. The experimental results show that the success rate of gesture recognition is over 96%. The proposed method is robust to work in real-time.

A Wireless Sensor Network System with a Jumping Node for Unfriendly Environments

Mobile robots have been adopted to repair failed wireless sensor network systems for node damage, battery exhaustion, or obstacles. But most of the robots use wheeled locomotion manner, which does not work well or even fails when confronted with obstacles in uneven terrains. To solve this problem, this paper presents the design of a jumping robot to serve as a robotic node for wireless sensor networks. The robot can jump up to or over obstacles to repair the broken network connections. The robot senses its posture angle by using an acceleration sensor and self-rights automatically by using a pole leg after falling down on the ground. The robot also can steer and adjust its take-off angle by the pole leg. A network monitoring system with the proposed robot is built to test its basic locomotion capabilities and the network repair function. Experimental results show that the robot can jump about 90 cm in height and traverse 50 cm far at a take-off angle of 75 degrees. The robot can repair the network by jumping up to a 10 cm high platform. The proposed system with a jumping node can provide powerful support for applications in unfriendly environments.

Design and Implementation of a Remote Control System for a Bio-Inspired Jumping Robot:

This paper presents the design and implementation of a remote control system for a bio-inspired jumping robot. The system is composed of a server, a gateway, and a jumping robot. The proposed remote control system is used to monitor the posture of the jumping robot and control it in remote places. A three-axis accelerometer is used to detect the tilts of the robot. A compass is used to sense the azimuth of the robot. The calibrations of the accelerometer and the compass are conducted. The sensor data of the robot can be sent to the server through a ZigBee wireless sensor network (WSN). An algorithm is designed to calculate the posture of the robot from the sensor data. The posture of the robot can be displayed on the human-computer interface of the server using the virtual reality technology of OpenGL. The robots can be controlled by the operator through the interface. Two experiments have been done to verify the posture detection method and test the performance of the system.

Hand Motion-Based Remote Control Interface with Vibrotactile Feedback for Home Robots

This paper presents the design and implementation of a hand-held interface system for the locomotion control of home robots. A handheld controller is proposed to implement hand motion recognition and hand motion-based robot control. The handheld controller can provide a ‘connect-and-play’ service for the users to control the home robot with visual and vibrotactile feedback. Six natural hand gestures are defined for navigating the home robots. A three-axis accelerometer is used to detect the hand motions of the user. The recorded acceleration data are analysed and classified to corresponding control commands according to their characteristic curves. A vibration motor is used to provide vibrotactile feedback to the user when an improper operation is performed. The performances of the proposed hand motion-based interface and the traditional keyboard and mouse interface have been compared in robot navigation experiments. The experimental results of home robot navigation show that the success rate of the handheld controller is 13.33% higher than the PC based controller. The precision of the handheld controller is 15.4% more than that of the PC and the execution time is 24.7% less than the PC based controller. This means that the proposed hand motion-based interface is more efficient and flexible.