Investigation on data extraction trends for snake robot

In this paper, an investigation of snake robot movement scenario has been discussed and analyzed. Angular velocity, snake robot movement trends and motion shape are involved in this investigation by implementation of serpentine locomotion. Experiment the real snake to extract motion and force data is quite difficult to handle. Thus a new model of the test bed for robot handling and gathering data are proposed in this research. Grid like elastic strings with a particular tension are installed on the transparent table to extract the snake motion direction data to enable the snake force calculation. Then shape measurement belt and kinect sensor will establish the motion data. A snake robot is developed in this paper to perform the preparatory experimental work to go for the real snake experiment involving snake locomotion in future

Smart inertial sensor-based navigation system for flexible snake robot

The position and orientation of a robot during the navigation is a big challenge to the researchers. The received signal strength information (RSSI) of Wifi or Bluetooth or RFID is the available way to solve this issue for the localization researches. But the obstacles in the environment are very big challenge for this technology. RSSI should be vulnerable depends on the obstacle, if it is dynamic environment then there is nothing to say about this signal. Thus inertial sensors like accelerometer and rate gyro are chosen for flexible snake robot localization in planar surface navigation. This paper describes the methods of navigation positioning system using inertial sensor and finally, perform the experiment with the flexible snake robot for indoor position and orientation

Autonomous reconnaissance mission: development of an algorithm for collaborative multi robot communication

A collaborative team of two resource constrained semi-autonomous hexapod robots have been developed that perform navigation tasks while satisfying communication constraints. Our approach is based on the use of a control structure where each hexapod performs elementary tasks, a behavior-based controller generates motion directives to achieve the collaborative tasks, and controller generates the actuator commands to follow the motion directives. The control technique has been developed for a mission where a target location spread across a static environment has to be visited once by the two hexapods while maintaining a relative given distance with wireless communication. Wireless communication under mobile ad-hoc networks are communication networks that do not rely on fixed, preinstalled communication devices like base stations or predefined communication cells. This wireless networks consist of mobile nodes which are characterized by their decentralized organization and the potentially high dynamics of the network structure, therefore ad-hoc network communication system has been the focus in this multi-robot communication. The ad-hoc network has to provide position data to support localization of the mobile robots, which might be of great importance to guide the robots to specific targets and locations. Communications standards considered for the ad-hoc network are Wireless LAN, Bluetooth and ZigBee. In this project Bluetooth and ZigBee are integrated on robots for real experiments

Ready Made Garments’ (RMG) Contribution in Women Empowerment: A Study on Bangladesh Perspective

There is no denying the fact that without women empowerment development goals of Bangladesh is always unreachable. This country belongs to a social system where women consider as a burden for the family. However, the scenario is changing with time. Nowadays, women are working in garments sector, education sector, banking sector, different NGO’s and government organizations but the single garment sector where seventy percent of workers of 4.0 million are women and most of them are less educated, unskilled and from rural areas. These women have neither decision making power and nor access to resources before getting the job in the garments sector. The job creates ample opportunity for female workers by giving economic freedom, keeping them near the resources and facilities in the city area, and making them knowledgeable, and skills through training, counseling, and sharing problem with coworkers. The study reveals that empowerment of women vastly depends on four variables which are women’s financial contribution to family, women’s access to resources, women’s participation in household decision making and their perception of coping capacity to shocks. It has been found that garments sector significantly contribute to enhance the female worker’s ability to contribute financially, to participate in decision making, to access resources, and to cope with risks which ultimately increase their empowerment in the society as a whole

Repairing and commissioning of an AC motor speed controller for a centrifugal pump

A centrifugal pump was installed in 1984 in the Fluid Mechanics Laboratory of Mechanical Engineering Department of Rajshahi University of Engineering & Technology. The motor of the centrifugal pump was dc motor and was not working. It could not be commissioned for a long time because of the damaged speed controller. The main shaft (rotor) was also jammed. In this project work, the dc motor was tried to repair. But it could not be run because the specification of the motor and the operating manual was not available. To complete the project successfully, the dc motor was replaced by an ac induction motor. After replacing the motor, the speed of the new motor was controlled by a variable frequency drive (VFD). Using this device, the speed was controlled from 600 rpm to 3000 rpm smoothly. After the replacement, the testing of the centrifugal pump was successfully performed and the motor was controlled in various speeds. Experiment on the performance test of the centrifugal pump was carried out satisfactorily running the pump in various speeds operated by the VFD

Acacia Catechu Trees in Rice Fields: A Traditional Agroforestry System of Northern Bangladesh

Growing Acacia catechu trees on rice fields is one traditional crop-land Agroforestry system of Rajshahi region in Bangladesh. Farming system was explored with detailed information on farm operations and cropping calendar including system outputs. System dynamics was also evaluated. PRA exercises were conducted for a biophysical assessment. The information was collected on informant wise and cross-checked. Best growth of trees observed under rain-fed conditions. Higher density of trees found in un-irrigated fields. Trees were better managed in small plots. In general, density of khoir trees was found higher in small holdings (less than 2 ha) with secured land tenure. Trees on farms were of uneven age indicating the khoir + rice system biologically sustainable. The ease of establishment of Khoir seedlings, the low cost of its maintenance, and less vulnerability to any serious pest or disease, easy marketability of products rated high in the farmer’s preference for khoir. They appreciate the versatility of the wood for a variety of farm uses though its prime economic use to them is for production of lali for katha. They also get pitch khoir as by product of katha (red dyestuff for textiles and paper) production. The multiple products and services offered and the ease of managing the trees on crop fields without causing any immediate or long-term reduction in crop yield seemed to be the most important factors that encourage the farmers to continue this traditional practice. If farmers could be motivated to follow appropriately the silvicultural practices, production could further be increased

Smart Tendon Actuated Flexible Actuator

We investigate the kinematic feasibility of a tendon-based flexible parallel platform actuator. Much of the research on tendon-driven Stewart platforms is devoted either to the completely restrained positioning mechanism (CRPM) or to one particular type of the incompletely restrained positioning mechanism (IRPM) where the external force is provided by the gravitational pull on the platform such as in cable-suspended Stewart platforms. An IRPM-based platform is proposed which uses the external force provided by a compliant member. The compliant central column allows the configuration to achieve n DOFs with n tendons. In particular, this investigation focuses on the angular deflection of the upper platform with respect to the lower platform. The application here is aimed at developing a linkable module that can be connected to one another so as to form a “snake robot” of sorts. Since locomotion takes precedence over positioning in this application, a 3-DOF Stewart platform is adopted. For an arbitrary angular displace of the end-effector, the corresponding length of each tendon can be determined through inverse kinematics. Mathematical singularities are investigated using the traditional analytical method of defining the Jacobian

Hexagonal structure hexapod robot: developing a method for omni-directional navigation

In this paper, we propose a method that allows a hexapod robot to navigate omni-directionally with hexagonal structure. Typical body structures for hexapod robot are analyzed. Hexapod robot frequently navigates various directions over variety of surfaces. To enable locomotion in rough surface, hexapod must be able to stably move in any direction. A comparative study, based on different model of hexapod for omni-directional navigation, concludes that the hexagonal hexapod robot can be able to navigate omni-directionally on the complex surface. Finally, a method is developed for omni-directional navigation of the hexapod robot