Aliakbar Akbari

Ontological physics-based motion planning for manipulation

Robotic manipulation involves actions where contacts occur between the robot and the objects. In this scope, the availability of physics-based engines allows motion planners to comprise dynamics between rigid bodies, which is necessary for planning this type of actions. However, physics-based motion planning is computationally intensive due to the high dimensionality of the state space and the need to work with a low integration step to find accurate solutions. On the other hand, manipulation actions change the environment and conditions further actions and motions. To cope with this issue, the representation of manipulation actions using ontologies enables a semantic-based inference processe that alleviates the computational cost of motion planning. This paper proposes a manipulation planning framework where physics-based motion planning is enhanced with ontological knowledge representation and reasoning. The proposal has been implemented and is illustrated and validated with a simple example. Its use in grasping tasks in cluttered environments is currently under development.

Task and motion planning using physics-based reasoning

For everyday manipulation tasks, the combination of task and motion planning is required regarding the need of providing the set of possible subtasks which have to be done and how to perform them. Since many alternative plans may exist, the determination of their feasibility and the identification of the best one is a great challenge in robotics. To address this, this paper proposes: a) a version of GraphPlan (one of the best current approaches to task planning) that has been modified to use ontological knowledge and to allow the retrieval of all possible plans; and b) a physics-based reasoning process that determines the feasibility of the resulting plans and an associated cost that allows to select the best one among them. The proposed framework has been implemented and is illustrated through an example.

Integration of RFID and WSN for supply chain intelligence system

Radio Frequency Identification (RFID) system is used for detecting and identifying the tagged objects by electromagnetic signals. Wireless Sensor Networks (WSN), which consists of a huge numbers of nodes, can monitor the condition of the environment including pressure, humidity, and temperature. Data is transferred via nodes to a certain location. Integration of RFID and WSN provides a new feature and improves their functionalities. In the RFID system, each tag can only communicate with a reader. By integrating RFID tags with nodes, communication of the RFID tags with each other is possible and also integration of readers with nodes facilitates negotiation of readers together. The RFID and WSN integration in supply chain provides system intelligence. In such a case, tag is embedded in objects and reader is integrated with nodes. Therefore, identification and detection of tagged items is provided by using RFID and monitoring of environment can be obtained by using WSN. The present case study is simulated in the Petri Net Toolbox in MATLAB environment. It represented the negotiation of smart devices spontaneously in managing variety of instructions in order to enhance system performance.

Reasoning-based evaluation of manipulation actions for efficient task planning

To cope with the growing complexity of manipulation tasks, the way to combine and access information from high- and low-planning levels has recently emerged as an interesting challenge in robotics. To tackle this, the present paper first represents the manipulation problem, involving knowledge about the world and the planning phase, in the form of an ontology. It also addresses a high-level and a low-level reasoning processes, this latter related with physics-based issues, aiming to appraise manipulation actions and prune the task planning phase from dispensable actions. In addition, a procedure is contributed to run these two-level reasoning processes simultaneously in order to make task planning more efficient. Eventually, the proposed planning approach is implemented and simulated through an example.

Comparison of wireless sensor network and radio frequency identification for the process control of distributed industrial systems

In today’s demanding market, flexibility and reconfigurability play an important role in manufacturing industries. This can be achieved by employing distributed control system such as International Electrotechnical Committee 61499 function block, which is a new standard adopted for industrial-process measurement and control system. On the other hand, wireless systems have been adopted recently in manufacturing systems as a replacement for conventional wired systems. This includes the wireless sensor network and radio frequency identification, which are emerging technologies adopted recently in a wide range of applications, especially in industry sectors. This article presents and compares the application of wireless sensor network and radio frequency identification in the process control of industrial system on the basis of International Electrotechnical Committee 61499 standard. Two process control architectures are considered for a case of an assembly line in order to compare and measure performance by employing Petri net as a mathematical modelling tool.

Physics-Based Motion Planning: Evaluation Criteria and Benchmarking

Motion planning has evolved from coping with simply geometric problems to physics-based ones that incorporate the kinodynamic and the physical constraints imposed by the robot and the physical world. Therefore, the criteria for evaluating physics-based motion planners goes beyond the computational complexity (e.g. in terms of planning time) usually used as a measure for evaluating geometrical planners, in order to consider also the quality of the solution in terms of dynamical parameters. This study proposes an evaluation criteria and analyzes the performance of several kinodynamic planners, which are at the core of physics-based motion planning, using different scenarios with fixed and manipulatable objects. RRT, EST, KPIECE and SyCLoP are used for the benchmarking. The results show that KPIECE computes the time-optimal solution with heighest success rate, whereas, SyCLoP compute the most power-optimal solution among the planners used.

Implementation of structural health monitoring based on RFID and WSN

Structural Health Monitoring (SHM) plays an extremely substantial role in various structures in terms of collecting observation of environmental conditions as well as detecting failures. The present study demonstrates the algorithm for the process of SHM by applying integration of Radio Frequency Identification (RFID) system with sensor-tags in order to indicate how communication is carried out throughout the system. Two methods are proposed in which integration-based model of RFID and Wireless Sensor Nodes (WSN) is firstly investigated for bridge application and incorporation of RFID with passive sensor-tags is secondly employed for structural health monitoring. Regarding the latter method, the implementation model is offered with the purpose of demonstrating the system performance simulated in Petri net toolbox.

Application of RFID system for the process control of distributed manufacturing system

Radio-Frequency Identification (RFID) has emerged as a notable technology among industrial manufacturers to develop automation systems. It caters the unique identification number with conforming international global standards for each tagged object which is traced. The aim of the present study is to contribute a framework based on RFID application for the process control of manufacturing system in order to enhance productivity, efficiency, utilization, as well as decreasing idle time of system. The model is comprised of production system which can be quite well integrated with RFID system. The main role of this technology is to process data captured by RFID gates. Applying this technology makes possibility to manage workflows of transportation lines in terms of various products types. Finally, the implementation of system is analyzed by employing MATLABs Petri Net toolbox.

Comparison of RFID system and barcode reader for manufacturing processes

Recently, automated identification system has been playing an important role in industry for different types of process and there are different ways, ex. applying Radio Frequency Identification (RFID) or barcode scanner to detect tagged items. This study is going to evaluate significant difference of RFID system and barcode scanner for the manufacturing process. The main aim is to show the efficient process which is performed by applying RFID instead of barcode system to enhance productivity and decrease idle time of workstations.

Task planning using physics-based heuristics on manipulation actions

In order to solve mobile manipulation problems, the efficient combination of task and motion planning is usually required. Moreover, the incorporation of physics-based information has recently been taken into account in order to plan the tasks in a more realistic way. In the present paper, a task and motion planning framework is proposed based on a modified version of the Fast-Forward task planner that is guided by physics-based knowledge. The proposal uses manipulation knowledge for reasoning on symbolic literals (both in offline and online modes) taking into account geometric information in order to evaluate the applicability as well as feasibility of actions while evaluating the heuristic cost. It results in an efficient search of the state space and in the obtention of low-cost physically-feasible plans. The proposal has been implemented and is illustrated with a manipulation problem consisting of a mobile robot and some fixed and manipulatable objects.