Omar M. Al-Jarrah

Arm-manipulator coordination for load sharing using variable compliance control

Coordination of a human arm and a manipulator to share a load is a new problem. In this paper, we propose a variable compliance control as a coordination mechanism for the arm and the manipulator. The compliance will be updated according to the force exerted by the manipulator. This coordination mechanism is proposed to accommodate with the uncertainties associated with the impedance of the human arm and the weight of the object. Furthermore, the stability of the system and the manipulation speed will be improved. The stability problem is studied using the small gain theorem. Experiments were conducted in our laboratory to prove the effectiveness of the proposed scheme.

Handwritten Indian numerals recognition system using probabilistic neural networks

Abstract This paper presents a system for the recognition of the handwritten Indian numerals one to nine (1–9) using a probabilistic neural network (PNN) approach. The process involved extracting a feature vector to represent the handwritten digit based on the center of gravity and a set of vectors to the boundary points of the digit object. The feature vector is scale-, translation-, and rotation-invariant. The extracted feature vector is fed to a PNN, which in turn classifies it as one of the nine digits. A set of experiments were conducted to test the performance of the system under different angles between the vectors from the centroid to the boundary of the digit object. A 30° angle results in a 99.72% recognition rate with a short feature vector of 12 entries. This study is meant to be a seed toward building a recognition system for Arabic language characters.

Arm-manipulator coordination for load sharing using compliant control

Arm-manipulator coordination is a new coordination problem in robotics. Human arm-manipulator coordination is superior to both arm-arm coordination and manipulator-manipulator coordination. Likewise, it is expected to have powerful impacts on many applications in the manufacturing, service, and construction industries. This paper introduces this problem and investigates the coordination using a compliant control method. There are several problems in this scheme. First, the stability problem is studied using the Routh-Hurwitz criterion. Then, a very important aspect of the arm-manipulator coordination problem, load sharing, is investigated. Experimental analysis proves the effectiveness of the proposed schemes.

Arm-manipulator coordination for load sharing using reflexive motion control

Arm-manipulator coordination is a new and attractive use of robotic manipulators in unstructured environments. In this paper, we propose a reflexive motion control as a coordination mechanism for the manipulator to share the load with the arm. Reflexive motion is an inspiration of biological systems. The motion is formulated in a manner which assists the manipulator to comprehend the intention of the human arm. It reduces the strain on the arm which is due to the weight of the object. In addition, the speed of manipulation on the object is improved significantly. The effects of the reflexive behavior on stability and load sharing of the system are investigated. Experimental results are presented to prove the effectiveness of the proposed scheme.

Enhanced AODV routing protocol for Bluetooth scatternet

Bluetooth is one of the most widespread technologies for personal area networks that allow portable devices to form multi-hop Bluetooth ad hoc networks, so called scatternets. Routing is one of the challenges in scatternets because of its impact on the performance of the network. It should focus on reducing the power consumption in the network because most of the nodes are battery-operated portable devices. In this paper, we propose a routing protocol for Bluetooth scatternets that customizes the Ad hoc On-Demand Distance Vector (AODV) routing protocol by making it power-aware and suitable for scatternets. It enhances the AODV flooding mechanism by excluding all non-bridge slaves from taking apart in the AODV route discovery process. In addition, it improves the AODV route discovery phase by considering the hop count, the predicated nodes power, and the average traffic intensity for each node as metrics for best route selection. By removing HELLO packets, our protocol reduces the control packets overhead and the power consumption in network devices. Simulation results show that the proposed protocol achieved considerable improvements over other enhanced AODV protocols by increasing the data delivery ratio by 10.78%, reducing the average end-to-end delay by 8.11%, and reducing the average energy consumption by 7.92%.

Intelligent compliant motion control

This paper presents a new work on compliant motion control for position-controlled manipulators. Two new methods for achieving efficient interaction between the manipulator and its environment are developed. In both methods, the compliance is formulated as a function of the interaction force. The first method uses an adaptive element to update the compliance, while the second one adopts a scheme that is believed to be used in human beings to control the stiffness of muscles. The stability of the system is investigated using the small gain theorem. Experiments are conducted in our lab to demonstrate the use of such schemes.

Network Intrusion Detection System using attack behavior classification

Intrusion Detection Systems (IDS) have become a necessity in computer security systems because of the increase in unauthorized accesses and attacks. Intrusion Detection is a major component in computer security systems that can be classified as Host-based Intrusion Detection System (HIDS), which protects a certain host or system and Network-based Intrusion detection system (NIDS), which protects a network of hosts and systems. This paper addresses Probes attacks or reconnaissance attacks, which try to collect any possible relevant information in the network. Network probe attacks have two types: Host Sweep and Port Scan attacks. Host Sweep attacks determine the hosts that exist in the network, while port scan attacks determine the available services that exist in the network. This paper uses an intelligent system to maximize the recognition rate of network attacks by embedding the temporal behavior of the attacks into a TDNN neural network structure. The proposed system consists of five modules: packet capture engine, preprocessor, pattern recognition, classification, and monitoring and alert module. We have tested the system in a real environment where it has shown good capability in detecting attacks. In addition, the system has been tested using DARPA 1998 dataset with 100% recognition rate. In fact, our system can recognize attacks in a constant time.

A biometric-secure e-voting system for election processes

In this paper we propose a multifaceted online e-voting system. The proposed system is capable of handling electronic ballots with multiple scopes at the same time, e.g., presidential, municipal, parliamentary, amongst others. The system caters for integrity of an election process in terms of the functional and non-functional requirements. The functional requirements embedded in the design of the proposed system warrant well-secured identification and authentication processes for the voter through the use of combined simple biometrics. The design of the system guarantees that no votes in favor of a given candidate are lost, due to improper tallying of the voting counts, with the proper incorporation of system FLAGpsilas. Transparency of voting follows through in all phases of an election process to assure the voter that his/her vote went in favor of his/her candidate of choice. Besides its main functional properties, the proposed system is designed to cater for several essential nonfunctional requirements. Of utmost importance are the requirements for correctness, robustness, coherence, consistency, and security. To verify the robustness and reliability of the proposed system, intensive computer simulations were run under varying voting environments, viz. voter density, voter inter-arrival times, introduced acts of malice, etc. Results of the simulations show that security and performance of the system are according to expectations. These results provide the proper grounds that would guide the decision maker in customizing the proposed system to fit his particular voting needs.

New adaptive counter based broadcast using neighborhood information in MANETS

Broadcasting in MANETs is a fundamental data dissemination mechanism, with important applications, e.g., route query process in many routing protocols, address resolution and diffusing information to the whole network. Broadcasting in MANETs has traditionally been based on flooding, which overwhelm the network with large number of rebroadcast packets. Fixed counter-based flooding has been one of the earliest suggested approaches to overcome blindflooding or the “broadcast storm problem”. As the topological characteristics of mobile networks varies instantly, the need of an adapted counter-based broadcast emerge. This research argues that neighbouring information could be used to better estimate the counter-based threshold value at a given node. Additionally results of extensive simulation experiments performed in order to determine the minimum and maximum number of neighbours for a given node is shown. This is done based on locally available information and without requiring any assistance of distance measurements or exact location determination devices.

Image Mosaicing Using Binary Edge Detection Algorithm in a Cloud-Computing Environment

Image Mosaicing is an image processing technique that arises from the need of having a more realistic view of the real world wider than the view captured by the lenses of the available cameras. In this paper, a sequence of images will be mosaiced using binary edge detection algorithm in a cloud-computing environment to improve processing speed and accuracy. The authors have used Platform as a Service PaaS to provide a number of nodes in the cloud to run the computational intensive image processing and stitching algorithms. This increased the processing speed as most of image processing algorithms deal with every single pixel in the image. Message Passing Interface MPI is used for message passing among the compute-nodes in the cloud and a MapReduce technique is used for image distribution and collection, where the root node is used as reducer and the others as mappers. After applying the algorithm on different sequence of images and different machines on JUST cloud, the authors have achieved high mosaicing accuracy, and the execution time has been improved when comparing it with sequential execution on the images.