Advances in Robot Design and Intelligent Control

The use of distributed constraint satisfaction problem for the coordination of holonic schemes that include multi-robot systems is investigated here. The formalism needed to apply the constraint satisfaction approach for manufacturing problems is discussed and exemplified in a case study. An implementing solution is also introduced. The proposed method determines safe operation even in cases with conflicting goals, without using any centralized component.

The paper proposes a method for measuring energy consumption of single phase equipment. Although it can be used on different domains the solution targets the shop floor level of robotized manufacturing systems. The paper focuses thus on the energy consumption of industrial robots for different operation types. This solution is extended in the second part of the paper for a set of workstations cooperating in order to minimize energy consumption at global level for a batch production.

The production and assembly of customized products increases the demand for flexible automation systems. One approach is to remove the safety fences that separate human and industrial robot to combine their skills. This collaboration possesses a certain risk for the human co-worker, leading to numerous safety concepts to protect him. The human needs to be monitored and tracked by a safety system using different sensors. The proposed system consists of a RGBD camera for surveillance of the common working area, an array of optical distance sensors to compensate shadowing effects of the RGBD camera and a laser range finder to detect the co-worker when approaching the work cell. The software for collision detection, path planning, robot control and predicting the behaviour of the co-worker is based on the Robot Operating System (ROS). A first prototype of the work cell shows that with advanced algorithms from the field of mobile robotics a very flexible safety concept can be realized: the robot not simply stops its movement when detecting a collision, but plans and executes an alternative path around the obstacle.

The design process of mechatronic devices is usually performed with Model-Based Design (MBD) methods. This approach enables obtaining properties and functional behaviour of designed devices at lower costs of prototyping. Building prototypes is usually the last operation before the real manufacture of products and includes several experimental tests for parameter verification. As prototype building is the most expensive part of the design process, the Hardware-in-the-loop (HIL) and Software-in-the-loop (SIL) simulation methods are strongly recommended to decrease final production cost of designed devices. This paper deals with designing a specific test bed for performance quality evaluation of compliant robotic devices. The proposed equipment enables parameter verification and evaluation of differences between mathematical models of flexible parts and their real characteristics. Thus, the structures and parameters of the compliant devices of interest can be optimally designed. The paper also discusses the utilization mode of the proposed testing and performance evaluation equipment for a designed micro-gripper.

The paper presents some design aspects concerning robot cooperation methods in order to accomplish dexterous tasks using two industrial robots with different controllers. The goal of this research is to present assembly strategies of two objects using an external master-slave controller for the robots actions. The method described in the paper presents a new solution for automatic robot collaboration and interaction with user interface.

Some examples of the most interesting automatic devices of the Hellenistic Age are presented. These devices can be considered the first examples of automatic mechanical systems, thus representing the precursors of the automation; they clearly show how the concept of automation was present in the minds of ancient scientists and engineers since the II century B.C. or even earlier. The devices also clearly show the surprising modernity of the knowledge of the ancient scientists and engineers, both conceiving the mechanical designs and the building of them. Moreover, the presented device spans a rather wide range of fields of applications. The automatic systems that were chosen are presented by grouping them by inventor. The latter are: Archimedes, Heron of Alexandria, Ctesibius, Dionysius of Alexandria and Philon of Byzantium.

The paper presents a theoretical study about the gripping of an underactuated tendon driver finger. The studies presented in the paper have been performed to analyse the capability of the proposed device to apply forces on the grasped object and to analyse the behaviour of the contact actions during the grasping. The analysis of two models is reported and the results of simulations are shown. The obtained results show a good efficiency of the designed finger.

The paper presents a theoretical study about the dynamic behaviour of an underactuated finger. By modelling the equation of dynamics, two kinds of fingers were studied: the first with equal phalanges, and the second with three different phalanges whose parameters are similar to those of a human finger. The results obtained for this last type of configuration are presented in the paper. The studies reported in the paper have been realized to study the dynamic behaviour of the underactuated finger; the main scope was to investigate the geometrical parameters which allow obtaining a more suitable closing sequence of the phalanges in order to better grasp objects.

The aim of this paper is to propose a swivel walker design with electromotor module supporting the movement of handicapped people and determining the limit positions of the equipment. In the first part the paper describes the functional principle and design issues of the equipment. Initially, the design of the equipment was full mechanical, such devices being still used. The movement with mechanical swivel walker is physically demanding and for this reason we proposed a swivel walker design with electromotor modules to facilitate the movement of handicapped people. In its second part, the paper describes the stability principle of two legged equipment and determines the height CoG position limit to ensure swivel walker stability.

The identification of a model able to relate the deformation of Shape Memory Alloy (SMA) wire to a state variable easily measured is widely studied in recent years. The electric resistance (ER) of a SMA wire varies depending on its martensite and austenite fraction, so the determination of the biunivocal relationship between the wire shortening and its electric resistance allows “previewing” the position of the SMA wire. In this way the resistance of the SMA wire can be used as feedback variable in a control system. A test bench was first used to determine the above mentioned relationship, and then this relation is used in a fuzzy control system to impose a desired position to a SMA wire and to check the response of the device. This type of control doesn’t need a position sensor, which is a certain advantage in terms of cost, overall dimensions and weight for possible applications. The performances of this position control with resistance feedback are good and adequate for many applications; in particular it will be suitable for all applications which do not dispose of space to place a position sensor—like in aerospace applications or micro manufacturing.

The growing use of robots in automated industrial processes involves the development of the solutions adopted for grasping objects. These devices or grippers are used for handling components and products that can have different shapes, materials and dimensions. Current demand for more cost-effective and flexible industrial processes requires smart grippers able to perform a variety of functions. In this paper we present a comparison of different architecture solutions for an industrial gripper with specific features. Using a 3-Jaw gripper model, we consider two different ways to grasp the object. In particular we introduce all requirements of the gripper, the process design for reaching the target of the project using a modular approach and the possible architectures of gripper.

The article describes an experimental evaluation of performance of a flexible actuator specially conceived for propulsion of biomorphic robots. Static and dynamic characteristics are presented, particularly referring to the energy consumption.

The work presented in this paper reports a research done in order to optimize the relation speed—trajectory length for a complex robotic assembly task. The assembly task consists in fixing an engine part with 8 screws, the screws being already inserted and pre-fixed but not tightened; in some cases the screws must be screwed for a length of 1 cm, and then tightened at 25 Nm. The operation duration (cycle time) should be of maximum 45 s measured from the time the pallet enters in the working area until the pallet exits the working area. Due to the conveyor operation which takes 12 s to place the pallet in the working position and to remove the pallet from the working area, only 33 s remain for the robot operation including the operation time of the screwdriver placed on the robot. The solution is based on developing an algorithm that uses the dynamics equations of the robot to compute the time needed to accomplish the task, based on the load of the robot and the stop points on the trajectory.

The traditional ways of solving various tasks “optimally” in control technology and robotics normally are based on the minimization of some cost function (or functional). On the basis of function minimization various “generalized inverse matrices” can be introduced that have special significance in the inverse kinematic tasks of redundant manipulators, where the possible solutions are ambiguous—therefore various choices are available. The solution suggested here tackles the question of optimality by the geometric interpretation of the simple and computationally efficient Gram-Schmidt algorithm. The method is presented via simulations using a redundant arm structure.

This paper presents a control strategy for a swarm of mobile/flying robots operated in 3D space. The described biologically inspired method was developed to solve exploration or monitoring tasks. We discuss a possibility to extend an algorithm [

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] to 3D space in this paper. The presented model is a decentralized adaptive system with shared memory representing the environment.

Omni-directional mobile robots are very attractive because they have a very good mobility, which make them appropriate when they have to move in tight areas, avoid obstacles, and find the way to the next location. To move with precision in such environments, the accurate estimation of the position is very important. The authors provide in this paper information about the design of an omni-directional robot and its control system. Also, preliminary ideas about the design of an odometer are presented.

In this paper we derive analytical expressions which describe the law of change of generalized coordinates of an exoskeleton, such that the mechanism performs standing up motion. Using the obtained expressions the control system has been designed and the controller’s coefficients have been tuned. The behaviour of the control system with additional linear element was studied. The modified system shows significant improvement, as compared to the initial one.

The article presents a mathematical model of motion of a robotic system that moves in jumps from the surface using the on-board catapult and selected stages of the jump. Conditions switch between stages are formulated, special attention being paid to the slideway design. A comparative analysis of the results obtained in the numerical simulation methods and the data collected from real experiments is presented.

Model predictive control (MPC) is a very attractive control algorithm used to solve the complex problems of image-based visual servoing (IBVS) systems. Many image-based predictive controllers were reported, each being different regarding the implementing of the MPC concept. In this paper, we present a MPC framework for IBVS applications, the main contributions being a new visual predictor and the introduction of the reference trajectory.

The paper presents a comparative analysis of current methods for capturing human hand gestures and using then the results in virtual reality environments as a mean of direct, non-intrusive interaction between human and computer. Compared to the methods which are using different data gloves, the Motion Leap device enables new ways of interactions that are not intrusive. In this paper a system is developed that uses Motion Leap to capture human hand poses and recognize gestures, the results of the analysis being sent to a virtual reality environment for further, task-oriented high level processing.

In this paper we present considerations for implementing and using robot vision in glass production. We concentrate specifically on the forming processes of those shell glass objects that are still produced with a considerable amount of manual labour. It is shown that every practical robot automation solution in these production phases must include the perception of the glass object’s shape, implemented with computer vision. A number of particular requirements and conditions are identified, originating from high and ever changing temperature and from specific production environment conditions.

Mobile robots are extensively approached as investigation topic in various research laboratories, due to their diverse applications. Currently, the interest is focused toward applications of mobile robots within unstructured working environments. The successful running of this type of applications is subject to the possibility of localizing obstacles within the working environment. This paper deals with a method to determine the position and the orientation of a rectangular object with respect to several infrared sensorial elements. Locating an object expects the determination of the reference frame coordinates of this object and of the object orientation relative to the axes of a coordinate system.

Our research aims to develop a new personalized social interaction model between a humanoid robot and an individual suffering of Autistic Spectrum Disorder (ASD), so as to enhance his/her social and communication skills. In order to define individual’s profile, we posit that the individual’s reliance to proprioceptive and kinematic visual cues will affect the way an individual suffering of ASD interacts with a social agent. We describe a first experiment that defines each participant’s perceptivocognitive and sensorimotor profile with respect to the integration of visual inputs, thanks to the Sensory Profile questionnaire and an experimental set-up. We succeeded to form 3 groups with significant different behavioural responses inside our subject pool formed by 7 adults and 6 children with ASD. In a second experiment, we presented the Nao robot to all of our participants. We video-analysed their behaviours and compared them to the profiles we defined. In view of our results, this first interaction confirmed our hypothesis: participants with a weak proprioceptive integration and strong visual dependency had more successful interaction than participants with an overreliance on proprioceptive input and hyporeactivity to visual cues.

In this paper, the human-robot collaboration for executing complicated handling tasks for folding non-rigid objects is investigated. A hierarchical control system is developed for the co-manipulation task of folding sheets like fabrics/cloths. The system is based on force and RGB-D feedback in both higher and lower control levels of the process. In the higher level, the perception of the human’s intention is used for deciding the robot’s action; in the lower level the robot reacts to the force/RGB-D feedback to follow human guidance. The proposed approach is tested in folding a rectangular piece of fabric. Experiments showed that the developed robotic system is able to track the human’s movement in order to help her/him to accomplish the folding co-manipulation task.

This paper describes a specific perspective on developing case studies related to education in robotics. The proposed framework intends to support students learning how to develop distributed software applications through functionality composition. The multi-agent approach is used as a test bed for case studies development. It tries to stress the role of the application development platform in creating rich simulations, giving students the possibility to express their goals with clarity, and creating suitable application architectures to achieve their goals. The presented roadmap describes three “Technology to Teach Technology” platforms that support distributed application development. The last section of the paper gives the structure of a specific case study in mobile robotics, along with the Presage2 multi-agent platform.

This paper presents a framework for multimodal human-robot interaction. The proposed framework is intended to bring important contributions to the development of human robot interaction to facilitate intuitive programming and to enable easily adapting to changes in robot task without the need of using skilled personnel. The key elements of this system are speech and hand gesture recognition, text programming, and interaction capabilities that allow the user to take over the control of the robot at any given time. Furthermore, our approach is focused on robot tasks. A user can express his/her preference for one or more modalities of interaction so that selected modalities fit user’s personal needs.

In this paper the authors present a robot leg used to form a hexapod mobile robot structure. For the leg in question the direct kinematics, inverse kinematics and dynamic model were derived. The dynamic model was implemented using SimMechanics toolbox from Matlab. The trajectory for the leg tip was implemented using piecewise cubic spline interpolation. The algorithms and models were developed and simulated using the Matlab software suite.

The role of the robot actuator is transferring execution power in prescribed manner for a desired motion, so that a working mechanism can realize required positioning (in handling or technological operations) with specified accuracy and speed. A suitable choice of the actuator depends not only on its mechanical parameters, but also on sensing and control. Performance data of actuators from various manufacturers are comparable, the difference between them being mostly due to their design. The reported research is part of a project in which it was necessary to design and implement accurate reducers and actuators in various modular kinematic solutions. These modules should be possibly stacked in desired shapes, allowing them to be deployed in production machines and robotic equipment according to specific customer requirements, such as technological heads. The paper describes the design and FEM analysis of technological heads for 2-axis handling and robotic systems.

This paper presents a new hyper-redundant robotic arm structure and its sensorial, driving and control systems. A system of cables actuated by DC motors is used for bending. The position of the robot can be obtained by bending it with the cables and by blocking the position of the needed elements using an electro pneumatic system. The major advantage of this type of actuator consists in the fact that the robot can be moved using a boundary control by cables with a single actuating unit, the position blocking system for any element being relatively simple. The main features and advantages of the sensorial system and global robot system are presented. The dynamic model of the arm is developed using Lagrange’s formalism; the motion control system is based on the adaptive computed-torque method. Finally, experimental results are described.

In this study, the dynamic model of a tentacle robot in two-dimensional space will be presented. We shall attempt to achieve the discretization of this type of robot, and then, by applying a nonlinear observer, the driving control system of the hyper redundant arm will be achieved. Some results obtained by simulating the robot’s motion will be presented and compared.

In this paper, 3D printing is presented as useful means for checking design feasibility of mechanism structures for robots. A procedure is outlined for rapid prototyping that can produce scaled prototypes for experimental validation since early stages of robot developments. An example from LARM activities shows the soundness and practical implementation of the proposed method.

The present study uses MATLAB as a tool to develop and to solve the dynamical equations of motion for an open kinematic chain. MATLAB is convenient for finding the equations of motion using Lagrange method and for solving numerically the nonlinear differential equations.

Needle insertion procedures cover a large area of applications, like brachytherapy (BT), biopsy or fluid extraction. The paper presents the kinematics of a novel parallel robot designed for needle placement procedures. This implies that the needle will be inserted in the patient’s body from the outside up to a target point following a linear trajectory, the needle tracking being achieved using: visual feedback, ultrasound if possible, otherwise computer tomography (CT). The structural synthesis, the robot kinematics, its workspace and some simulation results are presented in the paper.

Robotic systems used for prostate biopsy offer important advantages compared to the manual procedures. In the robotic assisted prostate biopsy procedure, an important problem is to identify the optimal needle trajectories that allow reaching the target tissue and avoiding vital anatomical organs (major blood vessels, internal organs etc.). The paper presents an algorithm for optimal planning of the biopsy needle trajectories, based on virtual reality technologies, using as case study a novel parallel robot designed for transperineal prostate biopsy. The developed algorithm has been tested in a virtual environment for the prostate biopsy robotic-assisted procedure and results are presented.

This paper proposes a robot design which combines an unobtrusive presence around the household with a patient rehabilitation tool. The robot is envisaged to spend most of its time in standby mode, springing into action at pre-set times in order to engage the patient into taking a rehabilitation program. The rehabilitation tool guides the patient through a set series of prescribed repetitive physical exercises, provides feedback and keeps track of the patient’s progress, and finally summarises the feedback to a clinician who can supervise exercise uptake and effectiveness. We have achieved proof of this concept on two separate fronts which have been tested separately: an obstacle-avoidance robot which finds (and composes photographs of) people, and a stand-alone piece of software which displays and assesses physiotherapy exercises.

In immobilized patients like paraplegic subjects, due to absence of leg muscle contraction, venous return to the heart is reduced and this may induce important diseases to the cardio-circulatory system. The application to legs of a mechanical stimulation operated by an Intermittent Pneumatic Compression (IPC) device in replacing striate muscle pump on limb veins may recover venous return to the heart, thus restoring correct cardio-circulatory performance. This paper deals with the study of an effective way to control such a device. Based on the numerical simulation of the human-machine system, the paper investigates and proposes an effective control solution.

The tracking system monitors and recognizes several potential objects of interest. An operator selects an object for tracking. During the tracking mode the decision is made to initiate the procedure of aiming. Three measurements of the distance are used to establish motion parameters of the tracked object. The trajectory of the motion is calculated in order to specify the future hit point position. Finally, servos drive the system into the ballistic aiming position. To increase the hit probability, the whole tracking and aiming procedure is repeated automatically.

This paper addresses some alternatives to classical trajectory generation for an unmanned aerial vehicle (UAV) which needs to pass through (or near) a priori given way-points. Using differential flatness for trajectory generation and B-splines for the flat output parameterization, the current study concentrates on flat descriptions which respect to UAV dynamics and verify way-point constraints.

The paper addresses the localization issue for skid-steer vehicles. The large extent of slippage incurred by this type of vehicle in a turn heavily degrades the accuracy of their position estimation systems. Based on the kinematics modelling of skid-steering, the concept of equivalent track is presented. During field experiments with an off-road unmanned vehicle, this new concept proved to be effective in reducing localization errors up to two orders of magnitude.

The adoption of wireless sensor network systems is becoming wide-spread in critical large-scale monitoring applications. These include but are not limited to pipeline infrastructures for oil and water, border areas, roads and railway systems. In such scenarios, airborne robotic platforms like unmanned aerial vehicles (UAVs) can provide valuable services for data collection, communication relaying and higher level supervision. This is the case for both single UAV deployment as well as for swarms of UAVs collaboratively integrated into monitoring systems. The paper discusses the opportunity for in-network pre-processing of sensor data for local UAV task planning in order to increase the efficiency of data collection processes. A gradient scheme is introduced for decision support of the UAV task planning. Results are validated by simulation.

One of the well-known topics in wireless sensor networks (WSNs) is energy consumption efficiency in regard to communication needs. An unmanned aerial vehicle (UAV) that gathers data from a ground WSN can be seen as a gateway for the WSN. The paper presents a solution for improving the communication efficiency of a hybrid UAV-WSN system by using directional antenna and synchronization mechanisms. The final goal is to increase the life of the ground nodes. The targeted architecture is described and some modelling assumptions are discussed.

The problem of top viewing human tracking in a closed environment, such as is the area of a shopping centre is a challenging one. In this paper we test a number of Kalman and simple particles filters-based algorithms for solving the visual tracking problem. Although results obtained from the experiments that we have conducted are promising and can be considered as adequate from all practical perspectives, more research must be done so that the filter used takes into account the existing peculiarities in the movements of human beings.

This paper considers the combinatorial problem of motion planning and scheduling with stochastic demands. Here, an autonomous vehicle with limited capacity is requested to serve workstations in an industrial environment. Its workstation has a stochastic demand which is revealed upon the arrival of the vehicle. This combined problem is solved by optimizing the vehicle’s schedule and route (minimum travel distance) under collision-free and vehicle-capacity constraints. An optimization strategy based on the combination of a genetic and micro-genetic algorithm is developed in order to determine the optimum solution. Experimental results demonstrate the effectiveness of the proposed approach.

The paper addresses the problem of learning internal task-specific dynamic models for a reaching task. Using task-specific dynamic models is crucial for achieving both high tracking accuracy and compliant behaviour, which improves safety concerns while working in unstructured environment or with humans. The proposed approach uses programming by demonstration to learn new task-related movements encoded as Compliant Movement Primitives (CMPs). CMPs are a combination of position trajectories encoded in a form of Dynamic Movement Primitives (DMPs) and corresponding task-specific Torque Primitives (TPs) encoded as a linear combination of kernel functions. Unlike the DMPs, TPs cannot be directly acquired from user demonstrations. Inspired by the human sensorimotor learning ability we propose a novel method which autonomously learns task-specific TPs, based on a given kinematic trajectory in DMPs.

In this paper we propose a method of adapting motion to the environment based on force feedback. Our method combines two approaches of motor primitive adaptation. Starting from a single demonstration of motion, we use iterative learning control to adapt the motion to different conditions of the environment, for example, the height of the table. The adaptation is realized through coupling terms at the velocity level of a dynamic movement primitive, and acts as a feedforward component, predetermined for the given external condition. As adaptation to each condition takes several iterations, we combine this method with statistical generalization, employing Gaussian process regression. By generating a small database of coupling terms through iterative learning, we adapt to the environment by generalizing between the coupling terms in the database, thus either already achieving an appropriate coupling term for our demonstration trajectory or providing an initial estimate for the adaptation. Consequently, the learning doesn’t need to be executed for every condition of the environment, but only for a small set. In the paper we provide the details of the method and evaluate it in a simulated setting for the use case of placing a glass on a table.

In the domain of mobile robots local maps of environments are used as knowledge base for decisions allowing reactive control in order to prevent collisions when following a global trajectory. These maps are normally discrete and updated at relatively high frequency, but with no dynamic information. The proposed framework uses a sparse description of clustered scan points from a laser range scanner. These features and the system odometry are used to predict the agent’s ego motion as well as feature motion using an Extended Kalman Filter. This approach is similar to the Simultaneous Localization and Mapping (SLAM) algorithm but with low-constraint features. The presented local Simultaneous Localization and Mapping (LSLAM) approach creates a decision base, holding a dynamic description which relaxes the requirement of high update rates. Simulated results demonstrate environment classification and tracking as well as self-pose correction in static and in dynamic environments.

This paper presents the authors’ contribution in designing and evaluating a transmission system for a robotic wheelchair. The kinematics of the proposed transmission is analysed in order to realize a proper gear synthesis. A 3D model of the transmission and wheelchair are designed in Solid Works, being then used for the dynamic simulation of the system in Adams software. The wheelchair motion simulation is done in Adams in two modes: traction motion and steering motion active. In case of traction motion simulation the resulting trajectory is a straight line displacement, whereas in the case of active steering motion the resulting displacement trajectory is circular. Simulation results demonstrate the efficiency of the developed transmission model and assure successful implementation of this design in a robotic wheelchair.

The paper addresses the mechanical design of a river underwater robot (remotely operated vehicle—ROV) suitable for implementation in delicate and risky underwater tasks. The main factors that determine the mechanical design of the robot are hydrodynamic drags and low underwater visibility. The robot body is inspired by biological models of fishes as well as by the “golden ratio”-a natural geometry proportion that commonly appears in nature. The underwater ROV presented in the paper has two redundant, poly-articular, tendon-driven robot arms, suitable for use in submarine tasks due to their flexibility and light mechanical structure. The paper explains how robot propulsion is determined and which kind of thruster motors are chosen for this purpose. The designed mechanical structure is evaluated by corresponding simulation tests and the results of which are analysed. The paper finally presents concluding remarks and objectives of future work.