Purpose Assistive technology products are designed to provide additional accessibility to individuals who have physical or cognitive difficulties, impairments and disabilities. The purpose of this paper is to deal with the control of a knee joint orthosis intended to be used for rehabilitation and assistive purpose; this control aims to reduce the influence of the uncertainties and eliminating the external disturbances in the system. Design/methodology/approach This paper deals with the robust adaptive sliding mode controller (ASMC) of human-driven knee joint orthosis system with mismatched uncertainties and external disturbances. The shank-orthosis system has been modeled and its parameters have been identified. This control reduces the effect of parameter uncertainties and external disturbances on the system performance and improves the system robustness as results. The ASMC was designed to offer the possibility to track the state of the reference model. Moreover, the Lyapunov stability theory was used to study the asymptotical stability of the ASMC. Findings The advantage of the robust ASMC method is the tracking precision and reducing the required time for eliminating external disturbances and uncertainties. The experimental results show in real-time in terms of stability and present that the advantages of this control approach are the position tracking and robustness. Originality/value In this paper, to deal with the parameter uncertainties of the human-driven knee joint orthosis, an ASMC was successfully applied based on sliding mode and Lyapunov stability theory. It has good dynamic response and tracking performance. Besides, the adaptive algorithm is simple, easy to achieve and has good adaptability and robustness against the parameter variations and external disturbances. The design technique is simple and efficient. The development of this control takes into consideration the perturbation, allowing to track a desired trajectory.
Purpose The following paper is a “Q&A interview” conducted by Joanne Pransky of Industrial Robot Journal as a method to impart the combined technological, business and personal experience of a prominent, robotic industry engineer-turned successful innovator and leader, regarding the challenges of bringing technological discoveries to fruition. This paper aims to discuss these issues. Design/methodology/approach The interviewee is Mel Torrie, CEO and President of Autonomous Solutions, Inc. (ASI). ASI manufactures an OEM/vendor independent software and hardware solution retrofitted to existing equipment to create a wide variety of fully autonomous vehicles spanning agriculture, mining, automotive, industrial cleaning, security and government/military applications. In this interview, Torrie shares how he first got started in the robotics field along with his experiences in running his ground-breaking startup. Findings In 1999, Torrie received a Master’s Degree in Electrical Engineering at Utah State University (USU) where he worked on two National Aeronautics and Space Administration (NASA) space shuttle payloads. After his work at USU, he managed robotics development programs for John Deere, the US Department of Defense and the US Department of Energy. He founded ASI, a spin-off of the Center of Self Organizing and Intelligent Systems (CSOIS) at USU, in 2000. Originality/value Torrie was a pioneer and visionary who bootstrapped ASI from the beginning. Under Torrie’s leadership, ASI raised over $85m in a unique business model where there is no equity but only strategic partners. These foremost companies are given exclusive rights to their vertical market and jointly own their industry’s driverless vehicle’s intellectual property (IP) with ASI. The vehicles are developed and tested at ASI’s 100-acre proving ground facility in Utah. To date, ASI’s more than 100 employees and their business partners have automated 75 different vehicle types and ASI continues to create new markets. Some of ASI’s notable installations include the Bingham Canyon Mine clean-up effort; BatCat, the teleoperated CAT telehandler for the Los Angeles Police Department; and the robotic durability testing program with Ford Motors, Toyota, Fiat Chrysler Automotive, Hyundai, General Motors as well as other private proving grounds.
Purpose The purpose of this study is to design a robotic inline measurement system for spot welding quality control to achieve process requirement without any operator during the manufacturing flow. Design/methodology/approach A robot manipulator carries a stereo-camera and an ultrasonic control probe. The center position of the spot welding point is determined by evaluating the results of the edge, gradient and symmetry approaches from the methods proposed up to now in the literature to increase reliability. The center position of the spot welding point, determined in the camera reference plane, is transferred to the robot base plane coordinates with the hand–eye calibration proposed in this manuscript. Weld quality is checked by the ultrasonic test probe located at the spot welding point. Findings While operators can only control welding quality, the developed station can also evaluate the quality based on geometric accuracy by processing the deviation of the position of the spot welding points. The proposed calibration method and the results of other methods in the literature are presented in this study by comparing it with synthetic data in simulations and in practical application. Research limitations/implications The quality control is performed not only for the spot welding made with robots but also for the manual welds as well. Because of vision configuration, and reliability issues, maximum allowable offset by the correct spot position is limited to 20 mm to position the manipulator for testing. The installation and pretest works of the developed robotic welding quality control station are completed in the Body Shop Area of Ford Otosan factory in Kocaeli/Turkey. The results of the robotic control process are monitored by the quality assurance team. Integration of automation with the production line will be completed and an inline measurement will be done. Originality value In this paper, a new hand–eye calibration method based on simple and closed-form analytical solutions has been presented. The objective function is defined as reducing the deviation in the point projection, rather than reducing the error in the calibration equation. To increase reliability, combining the results of existing centering algorithms for the detection of the strongly deformed spot welding spot center, although it is normally in a circular form, has been suggested.
Purpose This paper aims to address the question posed in the title by considering the present uses and potential future role of robots in the construction industry. Design/methodology/approach Following a short introduction, this first considers developments involving the robotic automation of conventional building practices, notably bricklaying and glazing. This is followed by a discussion of the role of drones and developments in autonomous ground vehicles. It then provides examples of the rapidly growing use of robotic 3D printing of concrete structures and concludes with a discussion. Findings Many different classes of robots aimed at a diversity of uses in the construction industry exist or are at an advanced stage of development. While some seek to automate conventional building practices, others such as concrete printing robots underpin novel construction concepts. Their use has the potential to yield significant economic, operational, environmental and other benefits and many technologically advanced companies have recently been established which aim to exploit these opportunities. While the industry has traditionally been slow to adopt new technologies, robots are now exerting a real impact and will inevitably play a vital and growing role in the future. Originality/value The construction industry is under pressure to modernise and improve its efficiency, and this article illustrates the role that robots are playing in this process.
Purpose This paper aims to introduce a simple hand-eye calibration method that can be easily applied with different objective functions. Design/methodology/approach The hand-eye calibration is solved by using the closed form absolute orientation equations. Instead of processing all samples together, the proposed method goes through all minimal solution sets. Final result is chosen after evaluating the solution set for arbitrary objectives. In this stage, outliers can be excluded optionally if more accuracy is desired. Findings The proposed method is very flexible and gives more accurate and convenient results than the existing solutions. The mathematical error expression defined by the calibration equations may not be valid in practice, where especially systematic distortions are present. It is shown in the simulations that the solution which results the least mathematical error in systems may have incorrect, incompatible results in the presence of practical demands. Research limitations/implications The performance of the calibration performed with the proposed method is compared with the reference methods in the literature. When the back-projection error is benchmarked, which corresponds to the point repeatability, the proposed approach is considered as the most successful method among all others. Due to its robustness, it is decided to make tooling-sensor calibrations by the recommended method, in the robotic non-destructive testing station in Ford-OTOSAN Kocaeli Plant Body Shop Department. Originality/value Arranging the well-known AX = XB calibration equation in quaternion representation as Q_A = Q_x × Q_B × Q_x reveals another common spatial rotation equation. In this way, absolute orientation solution satisfies the hand-eye calibration equations. The proposed solution is not presented in the literature as a standalone hand-eye calibration method, although some researchers drop a hint to the relative formulations.
Purpose - The purpose of the study is to design a three-dimensional (3D) triglide parallel robot with a different approach and to control the manufactured robot via sliding mode control method that has not been applied to the robot before. Design/methodology/approach - The x,y and z coordinates of the end effector of the robot have been given as a reference. The x, y and z reference values are transformed as new reference values of the vertical movement of the robot on the endless screw by using the inverse kinematic equations of the robot. The control of the robot over these reference values is provided by a sliding mode control. The MATLAB/real-time toolbox has been used for creating the interface. The real-time control of the triglide robot has been carried out with a sliding mode controller in the Simulink environment. Findings - When the results of the sliding mode control are examined, it is seen that the desired reference values are provided in about 0.6 s. The velocity of the sliding limbs in each arm of the robot is approximately 50 mm/s. The reference values have been reached using the sliding mode control method, with an average error of 0.01 mm. In addition, the problem of chattering in the system caused by using the sign function has been relatively eliminated by using the saturation function instead of the sign function. Thus, the sliding mode control method with saturation function is more feasible. Originality/value - In this study, the triglide parallel robot was manufactured using a 3D model after taking into consideration the dimensions of the 3D model. After production, the necessary hardware connections were provided, and a real-time sliding mode control method was implemented to the robot by using the interface program in MATLAB/ Simulink environment. The literature contribution of the paper is the real-time control of the triglide robot with the sliding mode control method.
Purpose - The purpose of this paper is to reduce the strain and vibration during robotic machining. Design/methodology/approach - An intelligent approach based on particle swarm optimization (PSO) and adaptive iteration algorithms is proposed to optimize the PD control parameters in accordance with robotic machining state. Findings - The proposed intelligent approach can significantly reduce robotic machining strain and vibration. Originality value - The relationship between robotic machining parameters is studied and the dynamics model of robotic machining is established. In view of the complexity of robotic machining process, the PSO and adaptive iteration algorithms are used to optimize the PD control parameters in accordance with robotic machining state. The PSO is used to optimize the PD control parameters during stable-machining state, and the adaptive iteration algorithm is used to optimize the PD control parameters during cut-into state.
Purpose - This paper aims to present a method for improving the state estimation of a robot in the presence of noise measurement, which can improve the performance of the robot controller. Design/methodology/approach - In this work, a novel nonlinear tracking differentiator (NTD) was formulated to solve the problems of phase lag, low stability and amplitude attenuation faced by traditional tracking differentiators, which can be used for the state estimation of a robot. Based on the user-defined function stu() with linear and nonlinear characteristics, the authors establish a new acceleration function of NTD and confirm its global asymptotic stability by using the Lyapunov method and the system equivalence method. Phase plane analysis shows that the origin is its stable nodal point or focus point and uncovers the basic constraint conditions for parameter regulation. In addition, the convergence property and robustness performance against noises are studied by describing function method. Findings - Comparative simulations, robot state estimation experiments and joint trajectory tracking experiments have indicated that NTD proposed integrates tracking rapidness, accuracy and transitional stability and has high approximation and filtering effects on generalized derivatives of the signal, which contribute to an excellent performance of robot controller in stability and response speed in practice. Originality/value - The main contribution of this paper lies in the design of a novel NTD, which successfully improves the state estimation of a robot joint in noisy surroundings, the tracking performance of robot controller and the stability of the system.
Purpose This paper aims to provide details of the safety considerations, technologies and standards associated with robots that interact with, or operate in proximity to, humans. Design/methodology/approach Following an introduction, this paper first considers collaborative robots and discusses their safety features and the new technical specification ISO/TS 15066, together with certain allied safety standards. It then discusses ISO 13482 and a range of assistive, personal care and service robots which comply with this and highlights new standards that are under development. Mobile warehouse and delivery robots are then considered, together with the safety technologies used and the associated standards. Finally, brief concluding comments are drawn. Findings The recent proliferation of robots that interact with humans or operate in proximity to them has led to the development of standards and specifications which seek to ensure safe operation. These allow robot manufacturers to design inherently safe products that will gain market acceptance and also help to inspire confidence among users. A number of new standards and specifications have been proposed or are being developed, and this trend is set to continue as new classes of robotic products emerge. Originality/value All manner of robots are being developed which interact with humans, and this provides details of the associated safety considerations, technologies and standards.
Purpose The purpose of this paper was to present a soft landing control strategy for a biped robot to avoid and absorb the impulsive reaction forces (which weakens walking stability) caused by the landing impact between the swing foot and the ground. Design/methodology/approach First, a suitable trajectory of the swing foot is preplanned to avoid the impulsive reaction forces in the walking direction. Second, the impulsive reaction forces of the landing impact are suppressed by the on-line trajectory modification based on the extended time-domain passivity control with admittance causality that has the reaction forces as inputs and the decomposed swing foot’s positions to trim off the forces as the outputs. Findings The experiment data and results are described and analyzed, showing that the proposed soft landing control strategy can suppress the impulsive forces and improve walking stability. Originality/value The main contribution is that a soft landing control strategy for a biped robot was proposed to deal with the impulsive reaction forces generated by the landing impact, which enhances walking stability.
Purpose - The following paper is a "Q&A interview" conducted by Joanne Pransky of Industrial Robot Journal as a method to impart the combined technological, business and personal experience of a prominent, robotic industry PhD-turned-entrepreneur regarding the commercialization and challenges of bringing a technological invention to market. This paper aims to discuss these issues.Design/methodology/approach - The interviewee is Dr Jun Ho Oh, Professor of Mechanical Engineering at the Korea Advanced Institute of Science and Technology (KAIST) and Director of KAIST's Hubolab. Determined to build a humanoid robot in the early 2000s to compete with Japan's humanoids, Dr Oh and KAIST created the KHR1. This research led to seven more advanced versions of a biped humanoid robot and the founding of the Robot for Artificial Intelligence and Boundless Walking (Rainbow) Co., a professional technological mechatronics company. In this interview, Dr Oh shares the history and success of Korea's humanoid robot research.Findings - Dr Oh received his BSc in 1977 and MSc in Mechanical Engineering in 1979 from Yonsei University. Oh worked as a Researcher for the Korea Atomic Energy Research Institute before receiving his PhD from the University of California (UC) Berkeley in mechanical engineering in 1985. After his PhD, Oh remained at UC Berkeley to do Postdoctoral research. Since 1985, Oh has been a Professor of Mechanical Engineering at KAIST. He was a Visiting Professor from 1996 to 1997 at the University of Texas Austin. Oh served as the Vice President of KAIST from 2013-2014. In addition to teaching, Oh applied his expertise in robotics, mechatronics, automatic and real-time control to the commercial development of a series of humanoid robots.Originality/value - Highly self-motivated and always determined, Dr Oh's initial dream of building the first Korean humanoid bipedal robot has led him to become one of the world leaders of humanoid robots. He has contributed widely to the field over the nearly past two decades with the development of five versions of the HUBO robot. Oh led Team KAIST to win the 2015 DARPA Robotics Challenge (DRC) and a grand prize of US$2m with its humanoid robot DRC-HUBO+, beating 23 teams from six countries. Oh serves as a robotics policy consultant for the Korean Ministry of Commerce Industry and Energy. He was awarded the 2016 Changjo Medal for Science and Technology, the 2016 Ho-Am Prize for engineering, and the 2010 KAIST Distinguished Professor award. He is a member of the Korea Academy of Science and Technology.
Purpose The purpose of this paper is to develop a dual peg-in-hole insertion strategy. Dual peg-in-hole insertion is the most common task in manufacturing. Most of the previous work develop the insertion strategy in a two- or three-dimensional space, in which they suppose the initial yaw angle is zero and only concern the roll and pitch angles. However, in some case, the yaw angle could not be ignored due to the pose uncertainty of the peg on the gripper. Therefore, there is a need to design the insertion strategy in a higher-dimensional configuration space. Design/methodology/approach In this paper, the authors handle the insertion problem by converting it into several sub-problems based on the attractive region formed by the constraints. The existence of the attractive region in the high-dimensional configuration space is first discussed. Then, the construction of the high-dimensional attractive region with its sub-attractive region in the low-dimensional space is proposed. Therefore, the robotic insertion strategy can be designed in the subspace to eliminate some uncertainties between the dual pegs and dual holes. Findings Dual peg-in-hole insertion is realized without using of force sensors. The proposed strategy is also used to demonstrate the precision dual peg-in-hole insertion, where the clearance between the dual-peg and dual-hole is about 0.02 mm. Practical implications The sensor-less insertion strategy will not increase the cost of the assembly system and also can be used in the dual peg-in-hole insertion. Originality/value The theoretical and experimental analyses for dual peg-in-hole insertion are proposed without using of force sensor.
Purpose - This paper aims to conduct a comprehensive fault tree analysis (FTA) on the critical components of industrial robots. This analysis is integrated with the reliability block diagram (RBD) approach to investigate the robot system reliability. Design/methodology/approach - For practical implementation, a particular autonomous guided vehicle (AGV) system was first modeled. Then, FTA was adopted to model the causes of failures, enabling the probability of success to be determined. In addition, RBD was used to simplify the complex system of the AGV for reliability evaluation purpose. Findings - Hazard decision tree (HDT) was configured to compute the hazards of each component and the whole AGV robot system. Through this research, a promising technical approach was established, allowing decision-makers to identify the critical components of AGVs along with their crucial hazard phases at the design stage. Originality/value - As complex systems have become global and essential in today's society, their reliable design and determination of their availability have turned into very important tasks for managers and engineers. Industrial robots are examples of these complex systems that are being increasingly used for intelligent transportation, production and distribution of materials in warehouses and automated production lines.
Purpose This paper aims to present a procedure to change the orientation of a grasped object using dexterous manipulation. The manipulation is controlled by teleoperation in a very simple way, with the commands introduced by an operator using a keyboard. Design/methodology/approach The paper shows a teleoperation scheme, hand kinematics and a manipulation strategy to manipulate different objects using the Schunk Dexterous Hand (SDH2). A state machine is used to model the teleoperation actions and the system states. A virtual link is used to include the contact point on the hand kinematics of the SDH2. Findings Experiments were conducted to evaluate the proposed approach with different objects, varying the initial grasp configuration and the sequence of actions commanded by the operator. Originality/value The proposed approach uses a shared telemanipulation schema to perform dexterous manipulation; in this schema, the operator sends high-level commands and a local system uses this information, jointly with tactile measurements and the current status of the system, to generate proper setpoints for the low-level control of the fingers, which may be a commercial close one. The main contribution of this work is the mentioned local system, simple enough for practical applications and robust enough to avoid object falls.
Purpose The following paper is a “Q&A interview” conducted by Joanne Pransky of Industrial Robot Journal as a method to impart the combined technological, business and personal experience of a prominent, robotic industry PhD-turned-entrepreneur regarding the commercialization and challenges of bringing a technological invention to market. The paper aims to discuss these issues. Design/methodology/approach The interviewee is Dr Howie Choset, Chief Technical Officer at the Advanced Robotics for Manufacturing Institute and Professor of Robotics at Carnegie Mellon University (CMU). Motivated by applications in confined spaces, Dr Choset created a comprehensive program in modular, high degree(s) of freedom (DOF) and multirobot systems. This research led Dr Choset to cofound three companies. In this interview, Dr Choset shares some of his personal and business experiences of working in academia and industry. Findings Dr Choset received his Bachelor of Science, Engineering (BSE) degree in computer science and his Bachelor of Science, Economics (BSEcon) degree in business from the University of Pennsylvania in 1990. Dr Choset received his Masters and PhD from Caltech in mechanical engineering and robotics in 1991 and 1996. Since 1996, Dr Choset has been a Professor of Robotics at CMU and Director of the CMU Biorobotics Lab. He is also the Director of CMU’s undergraduate major and minor of Robotics. Along with his students, Choset formed several companies including Medrobotics (2005) for surgical systems; Hebi Robotics (2014) for modular robots; and Bito Robotics (2017) for autonomous guided vehicles. In 2017, Choset co-led the formation of the Advanced Robotics for Manufacturing Institute, which is a $250m national institute advancing both technology development and education for robotics in manufacturing. Choset is a founding editor of the journal Science Robotics and is currently serving on the editorial board of International Journal Robotics Research. Originality/value Motivated by collaborating with his students and colleagues, Dr Choset continues to make fundamental contributions in design, motion planning, path planning and estimation with the goal of bringing the precision of computer science and applied mathematics to the realities and uncertainties of mechanical systems. Choset’s work has been supported by both industry and government. Medrobotics Corp., a medical robotics company based on Choset’s snake robots, has received US Food and Drug Administration (FDA) regulatory clearance for both colorectal and otolaryngology procedures in the USA.
Purpose - The global performance of industrial robots partly depends on the properties of drive system consisting of motor inertia, gearbox inertia, etc. This paper aims to deal with the problem of optimization of global dynamic performance for robotic drive system selected from available components. Design/methodology/approach - Considering the performance specifications of drive system, an optimization model whose objective function is composed of working efficiency and natural frequency of robots is proposed. Meanwhile, constraints including the rated and peak torque of motor, lifetime of gearbox and light-weight were taken into account. Furthermore, the mapping relationship between discrete optimal design variables and component properties of drive system were presented. The optimization problem with mixed integer variables was solved by a mixed integer-laplace crossover power mutation algorithm. Findings - The optimization results show that our optimization model and methods are applicable, and the performances are also greatly promoted without sacrificing any constraints of drive system. Besides, the model fits the overall performance well with respect to light- weight ratio, safety, cost reduction and others. Practical implications - The proposed drive system optimization method has been used for a 4-DOF palletizing robot, which has been largely manufactured in a factory. Originality/value - This paper focuses on how the simulation-based optimization can be used for the purpose of generating trade-offs between cost, performance and lifetime when designing robotic drive system. An applicable optimization model and method are proposed to handle the dynamic performance optimization problem of a drive system for industrial robot.
Purpose This paper aims to develop a robot for tightening charged bolt to solve the shortcomings of high labor intensity, low efficiency, high risk and poor reliability in artificially tightening drainage board bolt of strain clamp for high voltage transmission line. Realizing bolt-nut capture and location by manipulator is a critical process to complete the whole working task. To solve such key technology, an autonomous location control method for N-joint robot manipulator based on kinematics was proposed. Design/methodology/approach Through D-H kinematics analysis under flexible working environment of transmission line, the autonomous location control of double manipulators can be abstracted as a nonlinear approximation problem based on joint inverse kinematics. In addition, regarding the complex coupling relationship among different joint angles and the complex decoupling process which leads to the non-uniqueness of inverse solution, an improved backpropagation (BP) network was proposed based on the combination of dynamic adaptive adjustment of learning rate and variable momentum factor, so that the inverse kinematics of manipulator can be solved and the optimization evaluation mechanism of inverse solution can be presented. The proposed autonomous location control method is of adaptability to flexible environment and structural parameters of different drainage boards. The simulation results verified the effectiveness of the proposed method. Compared with the other location control, this method can achieve faster location speed, higher precision and lower hardware cost. Finally, the field operation test further validated that such autonomous location control method was of strong engineering practicability. Findings The proposed autonomous location control method is adaptable to a flexible environment and to the structural parameters of different types of drainage board. Simulation results confirm the effectiveness of the proposed method, which, in comparison with other approaches to location control, can achieve faster location, higher precision and lower hardware cost. Finally, a field test further confirms the engineering practicability of the proposed autonomous location control method. Originality/value The proposed method can achieve faster location speed, higher precision which meet the requirement of real-time control relative to the standard BP algorithm. Moreover, it is of strong adaptability to flexible environment and structural parameters for different drainage board. Field operation experiment further validated the engineering practicability of the method.
Purpose Articulated robots are widely used in industrial applications owing to their high repeatability accuracy. In terms of new applications such as robot-based inspection systems, the limitation is a lack of pose accuracy. Mostly, robot calibration approaches are used for the improvement of the pose accuracy. Such approaches however require a profound understanding of the determining effects. This paper aims to provide a non-destructive analysis method for the identification and characterisation of non-geometric accuracy effects in relation to the kinematic structure for the purpose of an accuracy enhancement. Design/methodology/approach The analysis is realised by a non-destructive method for rotational, uncoupled robot axes with the use of a 3D lasertracker. For each robot axis, the lasertracker position data for multiple reflectors are merged with the joint angles given by the robot controller. Based on this, the joint characteristics are determined. Furthermore, the influence of the kinematic structure is investigated. Findings This paper analyses the influence of the kinematic structure and non-geometric effects on the pose accuracy of standard articulated robots. The provided method is shown for two different industrial robots and presented effects incorporate tilting of the robot, torsional joint stiffness, hysteresis, influence of counter balance systems, as well as wear and damage. Practical implications Based on these results, an improved robot model for a better match between the mathematical description and the real robot system can be achieved by characterising non-geometric effects. In addition, wear and damages can be identified without a disassembly of the system. Originality/value The presented method for the analysis of non-geometric effects can be used in general for rotational, uncoupled robot axes. Furthermore, the investigated accuracy influencing effects can be taken into account to realise high-accuracy applications.
