Robot Accidents Research Articles

Real-Time Space Trajectory Judgment for Industrial Robots in Welding Tasks

In welding tasks, the repeated positioning precision of robots can generally reach the micron level, but the data of each axis during each operation may vary. There may even be out-of-control situations where the robot does not run according to the set welding trajectory, which may cause the robot and equipment to collide and be damaged. Therefore, a real-time judgment method for the welding robot trajectory is proposed. Firstly, multiple sets of axis data are obtained by running the welding robot, and the phase of the data is aligned by using a proposed algorithm, and then the Kendall correlation coefficient is used to identify and remove weak axis data. Secondly, the mean of multiple sets of axis data with strong correlation is calculated as the standard trajectory, and the trajectory threshold of the robot is set using the μ ± nσ method based on the trajectory deviation judgment sensitivity. Finally, the absolute difference between the real-time axis trajectory and the standard trajectory is used to determine the deviation of the running trajectory. When the deviation reaches the threshold, a forewarning starts. When the deviation exceeds the threshold + σ, the robot is stopped. Take the six-axis welding robot as an example, by collecting the axis data of the robot running multiple times under the same conditions, it is proved that the proposed method can accurately warn the deviation of the running trajectory. The research results have important practical value for the prevention of welding robot accidents in industrial production.

ADVANCED TECHNOLOGICAL APPLICATION AND NEW HAZARDS

Integrating a technology into a business and making it sustainable can be achieved with a good analysis and a systematic workplace organization. In today's world, where everything has become more connected (Internet of Things, industrial internet, etc.), it is more difficult to analyze risks compared to the traditional point of view. Analyzing the risks and ranking them in order of importance is closely related to the proven dangers and risks of these technologies. In the study, advanced technological applications and the risks they bring were determined using expert opinions. Accordingly, technological work accidents, occupational diseases, cyber-attacks, and accidents based on human error were determined as the main criteria. The sub-criteria were determined as automation and robot accidents, occupational diseases of chemical and biological origin, sabotage and attacks on personal data, and misinterpretation of data/shortage of qualified employees. Microsoft Excel was used in the analysis of the application and the results of each analysis were found to be consistent. According to the analysis results, the most important risk in the order of importance of advanced technological applications and the risks they bring was Occupational Diseases (Criterion 2) with 0.4755, and the most weighted sub-criteria in the paired comparisons was Sabotage and Attack Against Personal Data (Sub-Criteria 3) while 0.3518.

Evaluation of Long-Distance Operability in a Command-Based Multi Relay Tele-Operation System Using LoRaWAN for Preventing Mobile Robot Accidents Due to Wireless LAN Disconnection

Evaluation of Long-Distance Operability in a Command-Based Multi Relay Tele-Operation System Using LoRaWAN for Preventing Mobile Robot Accidents Due to Wireless LAN Disconnection

Liability for robots II: an economic analysis

AbstractThis is the second of two companion papers that discuss accidents caused by robots. In the first paper (Guerraet al., 2021), we presented the novel problems posed by robot accidents, and assessed the related legal approaches and institutional opportunities. In this paper, we build on the previous analysis to consider a novel liability regime, which we refer to as ‘manufacturer residual liability’ rule. This makes operators and victims liable for accidents due to their negligence – hence, incentivizing them to act diligently; and makes manufacturers residually liable for non-negligent accidents – hence, incentivizing them to make optimal investments in R&D for robots' safety. In turn, this rule will bring down the price of safer robots, driving unsafe technology out of the market. Thanks to the percolation effect of residual liability, operators will also be incentivized to adopt optimal activity levels in robots' usage.

Liability for robots I: legal challenges

Abstract In robot torts, robots carry out activities that are partially controlled by a human operator. Several legal and economic scholars across the world have argued for the need to rethink legal remedies as we apply them to robot torts. Yet, to date, there exists no general formulation of liability in case of robot accidents, and the proposed solutions differ across jurisdictions. We proceed in our research with a set of two companion papers. In this paper, we present the novel problems posed by robot accidents, and assess the legal challenges and institutional prospects that policymakers face in the regulation of robot torts. In the companion paper, we build on the present analysis and use an economic model to propose a new liability regime which blends negligence-based rules and strict manufacturer liability rules to create optimal incentives for robot torts.

Critical Hazard Factors in the Risk Assessments of Industrial Robots: Causal Analysis and Case Studies.

BackgroundWith the increasing demand for industrial robots and the “noncontact” trend, it is an appropriate point in time to examine whether risk assessments conducted for robot operations are performed effectively to identify and eliminate the risks of injury or harm to operators. This study discusses why robot accidents resulting in harm to operators occur repetitively despite implementing control measures and proposes corrective actions for risk assessments.MethodsThis study collected 369 operator-injured robot accidents in Korea over the last decade and reconstructed them into the mechanism of injury, work being undertaken, and bodily location of the injury. Then, through the techniques of Systematic Cause Analysis Technique (SCAT) and Root Cause Analysis (RCA), this study analyzed the root and direct causes of robot accidents that had occurred. Causes identified included physical hazards and complex combinations of hazards, such as psychological, organizational, and systematic errors. The requirements of risk assessments regarding robot operations were examined, and three case studies of robot-involved tasks were investigated. The three assessments presented were: camera module processing, electrical discharge machining, and a panel-flipping robot installation.ResultsAfter conducting RCA and comparing the three assessments, it was found that two-thirds of injury-occurring from robot accidents, causative factors included psychological and personal traits of robot operators. However, there were no evaluations of the identifications of personal aspects in the three assessment cases.ConclusionTherefore, it was concluded that personal factors of operators, which had been overlooked in risk assessments so far, need to be included in future risk assessments on robot operations.

Liability for Robots II: An Economic Analysis

This is the second of two companion papers that discuss accidents caused by robots. In the first paper (Guerra et al., 2021), we presented the novel problems posed by robot accidents, and assessed the related legal approaches and institutional opportunities. In this paper, we build on the previous analysis to consider a novel liability regime, which we refer to as “manufacturer residual liability” rule. This makes operators and victims liable for accidents due to their negligence—hence, incentivizing them to act diligently; and makes manufacturers residually liable for non-negligent accidents—hence, incentivizing them to make optimal investments in R&D for robots’ safety. In turn, this rule will bring down the price of safer robots, driving unsafe technology out of the market. Thanks to the percolation effect of residual liability, operators will also be incentivized to adopt optimal activity levels in robots’ usage.

Civil Liability for Robot Accident

Civil Liability for Robot Accident

When Robots Kill

Robots are increasingly interacting with people at the workplace as users or bystanders, hence, they ought to be reliable and safe. The rationale behind the study is to understand the causes of the rising workplace robot accidents by analysing a particular case for greater understanding. The article provides diverse perspectives on the probable causes and consequences of robot-related accidents and offers suggestions to mitigate these. It involves the application of the root cause analysis technique to identify the reasons behind the robot-related accident that resulted in the death of a worker and suggests remedies to do away with any such recurrence in the future. The study endeavours to bridge the research gap pertaining to robot-related accidents in the automotive industry.

Analysis of self‐reported accidents attributed to advanced manufacturing systems

AbstractReviewing past accidents is one way to identify hazards caused by advanced manufacturing systems and to manage accident prevention efforts. However, only a limited amount of data is currently available on industrial accidents due to advanced manufacturing environments, or these data cannot be easily distinguished from general industrial accident statistics. The main objective of this study was to examine the self‐reported accident data attributed to advanced manufacturing environments, based on the results of an anonymous questionnaire requesting information about one serious accident that occurred in the respondents' plant. The presented results are based on the analysis of 103 reported cases. A majority of the accidents occurred within the context of the stand‐alone automated equipment, followed by flexible manufacturing systems or cells. The injured personnel were operators of automated equipment (67%), followed by maintenance or repair personnel (20%). Typical activities performed at the time of the accident were related to production disturbances, such as clearing a blockage, fault finding or rectification, and adjustment of part or machine. In 55% of the analyzed accidents and 75% of the robot accidents, the manufacturing equipment was in the automatic operating mode. In 74% of the reported accidents, the safeguarding applied to the involved equipment was claimed to be inadequate. The above results suggest a need for the design of more effective safety systems that would not interfere with the human operator's work. The study results were also compared to results of previous studies of accidents in advanced manufacturing environments. @ 1995 John Wiley & Sons, Inc.

Worker selection of safe speed and idle condition in simulated monitoring of two industrial robots

Industrial robots often operate at high speed, with unpredictable motion patterns and erratic idle times. Serious injuries and deaths have occurred due to operator misperception of these robot design and performance characteristics. The main objective of the research project was to study human perceptual aspects of hazardous robotics workstations. Two laboratory experiments were designed to investigate workers' perceptions of two industrial robots with different physical configurations and performance capabilities. Twenty-four subjects participated in the study. All subjects were chosen from local industries, and had had considerable exposure to robots and other automated equipment in their working experience. Experiment 1 investigated the maximum speed of robot arm motions that workers, who were experienced with operation of industrial robots, judged to be 'safe' for monitoring tasks. It was found that the selection of safe speed depends on the size of the robot and the speed with which the robot begins its operation. Speeds of less than 51 cm/s and 63 cm/s for large and small robots, respectively, were perceived as safe, i.e., ones that did not result in workers feeling uneasy or endangered when working in close proximity to the robot and monitoring its actions. Experiment 2 investigated the minimum value of robot idle time (inactivity) perceived by industrial workers as system malfunction, and an indication of the 'safe-to-approach' condition. It was found that idle times of 41 s and 28 s or less for the small and large robots, respectively, were perceived by workers to be a result of system malfunction. About 20% of the workers waited only 10 s or less before deciding that the robot had stopped because of system malfunction. The idle times were affected by the subjects' prior exposure to a simulated robot accident. Further interpretations of the results and suggestions for operational limitations of robot systems are discussed.

A cause-and-effect analysis of robot accidents

Jiang, B.C. and Gainer, C.A., Jr., 1987. A cause-and-effect analysis of robot accidents. Journal of Occupational Accidents, 9: 27–45. Reported cases of robot accidents involving fatality, injury and non-injury were gathered from several sources (U.S., West Germany, Sweden and Japan). In cases where adequate information was available a cause-effect analysis of these accidents was performed. A total of 32 accidents were analyzed in the study. The accident effects were grouped according to who was injured (line worker, maintenance worker or programmer), the type of injury (pinch-point, impact or other), and the degree of injury (fatal, non-fatal-lost-work or non-fatal-no-lost-work). The accident causes were grouped into four categories (human error, workplace design, robot design and other) with the possibility that an accident could have more than one cause. Findings indicate that line workers are at greatest risk, followed by maintenance workers and programmers. Pinch-point accidents accounted for 56% of all accidents while impact accidents accounted for 44%. Most accidents were caused by poor workplace design (20 of 32 accidents) and human error (13 of 32 accidents). A comprehensive cause-effect analysis was performed on 25 of the accidents and includes: the accident source, the accident cause, the accident effect in terms of human injury, recommended guidelines to be implemented, and applicable safety standards in each case. Conclusions are drawn on the effectiveness of worker safety training and workplace design, both a result of suggested standards.

Systems safety for robots: An energy barrier analysis

Rahimi, M., 1986. Systems safety for robots: An energy barrier analysis. Journal of Occupational Accidents, 8: 127–138. The need for a comprehensive study of hazards caused by robot work environments is stressed. Based on previous data and robot accident reports, major factors contributing to robot accidents are classified and listed. System safety is introduced as an appropriate approach to analyze safety of semiautomated and automated robot systems. A general procedure for conducting system safety analysis is presented. Energy Barrier Analysis (EBA), a qualitative system safety technique, is applied to a general model of human—robot system. Major concepts of EBA are integrated in a stepwise approach for evaluating and designing robot safety systems. As the result of this application, specific solutions and recommendations are discussed.

Human factors in industrial robot safety

Parsons, H.M., 1986. Human factors in industrial robot safety. Journal of Occupational Accidents, 8: 25–47. Industrial robot safety could be advanced through participation of human factors scientists and practitioners who can join in investigating robot accidents and near accidents, propose additional robotic safety methods, conduct surveys and experiments, help develop standards and guidelines, and above all attempt to reduce “human error” that leads to accidents. Error types and sources are reviewed as well as techniques for reducing them. Reports are summarized that contained accident data, surveys, and experimentation. Japanese ergonomists have been in the forefront of robot safety research from a human factors perspective. A number of accident prevention methods are proposed that have received little or no attention.

A Safety and Collision Avoidance System for Industrial Robots

As more and more robots are installed in the industrial sector, the statistical likelihood for accidents involving robots increases unless careful design and implementation of safety features occurs. Some worker deaths related to robot accidents have been reported in Japan. Most workers and users of robots have embarked on a safety program depending on personnel training, preventative maintenance, and perimeter barriers and/or interlocks. Most of these necessary methods still do not address the issue of personnel required to be close to a robot during teaching, maintenance, and troubleshooting. The results of a research project underway at Rensselaer Polytechnic Institute to develop a computer controlled sensor system that will monitor the working envelope of a robot are discussed. If an dangerous situation occurs, this system will cause the robot to take corrective action to avoid personnel injury or damage to the robot or equipment.

Production Disturbances — A Safety Problem in Automatic Machines

This article is based on statistics of occured accidents at automatic machines, and on analyses of four different types of automatic equipment in the paper and engineering industry. The statistics showed that correction of disturbances was the most dangerous task at automatic machines. For example in 30 robot accidents two thirds occured, while the operator made a correction. In the cases studied the operators sometimes had to make advanced corrections, which often were dangerous. A summary of different kind of safety problems observed is given, and also some tentative suggestions how to prevent them. The list describes a number of factors to be taken into consideration in the design of automatic systems.

System Safety Approach to Robot Safety

The need and importance of considering robot safety issues are emphasized. Based on previous researches, major categories of robot accident causes are identified and listed. System safety is described as an appropriate approach to evaluating and designing robot safety systems. Then, qualitative and quantitative system safety techniques are introduced. Energy barrier analysis (a qualitative model) is selected and applied to a general human-robot system. Finally, as a result of this application, specific solutions and recommendations are discussed.