Nonholonomic Research Articles

LQR-based control strategy for improving human–robot companionship and natural obstacle avoidance

In the dynamic and unstructured environment of human–robot symbiosis, companion robots require natural human–robot interaction and autonomous intelligence through multimodal information fusion to achieve effective collaboration. Nevertheless, the control precision and coordination of the accompanying actions are not satisfactory in practical applications. This is primarily attributed to the difficulties in the motion coordination between the accompanying target and the mobile robot. This paper proposes a companion control strategy based on the Linear Quadratic Regulator (LQR) to enhance the coordination and precision of robot companion tasks. This method enables the robot to adapt to sudden changes in the companion target’s motion. Besides, the robot could smoothly avoid obstacles during the companion process. Firstly, a human–robot companion interaction model based on nonholonomic constraints is developed to determine the relative position and orientation between the robot and the companion target. Then, an LQR-based companion controller incorporating behavioral dynamics is introduced to simultaneously avoid obstacles and track the companion target’s direction and velocity. Finally, various simulations and real-world human–robot companion experiments are conducted to regulate the relative position, orientation, and velocity between the target object and the robot platform. Experimental results demonstrate the superiority of this approach over conventional control algorithms in terms of control distance and directional errors throughout system operation. The proposed LQR-based control strategy ensures coordinated and consistent motion with target persons in social companion scenarios.

A Path Planning and Tracking Control Algorithm for Multi-Autonomous Mobile Robot Systems Based on Spatiotemporal Conflicts and Nonholonomic Constraints

A Path Planning and Tracking Control Algorithm for Multi-Autonomous Mobile Robot Systems Based on Spatiotemporal Conflicts and Nonholonomic Constraints

How Much Better is Faster? Empirical Tests of QALY Assumptions in Health-Outcome Sequences.

This study was designed to test hypotheses regarding the path dependence of health-outcome values in the form of linear additivity of health-state utilities and diminishing marginal utility of health outcomes. We employed a discrete-choice experiment to quantify patient treatment preferences for major depressive disorder. In a series of choice questions, participants evaluated seven symptom-improvement sequences and out-of-pocket costs over 6-week durations. Money-equivalent values were derived from a deductive latent-class mixed-logit analysis. The discrete-choice experiment was completed by 751 respondents with self-reported major depressive disorder recruited from an online commercial panel. The class-membership probability was 0.83 for latent-class preferences consistent with supporting relative importance weights for all symptom-improvement sequences in the study design. First, we found strong support for diminishing marginal utility in symptom-improvement sequences. The money-equivalent value of an initial week of normal mood was $147 (95% confidence interval: $128, $166) and a second week of normal mood was $70 ($49, $91). Furthermore, for short treatment durations where conventional discounting was not a factor, equivalent changes in health status were valued more highly for an earlier onset of effect: holding subsequent symptom patterns constant, $338 (211, 454) versus $70 (49, 91) for improvements starting in week 2 versus week 3 and $147 ($128, $166) versus $29 (-$4, $64) for improvements starting in week 3 versus week 4. Our findings imply that conventional quality-adjusted life-year calculations in which health values are assumed to be path independent can understate the value of health improvements that appear earlier in a sequence.

Enhancing trajectory tracking accuracy in three-wheeled mobile robots using backstepping fuzzy sliding mode control

The rise in robotics technology has increased interest in ThreeWheeled Mobile Robots (TWMRs) due to their agility and adaptability across various applications. However, effectively controlling TWMRs presents a significant challenge owing to their inherent nonholonomic constraints, which restrict independent movement in all directions. Factors like sensor noise, nonlinear system dynamics, and uncertain system parameters also add to the complexity of controlling TWMRs. This research endeavors to enhance the precision of trajectory tracking in TWMRs. Specifically, it employs Backstepping Fuzzy Sliding Mode Control (BFSMC) with parameters optimized through Particle Swarm Optimization (PSO), coupled with the Extended Kalman Filter (EKF) for state estimation. The study conducts a comprehensive performance comparison between Backstepping Sliding Mode Control (BSMC) and Backstepping Fuzzy Sliding Mode Control(BFSMC) across various trajectory patterns, revealing substantial improvements in trajectory tracking accuracy with BFSMC. BFSMC demonstrates improvements in performance across various trajectory types when considering the integral time absolute error (IAE). Specifically, it achieves a 51.97% improvement for circular trajectories, an 82.09% improvement for infinity trajectories, and an 84.073% improvement for spiral trajectories. Moreover, BFSMC demonstrates superior robustness in the presence of disturbances, noise, parameter variations, and unmodeled dynamics compared to BSMC. Integrating the Extended Kalman Filter further improves accuracy, particularly in noisy conditions.

The influencing factors of willingness to participate in crop rotation and fallow: A behavioural economics perspective

AbstractCrop rotation and fallow practices are increasingly adopted to mitigate ecological resource pressures and accelerate the development of modern agriculture. These practices have significant implications for environmental protection, soil quality enhancement and the promotion of sustainable, high‐quality agricultural development. Despite their importance, empirical research on the factors influencing participation in crop rotation and fallow remains limited and comparative analyses of different compensation scenarios are scarce. This study, grounded in behavioural economics, utilizes data from the China Rural Revitalization Survey (CRRS) and employs propensity score matching (PSM) and binary logistic regression models to analyse farmers' behaviour regarding both induced and voluntary crop rotation and fallow. The research aims to identify the factors that influence farmers' decisions to engage in these practices. The findings indicate that, under a fixed subsidy standard, the participation rates for crop rotation and fallow were 14.5% and 5.4%, respectively. Among the farmers participating in crop rotation, 43.8% were induced, while 56.2% were voluntary. For fallow practices, 47.9% of the participants were induced and 52.1% were voluntary. In the context of induced crop rotation and fallow, ecological subsidies significantly increased farmers' willingness to participate (p‐value <.001). Conversely, in voluntary contexts, resource endowment had a significantly positive impact on crop rotation behaviour (p‐value <.1), whereas path dependence and policy awareness significantly constrained fallow behaviour (p‐value <.05). The impact of ecological subsidies on farmers' crop rotation and fallow behaviour varied significantly across different ecological regions, with other factors also exhibiting notable heterogeneity. The results of this research offer valuable guidance for the implementation of future crop rotation and fallow programmes. Additionally, they provide insights into the relationship between ecological subsidy systems and farmers' welfare in other underdeveloped areas, suggesting improvements and offering new perspectives for further research.

A Path Dependence Identification Method for Power MOSFETs Degradation Due to Bias Temperature Instability

A Path Dependence Identification Method for Power MOSFETs Degradation Due to Bias Temperature Instability

Almost-Poisson Brackets for Nonholonomic Systems with Gyroscopic Terms and Hamiltonisation

We extend known constructions of almost-Poisson brackets and their gauge transformations to nonholonomic systems whose Lagrangian is not mechanical but possesses a gyroscopic term linear in the velocities. The new feature introduced by such a term is that the Legendre transformation is an affine, instead of linear, bundle isomorphism between the tangent and cotangent bundles of the configuration space and some care is needed in the development of the geometric formalism. At the end of the day, the affine nature of the Legendre transform is reflected in the affine dependence of the brackets that we construct on the momentum variables. Our study is motivated by a wide class of nonholonomic systems involving rigid bodies with internal rotors which are of interest in control. Our construction provides a natural geometric framework for the (known) Hamiltonisations of the gyrostatic generalisations of the Suslov and Chaplygin sphere problems.

Towards holistic, participative and adaptable governance for offshore wind farm decommissioning

The earliest generation of offshore wind farms across Europe soon approach their end-of-life phase. Recent academic and societal attention has centred on the ‘artificial reef effects’ of offshore wind farms, triggering concerns regarding how to appropriately approach the decommissioning of the monopiles. Wind turbines and their foundations are jurisdictionally expected to be fully removed. Partial decommissioning, in which structures are left in place, is raised as a potential alternative that is anticipated to have ecological benefits over full decommissioning. Despite a strong growing scientific interest in OWF decommissioning, as well as an increasing public debate on the issue, a comprehensive approach to decommissioning decision-making has not yet landed in the actual regulatory processes. This gap is strikingly apparent in the Netherlands, where two OWFs will be decommissioned in the coming years. This paper explores where stakeholders believe the current bottlenecks exist, and how progress can be made towards decisive but inclusive decision-making. Based on individual co-creation sessions with concerned stakeholders, it offers multiple recommendations, including broadly supported criteria to be considered when comparing decommissioning alternatives, as well as underlying perceptions or patterns to be recognised, such as liability concerns, ecosystem valuation, lock-in and path dependency. The discussions and conclusions from this paper can be applied in all countries where decommissioning of OWFs is imminent, and thereby be used as a guide towards inclusive, adaptive and holistic governance within marine management.

초등학교 학생평가 정책에 대한 역사적 신제도주의 분석: 1999년 ~ 2024년을 중심으로

This study analyzed the evolution of elementary school student assessment policies from 1999, when performance assessment was introduced, through June 2024. It focused on structural, institutional, and actor contexts, dividing the analysis into three phases: the introduction of performance assessment, the abolition of summative assessment, and the development of assessment practices. Initially, both “path creation” and “path dependence” were observed, as performance assessments were introduced while traditional assessments persisted. In the abolition phase, process-oriented assessments marked a “fork in the path.” Finally, the development phase saw performance assessments becoming established, with new adaptive and customized assessments emerging, driven by edu tech companies. Although these changes haven’t led to institutional reforms yet, shifts in assessment paradigms were evident. The study recommends future policies consider the structural context and incorporate feedback from educators.

The effect of government investments on the environment: An empirical investigation of OECD countries

Sustainable development and climate change mitigation have become key priorities of economic policy. These priorities also remain relevant in the government investments. However, theoretical approaches indicate that government investments have both favourable and detrimental effects on environmental quality. Besides, the current literature has dealt with the impact of government expenditures in general. Based on this theoretical foundation and literature motivation this study addresses the impact of government investments on carbon emissions, in the case of 38 Organisation for Economic Co-operation and Development countries. For this purpose, in the models estimated for 2 different indicators of carbon emission, besides the lagged carbon emissions, income level, industrial production, energy intensity and renewable energy variables, government investments were also included into the analysis as additional explanatory variable. Considering the dynamic nature of our model, we implemented the system generalized method of moments on panel data and the findings of all different estimates demonstrate that government investments increase environmental pollution. Furthermore, our findings indicate that the path dependence of carbon emissions is strong and point to the carbon-mitigating effect of income level and renewables, and the carbon-increasing effect of industrial production and energy intensity. Our results support the pro-market view on the environmental impact of government investments and point to environmental efficiency problems arising from the decision-making processes of government investments. Furthermore, our results are not in favor of the opinion that government investments are decided based on social costs and social benefits, including externalities, and therefore have a long-term sustainability perspective.

Anti-corruption and firm innovation: political path dependence perspective

ABSTRACT Drawing on the concept of political path dependence, we hypothesise a positive impact of anti-corruption measures on firm innovation, illustrating how businesses can benefit from both eliminating illegal political ties (‘cleaning house’) and cultivating lawful relationships with the government (‘hosting new guests’). By analysing a sample of A-share listed companies from 2010 to 2015 using the PSM-DID model, we demonstrate that anti-corruption campaigns enhance innovation performance. Specifically, anti-corruption efforts sever the nexus of interests between government and businesses, curbing corporate expenditures on rent-seeking activities. Firms located in regions with stringent governmental oversight have experienced significant improvements in innovation outputs following the implementation of anti-corruption policies, particularly private-owned enterprises. This study provides empirical support for the benefits of anti-corruption from the perspective of political path dependence, offering valuable insights for governments aiming to bolster firm innovation through improved public governance and legal frameworks.

The constitutional codification of academic freedom over time and space

Abstract This article explores the global spread of domestic codifications of academic freedom norms by mapping constitutional provisions over time and space. Drawing on the new Academic Freedom in Constitutions dataset, the study evaluates several hypotheses that may explain the norm’s geographically diverse, yet comparatively limited, adoption in 52 per cent of constitutions today. The descriptive analysis of constitutional adoption patterns suggests that the as yet large pockets of absence are a result of the fact that academic freedom was not included as a fundamental right from the early days of constitution-making, combined with its close link to higher education development, thus locking many countries into a path dependency of early constitutions exclusive of academic freedom norms. The availability of relevant models in nearby countries, together with higher education expansion, are key facilitators of academic freedom adoption at the critical time of a constitutional reform process. Diverse countries in different regions acted as norm entrepreneurs, often motivated to domestically protect academic freedom, thus leading to the emergence of regional and other clusters of academic freedom reference types. A sizeable proportion of insincere adopters further suggests that, in some regions, academic freedom serves as a legitimizing international norm.

The social shaping of biotechnological innovation. The case of Covid-19 protein vaccine in Cuba and the US

AbstractLike other technologies, vaccines are socially shaped by socio-economic, political and organisational factors. Property rights, value capture strategies and public innovation policies guide research teams in the biochemical design of vaccines, with inevitable consequences for their price and accessibility. The Covid-19 pandemic provided an opportunity to analyse this institutional shaping process and its consequences for global public health from a political economy perspective. Indeed, the same type of invention, a recombinant protein vaccine, was simultaneously and originally developed in the US and Cuban biopharmaceutical industries and in the field of philanthropic Open Innovation. The article shows, through empirical research that collected direct testimony from scientists and privileged observers of the vaccine development fields, how certain norms and values characteristic of the US industry (financialization, assetization and de-risk) created a path dependency in the use of proprietary and experimental biotechnologies that made the US vaccine Nuvaxovid more expensive and complex to produce, but no more effective and safe than Abdala, Soberana 02 and Corbevax. In addition, the institutional constraints of the US biopharmaceutical industry on radical innovation, even within a mature biotechnology platform such as protein vaccines, would have resulted in a competitive disadvantage for Nuvaxovid, which was as expensive as an mRNA vaccine but less rapid to market and less reliable in delivery. The case of protein vaccines against Covid-19 thus shows how the institutional architectures of techno-scientific capitalism create not only inequalities but also inefficiencies, and that an innovation path with excellent results is possible even in competition where the market is not the dominant order of worth.

Path dependence in environment-related innovation: evidence from listed firms in China

ABSTRACT This paper studies the path dependence effect in corporate innovation based on the patent data of Chinese listed firms. The results provide robust evidence of the path dependence in technology innovation. The accumulated stock of brown patents reduces the ratio of green patents to total patents newly granted, thus inhibiting green structural changes in innovation. The accumulated stock of green patents increases the ratio of green patents in total patents granted, promoting structural change towards green innovation. The path dependence effect exists in both green inventions and green utility model patents. The heterogeneity analysis shows that both brown and green patent stocks of heavy polluting firms have a weaker effect on the ratio of green inventions than non-heavy polluting firms. The negative path dependence effect of brown patents on green innovation is stronger in firms with large scale, state ownership, and a high level of environmental regulation. However, the negative path dependence effects on green innovation can be alleviated for firms with superior environmental and financial performance. This suggests that the government has to create economic incentives to break the path dependence and encourage firms to engage in green innovation.

How enterprises in the digital age can “break through the cocoon and become new”: a study based on social media strategic capability

PurposeSocial media is booming in the digital age, and its rich availability provides many opportunities for companies to innovate across borders. In reality, how enterprises use social media to achieve cross-border innovation also faces important challenges such as breaking path dependency.Design/methodology/approachThis paper explores how social media can facilitate cross-border innovation from the perspective of strategic capability, combined with the path dependency theory and attention-based view. Hierarchical regression analysis and bootstrap method are adopted to test the hypotheses based on survey data provided by 173 firms in China.FindingsThe findings show a positive relationship between social media strategic capability and cross-border innovation, with path dependency playing a mediating role. In addition, two internal and external contextual factors, namely customer embeddedness and competitive pressure, play moderating roles, with customer embeddedness negatively moderating the negative relationship between social media strategic capability and path dependency and competitive pressure negatively moderating the negative relationship between path dependency and cross-border innovation.Originality/valueThese findings provide not only new insights into social media and cross-border innovation but also theoretical guidance on how companies can effectively use social media in practice.

Design and Implementation of a Discrete-PDC Controller for Stabilization of an Inverted Pendulum on a Self-Balancing Car Using a Convex Approach

This paper presents a trajectory-tracking controller of an inverted pendulum system on a self-balancing differential drive platform. First, the system modeling is described by considering approximations of the swing angles. Subsequently, a discrete convex representation of the system via the nonlinear sector technique is obtained, which considers the nonlinearities associated with the nonholonomic constraint. The design of a discrete parallel distributed compensation controller is achieved through an alternative method due to the presence of uncontrollable points that avoid finding a solution for the entire polytope. Finally, simulations and experimental results using a prototype illustrate the effectiveness of the proposal.

Mining industry development, enforcement intensity of security policy and intra-city development disparity

China, the world's largest developing country, is rich in mineral resources, albeit unevenly distributed geographically. Some cities with a surplus of mineral resources may form path dependence on these natural resource industries, leading to imbalanced urban development and widening development disparities within cities. However, in the event of safety incidents in the mining industry, local governments are compelled to regulate the excessive development of the mining sector and enhance the enforcement intensity of safety production policies. This study, based on the measurement of the Gini coefficient using nighttime light data for 281 prefecture-level cities in China, manually compiled the locations and death tolls of mining industry production safety incidents from 2001 to 2020, established an empirical analysis framework based on the instrumental variable two-stage least squares method. The research findings indicate: (1) Since the beginning of the 21st century, China's mining industry has experienced significant growth propelled by market-oriented reforms. However, it has also played a notable role in widening development disparities within cities. Robust results were obtained through instrumental variable estimation using the standard deviation of urban ground slope as a geographical indicator. (2) The occurrence of safety incidents in the mining industry will immediately escalate the enforcement intensity of regional safety policies, creating a significant inhibitory impact on alleviating the widening development disparities within cities caused by the expansion of the mining industry. In the case of larger safety incidents with a death toll of 3 or more, this impact will become even more pronounced. (3) Heterogeneity analysis reveals that the outlined mechanism is prominently present in the middle area, where the mining industry is relatively developed. In contrast, there is no significant correlation between the occurrence of safety accidents and the escalation of safety policy implementation intensity in the economically developed eastern region and the western region with lower levels of infrastructure development. However, in cities with a higher proportion of the mining industry, the aforementioned relationships remain stable. (4) Once a mining accident involving fatalities occurs in a prefecture-level city, local governments generally strengthen the enforcement of safety policies, comprehensively eliminate hidden dangers in production safety. This shift leads to a reversal in the impact of the mining industry on the development disparity within the city, changing from an expansion to a reduction effect. Moreover, this reduction effect persists for five years. In the case of a serious safety production incident resulting in 10 or more deaths, the impact of increased implementation of safety policies also extends for a prolonged period of five years. This article makes a clear marginal contribution to enrich the study on the effects of China's mining industry safety policies.

Metastable Liquid–Liquid Phase Separation and Aging Lead to Strong Processing Path Dependence in Mini‐Spidroin Solutions

AbstractRecombinant silk proteins provide a route toward sustainable and biocompatible materials. For making such materials, the assembly process from dilute protein into a functional material is central. The assembly mechanism in engineered materials is by necessity different from the natural ones—this poses challenges but also opens opportunities for scaling up and for developing novel properties. The phase behavior of a mini‐spidroin, NT‐2Rep‐CT is studied, which is a widely studied variant of recombinant silk. NT‐2Rep‐CT can be triggered to assemble by lowering the pH, but even at high pH—considered as storage conditions—it can be in various states, such as forming condensates, clusters, gels, and soluble protein. It is shown how its assembly phases evolve through both metastable and dynamically arrested states. The observed behavior of silk protein solutions is highly complex, and elements thereof from phase diagrams associated with polymers, colloidal systems, and globular proteins are found. Based on the characterization of cluster formation and structural intermediates, a minimalist phase diagram is proposed for NT‐2Rep‐CT and argues that the understanding and insight into silk assembly via its phase behavior, and especially the arrested states, is central for designing recombinant silk proteins and their processing for materials applications.

Transboundary Water Management in Central Asia and the Iberian Peninsula: Path Dependence Approach

This article examines the historical background and the state of the art of transboundary water management in the Central Asian region, which includes the republics of Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, and Uzbekistan, on one hand, and the Iberian Peninsula, which consists of the Kingdom of Spain and the Republic of Portugal, on the other hand. These distances from each other regions are studied for the reason that both of them are located in arid landscapes and further climate change is posing grave challenges to transboundary water security. By highlighting the differences and similarities in the water management practices of Central Asia and the Iberian Peninsula, this article employs a path-dependence approach to shed light on new perspectives on good water management. As a result of identified opportunities, the Central Asian states could enhance their policy in the water management system and adopt new measures based on positive foreign experience.

Urban environmental regulation, firms’ emission reduction strategies and labor demand: Evidence from China

Air pollution affects people's livelihoods, and China's environmental governance is a defensive battle that must be fought. Combining several comprehensive datasets, this study uncovers the underlying mechanisms of urban environmental regulation that affect labor demand from the perspective of firms’ choice of emission reduction strategies. Utilizing a difference-in-differences method, this study finds that on average, the Key City Demarcation Scheme for Air Pollution Prevention and Control (KCDS) has a drive-out effect on employment while improving urban environmental quality, making it difficult to achieve the double-dividend of de-pollution and employment promotion. These conclusions still hold after considering various specification checks, including the instrumental variable method. Underlying mechanisms indicate that manufacturing firms strengthen both front-end productive “changes-in-process” and non-productive “end-of-pipe” treatment to respond to stricter urban environmental enforcement, and ultimately, KCDS has triggered a drive-out effect on employment. Heterogeneous effects investigate that firms’ emission reduction strategies have path dependence and that the drive-out effect on employment is particularly pronounced for large-scale, technology- and capital-intensive domestic firms in large cities. This study provides policy insights for the smooth realization of the urban green transformation while safeguarding the livelihood of society.