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The purpose of this paper is to describe a mechanical equilibrium model of a one‐end‐fixed type rubberless artificial muscle and the feasibility of this model for control of the rubberless artificial muscle. This mechanical equilibrium model expresses the relation between inner pressure, contraction force, and contraction displacement. The model validity and usability were confirmed experimentally.

Position control of a one‐end‐fixed type rubberless artificial muscle antagonistic drive system was conducted using this mechanical equilibrium model. This model contributes to adjustment of the antagonistic force.

The derived mechanical equilibrium model shows static characteristics of the rubberless artificial muscle well. Furthermore, it experimentally confirmed the possibility of realizing position control with force adjustment of the rubberless artificial muscle antagonistic derive system. The mechanical equilibrium model is useful to control the rubberless artificial muscle.

This paper reports the realization of advanced control of the rubberless artificial muscle using the derived mechanical equilibrium model.

This paper aims to present a new approach, called hybrid model reference adaptive controller or H-MRAC, for the hybrid controller (proportional-integral-derivative [PID + MRAC]) that will be used to control the position of a pneumatic manipulator.

It was developed a McKibben muscle using nautical mesh, latex and high-density polyethene connectors and it was constructed an elbow manipulator with two degrees of freedom, driven by these muscles. Then it was presented the H-MRAC control law based on the phenomenological characteristics of the plant, aiming at fast response and low damping. Lyapunov's theory was used as the project methodology, which ensures asymptotic stability for the control system.

It was developed a precise control system for a pneumatic manipulator and the results were compared to previous research.

In collaborative robotics, human and machine occupy the same workspace. This research promotes the development of safer and more complacent mechatronic systems in the event of collisions.

As a practical implication, the research allows the substitution of electric motors by McKibben muscles in industrial robots with high accuracy.

The pneumatic manipulator will make the human-robot physical interaction safer as it can prevent catastrophic collisions causing victims or equipment breakdown.

When compared to results in the literature, the present research showed a 37.51% and 36.74% lower global error in position tracking than MRAC and Adaptive proportional-integral-derivative (A-PID), respectively, validating its effectiveness.

This paper aims to discuss hybrid organizations whose business models blur the boundary between for-profit and nonprofit worlds. With the aim of understanding how hybrid organizations have developed commercially viable business models to create positive social and environmental change, the authors contend that hybrids are altering long-held business norms and conceptions of the role of the corporation in society. Building on an analysis of the most updated literature on hybrid organizations and with the use of case study approach, the purpose of this paper is to derive managerial lessons that traditional businesses may apply to innovate their business models.

This paper has a practical focus to help organizations to develop successful business strategies and design innovative business models. It applies emerging thinking on hybrid business models to provide new insights and ideas on the use of business models as tools for innovating and delivering value. To comply with this, first, the authors discuss the distinctive characteristics of hybrids and the hybrid business model through a concise but comprehensive review of all the literature on hybrid organization, which is still very recent. Second, we relied on a short case study that introduces information technology and digital innovation as the premises of the emergence of a new hybrid business model that adds additional elements to traditional business managers on how to learn from hybrid organizations’ avenues to innovate their business models.

In this paper, the authors aimed to shed light on the management of any organization or initiative that aims to embrace multiple and competing yet potentially synergistic goals, as is increasingly the case in modern corporations. Spotting hidden complementarities of antagonistic assets can be arduous, time-consuming, costly and risky, but businesses driven by innovation may want to keep a close eye on the expanding hybrid sector as a source of future entrepreneurial opportunities. To this regard, hybrid social ventures have the potential to shed light on ways to innovate traditional business models. The essence of studying hybrids is that firms may learn how to innovate their business models in ways that go beyond current conceptualizations, making their mission profitable, rather than making profit their only mission! The research design (literature analysis and case study) allowed the authors to disentangle different innovative business models that hybrids suggest highlight strengths and weaknesses of such business models, understand strategies and capabilities associated with hybrids and transpose all these lessons learned to traditional business managers who constantly struggle for innovation.

The main implication is that hybrid organizations may serve as incubators for new practices that can gain scale and impact by infusion into existing corporations. The authors can assist to a process of “hybridization” of incumbent firms, pushing the boundaries of corporate sustainability efforts toward strategies in which profit and social purpose share more equal footing.

Firms interested in benefiting from antagonistic assets that can have a dramatic impact on their business model innovation may want to consider some lessons: firms can attempt to build antagonistic assets into their mission, asking themselves what activities they can undertake with the potential to create (or erode) social, environmental and economic value and how these activities might be mediated by the context/environment in which they operate; they can partner with hybrids to benefit from them and absorb competencies from them, so to increase their likelihood to generate value-creating activities and to impact on wider range of stakeholders, including funders, partners, beneficiaries and communities; they can mimic hybrids on how to innovate their business model through the use of the “deliberate resource misfit” dynamic capability, mitigating negative impacts and trade-offs and maximizing positive value spillovers, both for the firms themselves and for the community.

Sharing know-how with hybrids opens up to ways to innovate business models, and hybrids are much more open to sharing lessons and encouraging others to copy their approaches in a genuine open innovation approach.

The main lesson businesses can take away from studying hybrids is that antagonistic assets – and not only profitable complementary ones, as the resource-based view would suggest – do not have to be a burden on profits. Hybrids ground their strategy first and foremost on their beneficiaries, thus dealing with a bundle of antagonistic assets. The primary objective of hybrids is thus to find imaginative ways of generating profits from their given resources rather than acquiring the resources that generate the highest profit. Profit is the ultimate goal of traditional businesses’ mission, but by making profit their only mission, firms risk missing out on the hidden opportunities latent in antagonistic assets. Learning from hybrids about how to align profits and societal impact may be a driver of long-term competitive advantage.

Manipulators in one form or another have been in existence for many hundreds of years with the design usually motivated by the task to be undertaken. Most often in robots this has led to a simple two fingered claw mechanism which has been adequate for many tasks but when the problem domain includes a varied range of delicate or easily damaged objects, one approach is to emulate those attributes of the human hand which make it such a versatile end‐effector. This paper will study two aspects of manipulator design: the construction of a dextrous hand with multi degree of control prehension, and the actuation systems to drive this hand that will make use of complaint drives to produce a “soft” but highly flexible mechanism to handle delicate products and materials.

The purpose of this paper is to focus on an engineering application of the vertebrate musculoskeletal system. The musculoskeletal system has unique mechanisms such as bi‐articular muscle, antagonistic muscle pairs and muscle‐tendon elasticity. The “artificial musculoskeletal system” is achieved through the use of the pneumatic artificial muscles. The study provides a novel method to describe the force property of the articulated mechanism driven by muscle actuator and a transmission.

A musculoskeletal system consists of multiple bodies connected together with rotational joints and driven by mono‐ and bi‐articular actuators. The paper analyzes properties of the musculoskeletal system with statically calculated omni‐directional output forces. A set of experiments has been performed to demonstrate the physical ability of the musculoskeletal robot.

A method to design a musculoskeletal system is proposed based on an analysis of the profile of convex polygon of maximum output forces. The result shows that the well‐designed musculoskeletal system enables the legged robot to jump 0.6 m high and land softly from 1.0 m drop off.

The paper provides a design principle for a musculoskeletal robot. The musculoskeletal system is the bio‐inspired mechanism for all multi‐degrees‐of‐freedom articulated devices, and has the advantages of optimized actuator configuration and force control.

This study aims to improve the muscle model control performance of a tendon-driven musculoskeletal system (TDMS) to overcome disadvantages such as multisegmentation and strong coupling. An adaptive network controller (ANC) with a disturbance observer is established to reduce the modeling error of the musculoskeletal model and improve its antidisturbance ability.

In contrast to other control technologies adopted for musculoskeletal humanoids, which use geometric relationships and antagonist inhibition control, this study develops a method comprising of three parts. (1) First, a simplified musculoskeletal model is constructed based on the Taylor expansion, mean value theorem and Lagrange–d’Alembert principle to complete the decoupling of the muscle model. (2) Next, for this simplified musculoskeletal model, an adaptive neuromuscular controller is designed to acquire the muscle-activation signal and realize stable tracking of the endpoint of the muscle-driven robot relative to the desired trajectory in the TDMS. For the ANC, an adaptive neural network controller with a disturbance observer is used to approximate dynamical uncertainties. (3) Using the Lyapunov method, uniform boundedness of the signals in the closed-loop system is proved. In addition, a tracking experiment is performed to validate the effectiveness of the adaptive neuromuscular controller.

The experimental results reveal that compared with other control technologies, the proposed design techniques can effectively improve control accuracy. Moreover, the proposed controller does not require extensive considerations of the geometric and antagonistic inhibition relationships, and it demonstrates anti-interference ability.

Musculoskeletal robots with humanoid structures have attracted considerable attention from numerous researchers owing to their potential to avoid danger for humans and the environment. The controller based on bio-muscle models has shown great performance in coordinating the redundant internal forces of TDMS. Therefore, adaptive controllers with disturbance observers are designed to improve the immunity of the system and thus directly regulate the internal forces between the bio-muscle models.

The application of the sliding mode control has two obstacle phenomena: chattering and high activity of control action. The purpose of this paper concerns a novel super-twisting adaptive sliding mode control law of a human-driven knee joint orthosis. The proposed control approach consists of using dynamically adapted control gains that ensure the establishment, in a finite time, of a real second-order sliding mode. The efficiency of the controller is evaluated using an experimental set-up.

This study presents the synthesis of a robust super-twisting adaptive controller for the control of a lower limb–orthosis system. The developed control strategy will take into consideration the nonlinearities as well as the uncertainties resulting from the dynamics of the lower limb–orthosis system. It must also guarantee a good follow-up of the reference trajectory.

The authors first evaluated on a valid subject, the performances of this controller which were studied and compared to several criteria. The obtained results show that the controller using the Adaptive Super-Twisting algorithm is the one that guarantees the best performance. Validation tests involved a subject and included robustness tests against external disturbances and co-contractions of antagonistic muscles.

The main contribution of this paper is in developing the adaptation super-twisting methodology for finding the control gain resulting in the minimization of the chattering effect.

The Equal Pay Act 1970 (which came into operation on 29 December 1975) provides for an “equality clause” to be written into all contracts of employment. S.1(2) (a) of the 1970 Act (which has been amended by the Sex Discrimination Act 1975) provides: