Ball-and-socket joint pose estimation using magnetic field

Roboy 3.0 is an open-source tendon-driven humanoid robot that mimics the musculoskeletal system of the human body. Roboy 3.0 is being developed as a remote robotic body - or a robotic avatar - for humans to achieve remote physical presence. Artificial muscles and tendons allow it to closely resemble human morphology with 3-DoF neck, shoulders and wrists. Roboy 3.0 3-DoF joints are implemented as ball-and-socket joints. While industry provides a clear solution for 1-DoF joint pose sensing, it is not the case for the ball-and-socket joint type. In this paper we present a custom solution to estimate the pose of a ball-and-socket joint. We embed an array of magnets into the ball and an array of 3D magnetic sensors into the socket. We then, based on the changes in the magnetic field as the joint rotates, are able to estimate the orientation of the joint. We evaluate the performance of two neural network approaches using the LSTM and Bayesian-filter like DVBF. Results show that in order to achieve the same mean square error (MSE) DVBFs require significantly more time training and hyperparameter tuning compared to LSTMs, while DVBF cope with sensor noise better. Both methods are capable of real-time joint pose estimation at 37 Hz with MSE of around 0.03 rad for all three degrees of freedom combined. The LSTM model is deployed and used for joint pose estimation of Roboy 3.0's shoulder and neck joints. The software implementation and PCB designs are open-sourced under https://github.com/Roboy/ball_and_socket_estimatorComment: Accepted at the International Symposium on Robotics Research (ISRR) 202

Self-organized control of an tendon driven arm by differential extrinsic plasticity

With the accelerated development of robot technologies, optimal control becomes one of the central themes of research. In traditional approaches, the controller, by its internal functionality, finds appropriate actions on the basis of the history of sensor values, guided by the goals, intentions, objectives, learning schemes, and so forth. The idea is that the controller controls the world---the body plus its environment---as reliably as possible. This paper focuses on new lines of self-organization for developmental robotics. We apply the recently developed differential extrinsic synaptic plasticity to a muscle-tendon driven arm-shoulder system from the Myorobotics toolkit. In the experiments, we observe a vast variety of self-organized behavior patterns: when left alone, the arm realizes pseudo-random sequences of different poses. By applying physical forces, the system can be entrained into definite motion patterns like wiping a table. Most interestingly, after attaching an object, the controller gets in a functional resonance with the object's internal dynamics, starting to shake spontaneously bottles half-filled with water or sensitively driving an attached pendulum into a circular mode. When attached to the crank of a wheel the neural system independently discovers how to rotate it. In this way, the robot discovers affordances of objects its body is interacting with

Association of common genetic variants with brain microbleeds

OBJECTIVE: To identify common genetic variants associated with the presence of brain microbleeds (BMBs). METHODS: We performed geno

TAF Agile Framework

TAF Agile Framework addresses the challenge of providing a methods framework for agile mechatronic product development. It aims to reduce uncertainty towards the product within minimum time and resources by taking a holistic, interdisciplinary perspective on the product and iteratively increases knowledge by applying the scientific method to the domains of desirability, feasibility and viability. It crystallizes this knowledge by building prototypes and artifacts to disseminate it quickly throughout large teams. It integrates best practices from traditional mechatronic development (e.g. Munich Procedural Model) with methods inspired by lean startup, scrum and design thinking. It coordinates cross-functional teams and helps to identify critical functions in order to build the right things before building them right. TAF is applied wherever companies need to adapt to a changing market, where the current business model or rather product lost its viability and where mechatronic products are developed de-novo. In this study, TAF Agile Framework is deduced from the combined experience of 37 agile mechatronic development projects and evaluated with the results of 13 further projects during a two weeks lab course at TU Munich

Evaluation of a novel, patient-mounted system for CT-guided needle navigation—an ex vivo study

Purpose: To describe the features of a novel patient-mounted system for CT-guided needle navigation, the Puncture Cube System (PCS), and to evaluate the accuracy and efficiency of the PCS by (a) applying numerical simulations and (b) by conducting punctures using the system in comparison to punctures using the free-hand method (FHM). Methods: The PCS consists of a self-adhesive cube that is attached to the patient, with multiple through-holes in the upper and lower template plate and dedicated software that, using a computer vision algorithm, recognizes the cube in a planning scan. The target in the image dataset is connected by a line, here “virtual needle,” which passes through the cube. For any chosen path of the virtual needle, the entry points for the needle into the cube are displayed by the software for the upper and lower template on-the-fly. The possible exactness of the system was investigated by using numerical simulations. Next, 72 punctures were performed by 6 interventionists using a phantom to compare for accuracy, time requirement, and number of CT scans for punctures with the system to the FHM ex vivo (phantom study). Results: The theoretical precision to arrive at targets increased with the distance of the target but remained low. The mean error for targets up to 20 cm below the lower plate was computed to be well below 0.5 mm, and the worst-case error stayed below 1.3 mm. Compared to a conventional free-hand procedure, the use of the navigation system resulted in a statistically significantly improved accuracy (3.4 mm ± 2.3 mm versus FHM 4.9 mm ± 3.2 mm) and overall lower intervention time (168 s ± 28.5 s versus FHM 200 s ± 44.8 s). Furthermore, the number of CT scans was reduced to 2.3 versus FHM 2.8). Conclusion: The PCS is a promising technique to improve accuracy and reduce intervention time in CT-guided needle navigations compared to the FHM

The challenges of impact evaluation: Attempting to measure the effectiveness of community-based disaster risk management

Although disaster risk management is becoming increasingly important in development cooperation, there is still a lack of robust evidence regarding its effectiveness. Few studies based on a counterfactual have been conducted in the fields of disaster management and disaster risk reduction. This article describes a methodological approach to enabling more rigorous evidence-based decision-making in community-based disaster risk mitigation, and notably for assessing the degree to which it increases preparedness for the adverse effects of hazards in vulnerable communities. The effects of actions designed to reduce disaster-induced loss, damage, injuries, fatalities and resource degradation were evaluated at a Swiss and Honduran Red Cross’ intervention area in Honduras. Our results show that the intervention has had a significant positive effect in three important areas of resilience: knowledge and preparedness (e.g., existence of an early warning system); social cohesion (e.g., community institutions); and management of natural assets (e.g., firewood consumption). Our findings indicate that the intervention program has enhanced the capacities of treated communities to prepare for future hazards and to respond in case of an emergency at both household and community levels

Humanoid robots to mechanically stress human cells grown in soft bioreactors

For more than 20 years, robotic bioreactor systems have facilitated the growth of tissue-engineered constructs using mechanical stimulation. However, we are still unable to produce functional grafts that can translate into clinical use. Humanoid robots offer the prospect of providing physiologically-relevant mechanical stimulation to grafts and implants which may expedite their clinical deployment. To investigate the feasibility of a humanoid bioreactor, we have designed a flexible bioreactor chamber that can be attached to a modified musculoskeletal (MSK) humanoid robot shoulder joint. We demonstrate that fibroblast cells can be grown in this chamber while undergoing physiological adduction-abduction on the robotic arm. A preliminary evaluation of the transcriptome of the cells after 14 days indicated a clear influence of the loading regime on the gene expression profile. These early results will facilitate the exploration of MSK humanoid robots as a biomechanically more realistic platform for tissue engineering and biomaterial testing applications

Forschungsprojekt 'ReduSys': Kontaktreduzierte Pflege im klinischen Umfeld durch multimodale Systeme und Robotik

'''Hintergrund/Fragestellung:''' Die pflegerische Versorgung bei stationären Krankenhausbehandlungen weist enorme Herausforderungen auf, die durch Ausnahmesituationen wie die COVID-19-Pandemie zusätzlich verstärkt werden. Digitale Technologien halten stetig Einzug in unser Gesundheitssystem und können den Alltag von Pflegefachpersonen unterstützen und entlasten. Neben der Weiterentwicklung technischer Komponenten sollten dabei auch immer die Bedürfnisse des Personals an einen technisierten Berufsalltag berücksichtigt werden [1]. Das Verbundprojekt ReduSys hat zum Ziel, die Entwicklung und Erprobung eines multimodalen Verbundsystems aus drei Teilsystemen: * Das Medical Smart Bed „Medtress“ ermöglicht eine kontaktlose-kontinuierliche Erfassung von Vitalparametern und die automatische Trinkmengenaufzeichnung „PROST“ unterstützt die Überwachung der Flüssigkeitszufuhr. * „FLOW“ dient zur digitalen Übertragung von Gesundheitsdaten über Smart Devices. * Der ferngesteuerte humanoide Roboter „Roboy“ kann basale pflegerische Tätigkeiten übernehmen, besonders in Ausnahmesituationen (z.B. COVID-19-Pandemie). Die Steuerung soll über Embodiment-Konzepte basierend auf Augmented und Virtual Reality realisiert werden. Neben der technischen Entwicklung sollen folgende Forschungsfragen beantwortet werden: Welche Anwendungsmöglichkeiten sind für potentielle NutzerInnen für das Verbundsystem vorstellbar? Welche hemmenden und fördernden Faktoren gibt es bei der Implementierung in ein klinisches Setting? '''Methoden:''' Als theoretische Grundlage wurde das Medical Research Council (MRC) framework for developing and evaluating complex interventions gewählt [[2]. Das gesamte Forschungsvorhaben verfolgt einen partizipativen Ansatz, der insbesondere durch einen qualitativen und praxisorientierten Forschungsansatz umgesetzt wird [3]. Dabei ist angedacht das Pflegepersonal durch Workshops oder Gruppendiskussionen sowie standardisierte Zielgruppenbefragungen von Beginn an zu involvieren. '''Vorläufige/erwartete Ergebnisse, Ausblick:''' Die Ergebnisse der ersten Projektphase dienen als Grundlage für die Simulationen. Diese erfolgen zunächst digital mit sogenannten „Digital Twins“. Im Anschluss finden die Tests mit gesunden ProbandInnen statt, bevor in der finalen Projektphase die Prototypen in der Klinik erprobt werden. Neben Fragestellungen zu Usability und Akzeptanz werden ethische, soziale und rechtliche Fragen fokussiert. ''Gefördert durch das Bundesministerium für Bildung und Forschung (BMBF) mit FKZ 16SV8829'' '''Interessenkonflikte:''' Es liegen keine Interessenkonflikte vor. '''Literatur''' 1. Radic M, Vosen A. Ethische, rechtliche und soziale Anforderungen an Assistenzroboter in der Pflege : Sicht des Führungspersonals in Kliniken und Pflegeeinrichtungen [Ethical, legal and social requirements for assistive robots in healthcare : Viewpoint of management personnel in hospitals and nursing homes]. Z Gerontol Geriatr. 2020 Nov;53(7):630-636. Epub 2020 Oct 7. DOI: 10.1007/s00391-020-01791-6 2. Skivington K, Matthews L, Simpson SA, Craig P, Baird J, Blazeby JM, Boyd KA, Craig N, French DP, McIntosh E, Petticrew M, Rycroft-Malone J, White M, Moore L. A new framework for developing and evaluating complex interventions: update of Medical Research Council guidance. BMJ. 2021 Sep 30;374:n2061. DOI: 10.1136/bmj.n2061 3. von Unger H. Partizipative Forschung – Einführung in die Forschungspraxis. Wiesbaden: Springer VS; 2014