New Trends in Medical and Service Robots

The paper presents the design of a needle insertion module for robotic assisted transperineal prostate biopsy, using a commercially available biopsy gun. The module is designed to be used as an end-effector for different robotic systems suitable for this medical task. The geometric and kinematic parameters of the insertion module are presented in correlation with a set of experimental data that supplied critical inputs for the solution development.

Within the further development of a special mechanical representation of the human circulatory system the CVELoop at the Department of Cardiovascular Engineering at RWTH Aachen University, a contractive MockHeart was developed. This MockHeart simulates a healthy heart in the CVELoop. In opposition to all previous cardiovascular system simulators, the left ventricle is externally driven by several cam mechanisms. These cam mechanisms provide the necessary power to create the pressure-volume-work for the fluid circulation but also the important time dependent radial contraction, which is the most influential degree of Freedom in the human heart. The aim is to produce a MockHeart providing valid boundary conditions for the connected VAD (Ventricular Assist Device). The systematic approach of the development of the mechanism is performed based on an accurate measurement of the kinematic properties of a healthy human heart at RWTH Aachen University with the speckle tracking echocardiography-procedure.

Gait therapy is important to a person’s recovery following spinal cord or brain injury, stroke, lower extremity surgery, as well as with many chronic conditions (e.g., Parkinson’s disease or multiple sclerosis). Although some affordable equipment for adult gait rehabilitation exists, such equipment for adaptive gait rehabilitation across the spectrum of pediatric sizes is not commercially available. This paper presents design improvements for a new pediatric gait rehabilitation machine intended to address this technology gap. The design is in the style of elliptical machines but is synthesized to emulate the normal kinematic demands of walking. It includes a 7-bar linkage for each foot, a chain/sprocket coupling for left/right synchronization, and motorized speed control.

The assimilation of the surgical techniques by the resident doctors should not affect patients’ safety. Practicing certain surgical gestures in a repetitive manner allows a better understanding of the technique and the correct acquisition of the manual skills. The use of simulators as a part of the training programs has considerably reduced the number of surgical errors and has improved the operative time and the quality of robotic and laparoscopic surgical procedures. The latest technologies, like 3D vision, next generation instruments, the use of intraoperative imaging have enabled the development of minimally-invasive surgery, so that a number of laparoscopic and robotic procedures have become the standard of care. Our objective was to evaluate the manner in which the latest technologies influence the development of minimally invasive surgery (laparoscopic and robotic). Also, we assessed the main parameters that influence the learning curve of these two types of minimally invasive approach. We observed that the use of the robotic platform during the learning curve allows the performance of laparoscopic procedures with the same accuracy, but with much lower costs.

Rising from a chair is a fundamental movement in daily life and a prerequisite for independent functional ability. Yet, it remains one of the most biomechanically demanding activities as it requires high levels of neuromuscular coordination, muscle strength and postural control (Ellis et al. J Biomed Eng 6:113–120 (1984), [3]). While standing up is considered a natural ubiquitous skill it becomes increasingly difficult with age. To prolong the independence of elderly we present a novel computational design procedure for lift-assist devices that are individualized to the user while complying with the limited space within the chair. Given marker-based sit-to-stand motion data task positions are defined to carry out a finite position synthesis of a four-bar linkage that provides user-specific guidance of a seat. The four-bar linkage combined with the lower limb of a user generates a biologically inspired six-bar linkage. Thus, accomplishing a bio-kinematic design of linkages where this contribution provides an exemplary design session.

In this paper the ability of Virtual Embryogenesis system (VE) to initiate and facilitate the build process of a multi-robot organism is presented. According to a single genome, which is spread in the whole organism, substances (morphogenes) are diffused to all neighbouring robots within the organism and new modules are recruited to advance the building process. Different shapes can be built by this system using different, pre-evolved genomes. This ability to build a robotic modular organism is very stable and is not influenced by the environment the controlling genome has evolved in. The presented method is suggested to control modular robots in future applications in dynamic environments, e.g., in interaction with humans.

Current wearable robots mostly focus on applications in military, rehabilitation and load lifting in the health sector, while they are hardly used in industry and manufacturing. In this paper, a sensor and control concept for a wearable robot for assistance in manual handling of loads in industry is presented. Special requirements such as low costs, direct contact between the human and the load and easy set-up are addressed. A wall-mounted test stand of an actuated elbow joint was built up to evaluate the proposed sensors and control algorithms. By using a torque sensor in the elbow joint as reference it is shown that low cost force sensors in the forearm can be used to measure the human-robot interaction. A torque-based and a velocity-based impedance control approach are compared which allow the user to move freely while not handling any loads and which also allow to incorporate a human command signal for regulation of force support. The former is shown to be superior to the position-based approach. Further, the influence of the human impedance characteristics onto stability of the controllers is discussed.

The aim of this study is to develop a teleoperation system which will be used to support the endoscopic pituitary surgery procedures. The proposed system aims to enable the surgeon to operate with three different operation tools (one of them is the endoscope) simultaneously. By this way, it is expected that the productivity of the surgical operation will be improved and the duration of the operation will be shortened. In the proposed system, a main control unit that can be attached to any of the surgical tools that are used in the operation (other than the endoscope) will be developed to capture the motion of the surgeon’s hand motion as demanded by the surgeon, to process the captured motion and to send it to the robot that handles the endoscope. In this way, the endoscope will be directed simultaneously by the surgeon throughout the operation while he/she is using the other surgical tools with his/her two hands. In this paper, the study to determine the type and processing of information that is sent from the surgeon’s side to the endoscope robot is presented.

The design of a suitable controller that handles robot-human interaction is one of the critical tasks in rehabilitation robotics. For this purpose, an accurate model of the robot is required. The Universal Haptic Pantograph (UHP) is a novel upper limb rehabilitation robot that can be configured to perform arm or wrist exercises. This work is focused on the latter, solving the kinematic model by the use of the closure loop equations, while Lagrangian formulation is used to estimate the interaction force. In order to prove the effectiveness of the model, several experimental tests are carried out. Results demonstrate that the mean motion error is less than 1 mm, and the estimated force error less than \(10\%\).

In the previous years the scientific community dealt extensively with designing, developing and testing robot-based rehabilitation systems. Besides the benefits that resulted for disabled people, this twenty-year endeavor has helped us improve our understanding of the neuroplasticity mechanisms in the Central Nervous System (CNS) and how these are triggered through the interaction with the physical world and especially through interaction with robots. In these systems, most of the state-of-the-art arrangements are based on multi-Degree of Freedom (DOF) open kinematic chains. They also employ sophisticated control hardware as well as high-profile actuators and sensors. The state-of-the-art technology that is integrated in these arrangements, increases the cost and at the same time requires the presence of trained employees that are able to maintain and operate such systems. Another option, are mechanisms that are based on four- and six-bar linkages. These are closed kinematic chain designs that can generate a variety of paths, yet they can do so with much less flexibility and adaptation possibilities. Despite the reduced flexibility over their robotic counterparts these mechanisms are attractive due to their reduced cost, simplicity and low external power requirement. This paper elaborates on the synthesis, analysis, simulation and passive control of four-bar linkages that can be used in upper limb rehabilitation and extends previous work by simulating the mechanism-impaired user interaction using a dynamic multibody system model. The emphasis in this work has been on straight-line trajectory generation, but this established methodology can be applied for developing mechanisms with higher complexity and more complex trajectories.

The aim of the present study is to analyse conscious and unconscious processes using the paradigm of listener-speaker in neurotypical children aged 6 and 9 years old. The speaker was always a child; the listener was a human or a robot, i.e., a small robot which reacts to speech expression by nodding only. Physiological data, i.e., heart rate, as well as behavioral data, i.e., number of words in addition with reported feelings, were considered. The results showed that (1) the heart rate was higher for children aged 6 years old than for children aged 9 years old when the listener was the robot; (2) the number of nouns and verbs expressed by both age groups was higher when the listener was the human. The results are consistent with the idea that conscious and unconscious development would not only depend on natural environments but also on artificial environments represented by robots.

Robotic surgery is in continuous development proving to be not only a better therapeutic option in certain procedures but also a pioneer field in which research occupies a very important role. The history of robotic begins with science-fiction literature, but it profiles the industrial and also health robots that are nowadays used. Robotic surgery begins later on with modified industrial robots, but from that point it has its own development. This article is a short history of surgical robotics, continued with the presentation of some surgical robots currently used. At the end, the characteristics of the future surgical robot are discussed, as well a proposal for a minimally invasive SILS robot.

HiBSO is an active orthosis designed to assist the hip flexion-extension of the elderly. A fully autonomous system with untethered power electronics and energy supply is now available. Going beyond the restricted walking conditions of a treadmill unveils many opportunities for the understanding of human-robot interaction. Previous works have presented the mechanical design optimized for high transparency and light weight, while dedicated kinematics allow high torque for sit-to-stand transition and high speed for level walking. The control strategies are currently in the evaluation process. In this document, the recent improvements to the device will be described, from the mechanical design to the control electronics. Some specific aspects such as the remote communication for the controller are emphasized. The assessment of the power autonomy is addressed with two sessions of walking in different conditions, and revealed a maximum operating time of more than 80 min. In this context, the controller is based on adaptive oscillators for the gait detection and is combined with a 40% torque assistance based on biomechanics from the literature.

This paper presents an open-loop balance control for an active leg exoskeleton based on human balance strategies, and how the machine can balance itself according to perturbations. The control is designed to balance the exoskeleton with a view to assist a well and able operator that leads the movements of the coupled system {operator+exoskeleton}. It is inspired by biomechanic works showing that human balance relies on three strategies: the displacement of the center of mass, the contribution of each leg to produce efforts and stepping. We assimilate the exoskeleton to a Linear Inversed Pendulum model to describe its global behavior, and we use its capture point to identify a loss of balance situation possibly caused by the operator and adapt the reaction of the machine. Thanks to capture point’s dynamics regarding to the center of mass and the center of pressure, we are able to control the machine and bring it back into a stable situation.

In nature, the combination of processes of emotion and cognition has a deep impact on type and quality of reaction to environmental stimuli. In this work, we want to test the feasibility of artificial hormones in artificial neural networks. We take a minimal evolving neural network and look into the implications and opportunities of extending this model of communicating nodes, with one virtual hormone gland. To explore the differences in behavior, that we expect to develop with this modification, we modify an already well established model, the Braitenberg Vehicle. These vehicles were faced with a simple energy gathering task. The behavior, efficiency and fitness of these vehicles in identical environment, with the artificial hormone active and inactive, is examined. It shows, that the implementation of artificial emotion leads to an increase in efficiency of the evolved solution.

This paper describes some relevant legal aspects concerning non-social robots. Special attention is drawn to Person Carrier Robots (PCaR) and Physical Assistant Robots (PAR). Although concrete legal binding regulations concerning these two sub-types of Personal Care Robots (PCR) are missing, the insertion of this assistive technology into the market arises some legal and ethical concerns. The main concerns include: cognitive aspects involved in the use of the technology; data protection matters: the way roboticists can make their technology comply with to the new European General Data Protection Regulation; liability contexts depending on their degree of autonomy; privacy and autonomy issued; as well as understanding how the decrease in the human-human interaction could undermine the dignity of the person.

The paper presents the main components of the preliminary research in developing an IOS (Instructor Operator Station) as a testing system for components, algorithms and human reactions in related space applications i.e. spacecraft docking. The mechanical, actuating and control solution for the IOS test bench is considered. The contributions are the result of a joint activity between teams from the DSSL (Dynamic Systems Simulation Laboratory) and CESTER.

Rob’Autism proposes an approach to improve social skills of people with autistic spectrum disorders. The program focuses on linking voice to gestures, and checks the emotional effects of this linkage. Rob’Autism is divided into 20 sessions of 1 h each, alternating preparatory sessions and robotics sessions. During the preparatory sessions, the subjects register their voices reading a story. During the robotics sessions, the subjects program the robot gestures according to the registered voices. In this program, the robots are used as an extension, and not as a companion as traditionally performed in other research programs. Consequently, the subjects immediately use it for their communication with others, showing consequent improvements of their communication skills, inside and outside the sessions, in a very short time. The program has also proven to length in time, as 6 months after its end, its effects on the subjects can still be observed. This article review the preliminary results of Rob’Autism, validated with 6 young test subjects with autism, aged 11–15.

A shaking force balanced mechanism is a mechanism that does not exert dynamic reaction forces to its base and to its surrounding for any motion. For mobile mechanisms such as exoskeletons, humanoid robots, drones, and anthropomorphic hands force balance is an important property for, among others, their dynamic behavior, stability, safety, control, and low energy consumption. For the design of force balanced mechanisms with multiple closed loops it can be a significant challenge to obtain the balance conditions, especially when the mechanism consists of closed loops that depend on other closed loops. In this paper it is shown how with mass equivalent modeling the force balance conditions can be derived of a complex multi-degree-of-freedom parallel mechanism with multiple closed loops of which one or more depend on other closed loops. It is shown how such a mechanism can be divided in mass equivalent linkages such as mass equivalent dyads and mass equivalent triads for which each can be analyzed individually with principal vectors and linear momentum equations.

The paper presents a comparison between an experimental study of flexion-extension movement in human legs joints and numerical simulations on a virtual mannequin computed in ADAMS virtual environment. Using Biometrics system which is a data acquisition system based on electrogoniometers, data were collected for the right and left ankle, knee and hip during experimental gait overground on force platforms. The mean flexion-extension cycles for legs joints were obtained. The obtained experimental data series were be introduced as input data in the joints of the virtual mannequin and a walking simulation was performed in ADAMS environment software. The variation of ground forces during walking are obtained by experimental data and by virtual simulation.

In this paper a problem of controlling a lower limb exoskeleton during sit-to-stand motion (verticalization) in sagittal plane is studied. It is assumed that left and right sides of the exoskeleton are moving symmetrically. The main challenge in performing this motion is to maintain balance of the system. In this paper we use the zero-moment point (ZMP) methodology to produce desired trajectories for the generalized coordinates that would allow the system to remain vertically balanced. The limitations of this approach is that, it requires relatively accurate work of the feedback controller that ensures that the exoskeleton follows generated trajectories. In this work we use Iterative Linear Quadratic Regulator (ILQR) as a feedback controller in order to obtained the required accuracy. In the paper a way of trajectory generation that uses ZMP methodology is discussed, the results of the numerical simulation of the exoskeleton motion are presented and analyzed. A comparison between a natural human motion (for a human not wearing an exoskeleton) and the simulated motion of an exoskeleton using the proposed algorithm is presented.

In this article we introduce a variation of the Firefly-Slime mold-Taxis (FSTaxis) algorithm, which is an emergent gradient ascent solution using external environmental influences such as tides, wind among others. Such external environmental influences are useful sources of energy for movement. If utilized, this results in substantial energy saving compared to robots relying solely on propulsion. Assistance using external factors can be adopted by various types of service robots depending on their environment of operation (for example, rescue robots, robotic underwater exploration). The variant of the FSTaxis algorithm we present in this paper combines bio-inspired communication strategies to achieve gradient taxis purely based on neighbor-to-neighbor interaction and tidal movements for mobility. In this article, we discuss the modified algorithm in detail and further introduce first simulation results obtained using a multiagent simulation environment.