Robot Prototype Research Articles

A Gecko-Inspired Robot with a Flexible Spine Driven by Shape Memory Alloy Springs.

The majority of sprawling-posture quadrupedal vertebrates, such as geckos and lizards, adopt a cyclical lateral swing pattern of their trunk that is coordinated with limb movements to provide extraordinary flexibility and mobility. Inspired by the gecko's locomotory gait and posture, a gecko-like robot with a flexible spine driven by shape memory alloy (SMA) springs was proposed in this work. The static parameters of the SMA spring were experimentally measured, and the flexible spine driven by SMA springs can be deflected bidirectionally. A kinematic model of the spine mechanism was established, and the mathematical relationship between the thermodynamic behavior of the SMA springs and spinal deflection was systematically analyzed. When a gecko trots with a lateral swing pattern of its trunk, the body and the spine show a standing wave shape and a single-peak C-type curve, respectively. The lateral spine deflection and trotting gait were combined in a collaborative model of a flexible spine and limbs to describe in detail the specific relationships between leg joint variables and spine deflection angle. Planar motion tests of a prototype robot were also conducted by using four high-speed cameras to record the trajectory of each point of the body, which verified the proposed model. From the acquired results, it was demonstrated that, compared with a rigid body, a robot with a flexible spine has a longer stride length, higher speed, and a greatly reduced turning radius.

A novel wave-like crawling robot has excellent swimming capabilities

Multiple animals ranging from micro-meter scale bacteria to meter scale vertebrates rely on undulatory motion to propel themselves on land and in the water. This type of locomotion also appears in amphibious animals such as sea snakes and salamanders. While undulatory motion can be used for both crawling and swimming, it requires the coordination of multiple joints so that only a few robots have the ability to mimic this motion. Here, we report a new minimalistic method for both crawling and swimming based on producing a wave motion in the sagittal (vertical) plane. A robotic prototype AmphiSAW was developed to demonstrate this methodology in a variety of scenarios. AmphiSAW (using its wave mechanism only) crawled at 1.5 B s−1 and swam at 0.74 B s−1. The robot can be fitted with legs or wheels at the front, which can further increase its performance especially when crawling on uneven terrains. In addition to its high speeds, the robot has the lowest cost of transport among all amphibious robots reported in literature.

Towards A Physics-based Model for Steerable Eversion Growing Robots.

Soft robots that grow through eversion/apical extension can effectively navigate fragile environments such as ducts and vessels inside the human body. This paper presents the physics-based model of a miniature steerable eversion growing robot. We demonstrate the robot's growing, steering, stiffening and interaction capabilities. The interaction between two robot-internal components is explored, i.e., a steerable catheter for robot tip orientation, and a growing sheath for robot elongation/retraction. The behavior of the growing robot under different inner pressures and external tip forces is investigated. Simulations are carried out within the SOFA framework. Extensive experimentation with a physical robot setup demonstrates agreement with the simulations. The comparison demonstrates a mean absolute error of 10 - 20% between simulation and experimental results for curvature values, including catheter-only experiments, sheath-only experiments and full system experiments. To our knowledge, this is the first work to explore physics-based modelling of a tendon-driven steerable eversion growing robot. While our work is motivated by early breast cancer detection through mammary duct inspection and uses our MAMMOBOT robot prototype, our approach is general and relevant to similar growing robots.

In robot we trust? The effect of emotional expressions and contextual cues on anthropomorphic trustworthiness

Following the evolution of technology and its application in various daily contexts, social robots work as an advanced artificial intelligence (AI) system to interact with humans. However, limited research has been done to discuss the role of emotional expressions and contextual cues in influencing anthropomorphic trustworthiness, especially from the design perspective. To address this research gap, the current study designed a specific robot prototype and conducted two lab experiments to explore the effect of emotional expressions and contextual cues on trustworthiness via a combination of subjective ratings and physiological measures. Results showed that: 1) positive (vs. negative) emotional expressions enjoyed a higher level of anthropomorphic trustworthiness and visual attention; 2) regulatory fit was expanded in parasocial interaction and worked as a prime to activate anthropomorphic trustworthiness for social robots. Theoretical contributions and design implications were also discussed in this study.

3D Printing of Small‐Scale Soft Robots with Programmable Magnetization

AbstractSoft magnetic structures having a non‐uniform magnetization profile can achieve multimodal locomotion that is helpful to operate in confined spaces. However, incorporating such magnetic anisotropy into their body is not straightforward. Existing methods are either limited in the anisotropic profiles they can achieve or too cumbersome and time‐consuming to produce. Herein, a 3D printing method allowing to incorporate magnetic anisotropy directly into the printed soft structure is demonstrated. This offers at the same time a simple and time‐efficient magnetic soft robot prototyping strategy. The proposed process involves orienting the magnetized particles in the magnetic ink used in the 3D printer by a custom electromagnetic coil system acting onto the particles while printing. The resulting structures are extensively characterized to confirm the validity of the process. The extent of orientation is determined to be between 92% and 99%. A few examples of remotely actuated small‐scale soft robots that are printed through this method are also demonstrated. Just like 3D printing gives the freedom to print a large number of variations in shapes, the proposed method also gives the freedom to incorporate an extensive range of magnetic anisotropies.

Design and Function Evaluation of Line Follower Plant Sprayer Robot

Agriculture tools necessary for increasing food security in Indonesia. An automatic spraying for plant became one of the tool that help in pot plant maintenance. This study was developing a prototype of automatic line follower robot for spraying plant. Designing a new construction and adding a line follower sensor, this robot could move between plant pots with guidance of black line. Main chassis of this robot made from 3 mm aluminum plate with 50 cm length and 20 cm width. Control of this robot using Arduino Uno as microcontroller that could control the movement of the robot and also could control movement of nozzle and flow rate. Performance testing of this robot held inside the room with concrete floor and placed on the white fabric with black line as a guidance and sign to stop and spray. As the result, average linier speed for this robot was 0,7 m/s and flow rate for spraying was 8,9 ml/s with 89,5% accuracy.

Vulcano: A new robotic challenge for legged robots.

The Vulcano challenge is a new and innovative robotic challenge for legged robots in a physical and simulated scenario of a volcanic eruption. In this scenario, robots must climb a volcano's escarpment and collect data from areas with high temperatures and toxic gases. This paper presents the main idea behind this challenge, with a detailed description of the simulated and physical scenario of the volcano ramp, the rules proposed for the competition, and the conception of a robot prototype, Vulcano, used in the competition. Finally, it discusses the performance of teams invited to participate in the challenge in the context of Azorean Robotics Open, the Azoresbot 2022. This first test for this challenge provided insights into what the participants found exciting and positive and what they found less positive.

A Wind-Turbine-Tower-Climbing Robot Prototype Operating at Various Speeds and Payload Capacity: Development and Validation

The development of control technology on wind turbine application robots has played an integral role in facilitating the digitization of inspection and maintenance in the wind energy industry. This paper presents a wind-turbine-climbing robot that determines the service lifespan of the wind turbine components subject to its payload capacity. The model has four rubber wheels, as the driving mechanism for its locomotion is being supported by a Bowden cable as a winding mechanism for its adhesion. The design further incorporates an Arduino microcontroller, distance sensors, motors, and a step motor to form its electromechanical structure. The overall capability of the robot has been analyzed through its kinematics and dynamics. Practical indoor experiments using a wind turbine tower mockup have been conducted for the validation of the various speeds and payload capacity of the prototype. The results indicate the effectiveness of its driving and winding mechanism to climb at the various speeds and with or without a payload. The advantage of the operations of its mechanism conformed with the wind turbine application robots.

A Prototype of Garbage Picker Ship Robot Using Arduino Nano Microcontroller

This study aims to create a robot prototype for a garbage collection ship made using an Arduino nano microcontroller. The prototype of this garbage collection robot vessel is controlled by an Android smartphone application that is connected via Bluetooth. The prototype of the robot of the boat was made to deal with piles of garbage that can cause flooding. The method used in making the prototype ship robot along with the controller application begins with identifying the problem, namely the problem of piles of garbage, then needs analysis. Moreover, in this research, what will be developed is in terms of design, ship robot prototype, and ship robot controller design. Next is implementation and testing. The prototype of the garbage collection ship robot uses an Arduino nano microcontroller and in making a controller application using Android Basic 4. Then the trial stage was carried out on an Android smartphone. The results of this study are a prototype ship robot that can move according to commands through a controller application.

Precision-Driven Multi-Target Path Planning and Fine Position Error Estimation on a Dual-Movement-Mode Mobile Robot Using a Three-Parameter Error Model

The multi-target path planning problem is a universal problem to mobile robots and mobile manipulators. The two movement modes of forward movement and rotation are universally implemented in integrated, commercially accessible mobile platforms used in logistics robots, construction robots, etc. Localization error in multi-target path tracking is one of the crucial measures in mobile robot applications. In this article, a precision-driven multi-target path planning is first proposed. According to the path's odometry error evaluation function, the precision-optimized path can be discovered. Then, a three-parameter odometry error model is proposed based on the dual movement mode. The error model describes localization errors in terms of the theoretical motion command values issued to the mobile robot, the forward moving distances, and the rotation angles. It appears that the three error parameters follow the normal distribution. The error model is finally validated using a mobile robot prototype. The error parameters can be identified by analyzing the actual moving trajectory of arbitrary movements. The experimental localization error is compared to the simulated localization error in order to validate the proposed error model and the precision-driven path planning method. The OptiTrack motion capture device was used to capture the prototype mobile robot's pose and position data.

A Spiny Climbing Robot with Dual-Rail Mechanism.

Easy detachment is as important as reliable an attachment to climbing robots in achieving stable climbing on vertical surfaces. To deal with the difficulty of detachment occurring in wheeled and track-type climbing robots using bio-inspired spines, a novel climbing robot utilizing spiny track and dual-rail mechanism is proposed in this paper. The spiny track consists of dozens of spiny feet, and the movement of each spiny foot is guided by the specially designed dual-rail mechanism to achieve reliable attachment and easy detachment. First, the design of the climbing robot and the dual-rail mechanism are presented. Then, the dual-rail model is constructed to analyze the attaching and detaching movements of the spiny feet, and a mechanical model is established to analyze the force distribution on the spiny track. Finally, a robot prototype is developed, and the analysis results are verified by the experiment results. Experiments on the prototype demonstrated that it could climb on various rough vertical surfaces at a speed of 36 mm/s, including sandpaper, brick surfaces, concrete walls with pebbles, and coarse stucco walls.

An Electrostatic Locking Mechanism For Tendon-driven Surgical Robot

Variable stiffness surgical robots are capable of adapting to different surgical scenarios, providing enhanced stability during minimally-invasive surgeries. Prevalent methods for achieving variable stiffness, such as lockable mechanisms, granular jamming, and phase transition materials, have inherent weaknesses including difficulties in downsizing and issues related to excessive temperatures. In this paper, a novel lockable mechanism based on electrostatics is proposed, along with a tendon-driven surgical robot prototype that utilizes this locking mechanism to achieve variable stiffness. The proposed mechanism involves the installation of graphite electrode sheets at each joint, with silica gel being used as the dielectric material. By applying a high voltage to the electrode sheets, adjacent joints automatically absorb and restrict relative sliding, effectively preventing joint rotation and ensuring complete joint locking. An electrostatic adhesive braking force model for the robot is presented. Simulations and experiments conducted based on the robot prototype have been carried out to validate the locking capability of the proposed mechanism and the accuracy of the electrostatic adhesive braking force model.

Design and Autonomous Navigation of a New Indoor Disinfection Robot Based on Disinfection Modeling

The COVID-19 pandemic shows growing demand of robots to replace humans for conducting multiple tasks including logistics, patient care, and disinfection in contaminated areas. In this paper, a new autonomous disinfection robot is proposed based on aerosolized hydrogen peroxide disinfection method. Its unique feature lies in that the autonomous navigation is planned by developing an atomization disinfection model and a target detection algorithm, which enables cost-effective, point-of-care, and full-coverage disinfection of the air and surface in indoor environment. A prototype robot has been fabricated for experimental study. The effectiveness of the proposed concept design for automated indoor environmental disinfection has been verified with air and surface quality monitoring provided by a qualified third-party testing agency. Note to Practitioners—Robots are desirable to reduce the risk of human infection of highly contagious virus. For such purpose, a novel autonomous disinfection robot is designed herein for automated disinfection of air and surface in indoor environment. The robot structure consists of a mobile carrier platform and an atomizer disinfection module. The disinfection modeling is conducted by using the measurement data provided by a custom-built PM sensor array. To achieve cost-effective and qualified disinfection, a full-coverage path planning scheme is proposed based on the established disinfection model. Moreover, for specifically disinfecting the frequently contacted objects (e.g., tables and chairs in offices and hospitals), a target perception algorithm is proposed to mark the localization of these objects in the map, which are disinfected by the robot more carefully in these marked areas. Experimental results indicate that the developed disinfection robot offers great effectiveness to fight against the COVID-19 pandemic.

Digital Interactive Design and Robot-Assisted Preparation Experiment of Tooth Veneer Preparation: An in Vitro Proof-of-Concept

In the fixed prosthesis process dental prosthesis treatment, the dentist needs to conceive the morphology of the tooth preparation and make numerous micro-adjustments by manual operation. This study aims to establish a digital design system for accurate designing of veneer preparation and study the trajectory planning of the robot-assisted preparation. According to the standard operation requirements, the projection line segmentation method based on point drawing is proposed for interactive selection to ensure the margin smoothness of the preparation area. The preparation depth is parameterized, and the foldback point correction method based on secondary segmentation is used for repairing the offset preparation area to ensure surface smoothness. The fenestration preparation model was obtained in the digital interactive design software. The model is divided into two feature areas which are interpolated by the B-spline curve and NURBS surface, respectively. The isoparametric curve method is used to plan the preparation trajectory. The experimental and theoretical values of the target feature points from the X, Y and Z coordinate directions were also calculated and analyzed. The experiment is carried out by the physical prototype of the tooth preparation robot. The maximum error of the feature points on the preparation are 0.180 mm, 0.104 mm and 0.142 mm in X, Y and Z directions, respectively. The confidence interval of the system error is stable within 0.30 mm. The error of the feature points verifies the feasibility of the digital interactive design system and the correctness of the trajectory planning of tooth veneer preparation. The system could have the potential to assist dentists in the precise design of the veneer preparation, improve the processing efficiency and ensure the effect of tooth veneer prosthesis.

Intelligence and Motion Models of Continuum Robots: An Overview

Many technical solutions are bio-inspired. Octopus-inspired robotic arms belong to continuum robots which are used in minimally invasive surgery or for technical system restoration in areas difficult-to-access. Continuum robot missions are bounded with their motions, whereby the motion of the robots is controlled by humans via wireless communication. In case of a lost connection, robot autonomy is required. Distributed control and distributed decision-making mechanisms based on artificial intelligence approaches can be a promising solution to achieve autonomy of technical systems and to increase their resilience. However these methods are not well investigated yet. Octopuses are the living example of natural distributed intelligence but their learning and decision-making mechanisms are also not fully investigated and understood yet. Our major interest is investigating mechanisms of Distributed Artificial Intelligence as a basis for improving resilience of complex systems. We decided to use a physical continuum robot prototype that is able to perform some basic movements for our research. The idea is to research how a technical system can be empowered to combine movements into sequences of motions by itself. For the experimental investigations a suitable physical prototype has to be selected, its motion control has to be implemented and automated. In this paper, we give an overview combining different fields of research, such as Distributed Artificial Intelligence and continuum robots based on 98 publications. We provide a detailed description of the basic motion control models of continuum robots based on the literature reviewed, discuss different aspects of autonomy and give an overview of physical prototypes of continuum robots.

Prototype of 3-DOF Pick and Place Arm Robot

What we are witnessing today in terms of acceleration in manufacturing and production processes in factories would not have taken place without relying on robotic arms to accomplish routine work with better accuracy, fewer errors and a higher speed compared to the human element and because conducting experiments and modifying ready-made robots that operate on production lines and testing new software on them is expensive and not available in many cases, the idea stemmed from here in creating a prototype for a robotic arm that enables developers and researchers to test and develop their own software before adopting it, and this robot was characterized by ease of use and low cost compared to what is in the market with the possibility of controlling it in more than one way, as this research shows the method of designing and manufacturing a robotic arm of the type 3- DOF (3-Revolute joints) used to capture Various parts. Electromagnets of end effect or were used to pick up the pieces. This robotic arm was tested in an integrated environment using the MATLAB - Simulink program under different conditions, the first of which depends on the forward kinematics and the second mode of operation depends on the inverse kinematics, while the third mode was using the two types of Trajectory Planning (LSPB –Conic), Practical experiments of this robotic arm have shown high accuracy in performance, quick response in executing orders, and avoiding falling into Singularities due to setting mechanical and software restrictions for the robot.

The Control of an Aquatic Robot by a Periodic Rotation of the Internal Flywheel

This paper presents the design of an aquatic robot actuated by one internal rotor. The robot body has a cylindrical form with a base in the form of a symmetric airfoil with a sharp edge. For this object, equations of motion are presented in the form of Kirchhoff equations for rigid body motion in an ideal fluid, which are supplemented with viscous resistance terms. A prototype of the aquatic robot with an internal rotor is developed. Using this prototype, experimental investigations of motion in a fluid are carried out.

Towards a Discrete Snake-Like Robot Based on SMA-Actuated Tristable Modules for Follow the Leader Control Strategy

Snake-like robots applications include surveillance and exploration of confined environments where human presence is incompatible. The attractiveness of this type of mechatronic structure is notably linked to the modular character and the hyper-redundancy of their architecture, which gives it both mechanical robustness and great manoeuvrability. However, due to the large number of degrees-of-freedom, the use of advanced mathematical models are needed to asses the motion patterns and to simulate it. A new snake-like robot architecture is introduced in this paper together with the development methodology of a replicable multistable module. The interest of this contribution lies in the combination of the mechanical stability of the modules with an easy-to-use direct kinematic model, thus avoiding the need of complex control strategies. The design of one module exploiting the three stable states of a tristable flexible mechanism so as to orient the articulation of the module at three distinct stable angles is first presented. Then a prototype of a modular snake-like robot is built and experimentally evaluated. The prototype consists of 4 modules that can be individually oriented by <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\pm$</tex-math></inline-formula> 7.1 degrees. Each module measures 51.5 × 32 mm and weighs 2.5g. Thereby, this work provides the first results on the feasibility of this robotic architecture which consists of several multistable modules. A good agreement between the working space estimated with the direct kinematic model and experimental measurements is obtained. According to the fact that these are preliminary results, there is a 1.5% error between the experimental results and the models.

Design and Control for WLR-3P: A Hydraulic Wheel-Legged Robot.

The robot used for disaster rescue or field exploration requires the ability of fast moving on flat road and adaptability on complex terrain. The hybrid wheel-legged robot (WLR-3P, prototype of the third-generation hydraulic wheel-legged robot) has the characteristics of fast and efficient mobility on flat surfaces and high environmental adaptability on rough terrains. In this paper, 3 design requirements are proposed to improve the mobility and environmental adaptability of the robot. To meet these 3 requirements, 2 design principles for each requirement are put forward. First, for light weight and low inertia with high stiffness, 3-dimensional printing technology and lightweight material are adopted. Second, the integrated hydraulically driven unit is used for high power density and fast response actuation. Third, the micro-hydraulic power unit achieves power autonomy, adopting the hoseless design to strengthen the reliability of the hydraulic system. What is more, the control system including hierarchical distributed electrical system and control strategy is presented. The mobility and adaptability of WLR-3P are demonstrated with a series of experiments. Finally, the robot can achieve a speed of 13.6 km/h and a jumping height of 0.2 m.

Design and Motion Control of Spherical Robot With Built-In Four-Wheel Omnidirectional Mobile Platform

The objective of this paper is to propose a novel spherical robot with built-in four-wheel omnidirectional mobile platform. The employment of four-wheel structure helps to improve the friction coefficient and thus reduce the slipping motion. In addition, it increases the velocity augmentation factor, and thus compensation methods can be effectively implemented into the system to decrease the slipping motion further. Moreover, the traction force is increased and thus the loading capacity can be improved correspondingly. First, the schematic structure along with the operating principle of the proposed spherical robot is introduced. Then, the kinematic and dynamic models are formulated analytically. The slipping error between the omnidirectional wheels and the inner wall of the sphere is analyzed. The slip observer and the motion controller are designed, and their convergence is proved theoretically. Subsequently, simulation is conducted to validate the proposed slip observer that is in turn implemented into the motion controller. The trajectory tracking of the spherical robot on straight line and circle is verified. Following that, one research prototype of the spherical robot with built-in four-wheel omnidirectional mobile platform is developed. Experimental investigation shows that the research prototype embedded with the slip observer can achieve the trajectory tracking performance very well.