Francesco Mondada

Design of Magnetic Switchable Device (MSD) and applications in climbing robot

A Magnetic Switchable Device (MSD) is a ferromagnetic circuit using permanent magnets where the flux can circulate between different paths when its configuration is changed. This routes or cancels the flux through specific surfaces, and thus turns on or off adhesion forces.We present classic and innovative magnetic configuration to realize powerful MSD. We designed and prototyped some miniature systems and give their characteristics. Finally various robotics applications for gripper, anchor and climbing robot are unveiled where the MSD solution has proved to be advantageous.

A review: Can robots reshape K-12 STEM education?

Can robots in classroom reshape K-12 STEM education, and foster new ways of learning? To sketch an answer, this article reviews, side-by-side, existing literature on robot-based learning activities featuring mathematics and physics (purposefully putting aside the well-studied field of “robots to teach robotics”) and existing robot platforms and toolkits suited for classroom environment (in terms of cost, ease of use, orchestration load for the teacher, etc.). Our survey suggests that the use of robots in classroom has indeed moved from purely technology to education, to encompass new didactic fields. We however identified several shortcomings, in terms of robotic platforms and teaching environments, that contribute to the limited presence of robotics in existing curricula; the lack of specific teacher training being likely pivotal. Finally, we propose an educational framework merging the tangibility of robots with the advanced visibility of augmented reality.

MagneBike: Compact magnetic wheeled robot for power plant inspection

The MagneBike robot is a magnetic wheeled robot designed for the inspection of ferromagnetic structures in power plants, especially steam chests. This video first presents the robots locomotion concept, i.e. two aligned magnetic wheels integrating lateral lever arms, that allow the robot to pass over complex combinations of obstacles. Laboratory and field experiments show the high mobility of the robot. This video also describes the localization and mapping strategy that consists in combining 3D odometry with 3D scanning and scan registration. An animation of the 3D reconstruction of the environment shows that the localization procedure allows to provide the necessary 3D visual feedback for the remote user or for inspection mission planning.

Tremo: an inspection climbing inchworm based on magnetic switchable device

TREMO is a compact magnetic climbing inchworm with the capability to move in complex ferromagnetic environments. The robot fits inside a cylinder of 500 mm in height and 120 mm in diameter for an approximate weight of 800 g. It has a modular configuration based on three energy autonomous sub-systems: an arm and two feet. The arm has five degrees of freedom. It has a central articulation with a stroke of 270°. Both ends of the arm have an innovative articulation based on a differential system. This allows unlimited rotation of 360° in the heading angles and 180° in the elevation angle. At both ends of the arm a camera is mounted. The feet are donut-shaped and are mounted around the camera. The climbing ability is based on the advantageous properties of Magnetic Switchable Devices (MSD) [1]. Each feet of the robot embeds three MSD for better compliance and stability of the adhesion to the surface. The three MSD of one feet together with their motors weight 32 g and can hold above 90 N.

Climbing robot with thermal glue

Climbing robots require an adhesion principle in order to overcome gravity. Many physical principles have been used. In this work, the use of thermal glue is proposed. The implementation of miniature thermal glue dispenser is presented with experimental results. The adhesion force depends on the surface, but 7 N/cm^2 is achieved on aluminium and synthetic surfaces. Several ideas were tested to save energy for detaching the glue foot. A climbing robot using this innovative adhesion principle was built. The strength and disadvantage of this technique are presented. The system offers an alternative solution to other commonly used method.

How mimetic should a robotic fish be to socially integrate into zebrafish groups

Biomimetic robots are promising tools in animal behavioural studies. If they are socially integrated in a group of animals, they can produce calibrated social stimuli to test the animal responses. However, the design of such social robots is challenging as it involves both a luring capability including appropriate robot behaviours, and the acceptation of the robots by the animals as social companions. Here, we investigate the integration of a biomimetic robot driven by biomimetic behavioural models into a group of zebrafish (Danio rerio). The robot behaviours are based on a stochastic model linking zebrafish visual perception to individual behaviour and calibrated experimentally to correspond to the behaviour of zebrafish. We show that our robot can be integrated into a group of zebrafish, mimic their behaviour and exhibit similar collective dynamics compared to fish-only groups. This study shows that an autonomous biomimetic robot was enhanced by a biomimetic behavioural model so that it can socially integrate into groups of fish.

Building a safe robot for behavioral biology experiments

A robot accepted by animals as conspecific is a very powerful tool in behavioral biology, particularly in studies of gregarious animals. However in experiments where animals and robots share the same physical environment, there is always a risk of a robot accident that can lead to animal injuries. Safety regulations have to be developed to guide the design of an intrinsically safe robotic hardware and software. Currently this question is not addressed in experimental biology. In this paper, we present our efforts to build a safe robot for experimentation with domestic chickens. The methodology we use is based on robot safety studies done in the field of physical humanrobot interaction. The safety elements were introduced in the mechanical design of the robot, its control system and into the experimental environment. We show how in particular cases, when local information available to the robot is insufficient to detect an abnormal situation, the global information provided by the external vision system can be used by a novelty detection system based on extreme value theory. We believe that this study can be useful for robotic researchers providing robots for biological studies, as the concepts presented are universal and can be applied to other types of animals.

Cy-mag3De: magnetic climbing inspection robot

Cy-Mag3De is a magnetic climbing inspection robot with advanced mobility. It is based on an innovative, award-winning and patented magnetic design. Its mobility is further enhanced thanks to a novel active tail. The robot has a cylindrical shape of 80 mm in diameter and 233 mm in length and a weight of 1.6 kg. It is energy autonomous with distributed batteries, has a camera and sends wireless video feed-back to the remote user interface. The robot is very integrated, robust and allows excellent mobility and visual inspection in complex ferromagnetic environment. It opens new avenue for climbing magnetic inspection robots.

Magnetic wheels optimization and application to the MagneBike climbing robot

Magnetic wheels are a powerful solution to design inspection climbing robots with excellent mobility. Magnetic wheels optimization based on simulations and the results that were obtained on prototypes are presented. The measured adhesion was doubled between the classic configuration and a novel multilayer one sharing exactly the same four magnets and the same total volume of iron. This know-how is then applied to optimize magnetic wheels for the existing robot called MagneBike. The adhesion force has been multiplied by 2 to 3 times depending on the conditions. Those amazing improvements open new possibilities for miniaturization of climbing robots or payloads increase.

Tubulo II: magnetic climbing inchworm for inspection of boiler tubes

TUBULO II is a climbing inspection robot with for inner inspection of boiler tubes. Its locomotion principle is the inchworm type. The adhesion is realized with Magnetic Switchable Device [1]. The inner is able to operate within a tube of inner bore diameter of 25 mm or 1 inch. The robot is modular. The robot and locomotion principle are robust and withstand the harsh environment of corroded boiler tubes. The construction is resistant to water and ferromagnetic particles that separate from the wall. The robot achieves a mean speed of 18 cm/min.