Sebastiano Chiodini

University of Padova | UNIPD · Department of Industrial Engineering

We present a collaborative visual localization method for rovers designed to hop and tumble across the surface of small Solar System bodies, such as comets and asteroids. In a two-phase approach, an orbiting primary spacecraft first maps the surface of a body by capturing images from various poses and illumination angles; these images are processed...

We present a flexible sensor fusion approach to retrieve scale information in monocular Visual Odometry (VO) through integrating range measurements from a wide variety of depth sensors spanning from small resolution Time-of-Flight cameras to 2D and potentially 3D LiDARs. While many algorithms exist in literature for range enhanced monocular VO, the...

In this paper, we present a user-friendly planetary rover's control system for low latency surface telerobotic. Thanks to the proposed system, an operator can comfortably give commands through the control base station to a rover using commercially available off-the-shelf (COTS) joysticks or by command sequencing with interactive monitoring on the s...

Pose estimation is critical for mobile robots to fulfill various tasks such as path following or mapping the environment. This is usually accomplished by Simultaneous Localization and Mapping (SLAM). However, computationally constrained systems, such as planetary rovers, rely on less intensive Guidance Navigation and Control (GNC) solutions general...

Obstacle mapping is a fundamental building block of the autonomous navigation pipeline of many robotic platforms such as planetary rovers. Nowadays, occupancy grid mapping is a widely used tool for obstacle perception. It foreseen the representation of the environment in evenly spaced cells, whose posterior probability of being occupied is updated...

In the current global context, where the issue of climate change has gained significant prominence, the ATEMO (Aerospace Technologies for Earth Monitoring and Observation) project introduces an innovative and scalable platform capable of measuring multiple environmental factors, including air pollution, light pollution, and vegetation analysis. Thi...

Point clouds are collected nowadays from a plethora of sensors, some having higher accuracies and higher costs, some having lower accuracies but also lower costs. Not only there is a large choice for different sensors, but also these can be transported by different platforms, which can provide different scan geometries. In this work we test the ext...

The multi-spectral data acquired with either satellite imagery, UAV or tethered and stratospheric balloons can be used to calculate vegetation indices directly related to the well-being of the crops providing a quantitative information about its health and growth. The vegetation indices are calculated combining measurements from different parts of...

This paper presents a machine learned feature detector targeted to event-camera based visual odometry methods for unmanned aerial vehicles trajectory reconstruction. The proposed method uses machine-learned features to enhance the accuracy of the trajectory reconstruction. Traditional visual odometry methods suffer from poor performance in low ligh...

Point clouds are collected nowadays from a plethora of sensors, some having higher accuracies and higher costs, some having lower accuracies but also lower costs. Not only there is a large choice for different sensors, but also these can be transported by different platforms, which can provide different scan geometries. In this work we test the ext...

This paper presents an experimental comparison of two types of LiDAR sensors for the navigation of rovers: a 360-deg FOV Scanning LiDAR, the Ouster OS1-32, and a non-repetitive scanning LiDAR, the Livox Horizon. The study aims to determine the performance differences between these two sensors in terms of accuracy, and reliability, which are crucial...

The ability to produce 3D maps with infrared radiometric information is of great interest for many applications, such as rover navigation, industrial plant monitoring, and rescue robotics. In this paper, we present a system for large-scale thermal mapping based on IR thermal images and 3D LiDAR point cloud data fusion. The alignment between the poi...

This paper presents the study of an optimized orbital configuration for a 3-axis stabilized 6U LEO nanosatellite that accommodates a polarized calibrator designed to transmit a calibrated signal to seven ground telescopes devoted to Cosmic Microwave Background (CMB) detection with an accepted maximum absolute pointing error of 4 arcmin; visibility...

In this work, we have analyzed the problem of relative pose initialization between two satellites: a chaser and a non-cooperating target. The analysis has been targeted to two close-range methods based on a monocular camera system: the Sharma-Ventura-D'Amico (SVD) method and the silhouette matching method. Both methods are based on a priori knowled...

The most effective expression of the 4.0 Era is represented by cyber-physical systems (CPSs). Historically, measurement and monitoring systems (MMSs) have been an essential part of CPSs; however, by introducing the 4.0 enabling technologies into MMSs, a MMS can evolve into a cyber-physical measurement system (CPMS). Starting from this consideration...

Terrain assessment is a key aspect for autonomous exploration rovers, surrounding environment recognition is required for multiple purposes, such as optimal trajectory planning and autonomous target identification. In this work we present a technique to generate accurate three-dimensional semantic maps for Martian environment. The algorithm uses as...

In this paper we present a simulation framework for the evaluation of the navigation and localization metrological performances of a robotic platform. The simulator, based on ROS (Robot Operating System) Gazebo, is targeted to a planetary-like research vehicle which allows to test various perception and navigation approaches for specific environmen...

Monocular vision systems allow compact and resource-constrained vehicles to perform online state estimation through Structure from Motion approaches. However, it is needed to integrate additional information to obtain a metric scale for the estimated trajectory. We propose a minimalistic approach based on the sensor fusion between a monocular camer...

Abstract: Monocular vision systems allow compact and resource-constrained vehicles to perform online state estimation through Structure from Motion approaches. However, it is needed to integrate additional information to obtain a metric scale for the estimated trajectory. We propose a minimalistic approach based on the sensor fusion between a mono...

In this work we describe a relative localization algorithm developed to estimate the position and the attitude (roll, pitch and heading angle) of a rover on the surface of Mars. The algorithm is designed to operate on a ground control center and to exploit all the computational power which is not available on the on-board computer and it serves to...

A deployed electrodynamic tether, provided with a tip-mass, can be used to deorbit a spacecraft at the end of its operative life. During the deployment of the tether from the spacecraft, the distance measurement between the spacecraft and the tip-mass may be useful to control the whole system. In the present work, three vision-based approaches to m...

Exploration vehicles need accurate localization for performing tasks such as autonomous navigation. Images captured from stereo cameras allow to estimate both the robot’s motion and the environment structure. This task is referred to as Visual Simultaneous Localization and Mapping (SLAM). With this work we evaluate some of the most famous solutions...

Nowadays, Motion Capture (MC) systems are used more and more to evaluate the accuracy of Visual Odometry and visual Simultaneous Localization and Mapping (SLAM) algorithms. However, the misalignment between the camera optical frame and the camera body frame, as tracked by a MC system, leads to a drift between the reconstructed trajectory and the re...

Ego-motion estimation and awareness of the surroundings are crucial tasks to perform for an exploration vehicle. Visual SLAM techniques allow to fulfill these needs by extracting meaningful information from images: changes in the appearance of the environments are used to simultaneously estimate both its structure and the relative motion of the cam...

An indirect measurement procedure is applied to the shutter mechanism mounted on the Wide Angle Camera and Narrow Angle Camera of the ESA Rosetta mission. The available direct measurements, such as the electrical current supplied to the actuation motors and the rotation of the motor shafts, are employed together with the kinematical and dynamical m...

During the development and testing phases of ego-motion estimation algorithms for robotics applications, such as Visual Odometry (VO) or visual SLAM, a ground truth trajectory is needed in order to evaluate their performances. Nowadays motion capture systems can reach millimetric accuracy thus they are a practical and accurate solution to give came...

The first of the two missions foreseen in the ExoMars program was successfully launched on 14th March 2016. It included the Trace Gas Orbiter and the Schiaparelli Entry descent and landing Demonstrator Module. Schiaparelli hosted the DREAMS instrument suite that was the only scientific payload designed to operate after the touchdown. DREAMS is a me...

An improved approach for the measurement of the relative pose between a target and a chaser spacecraft is presented. The selected method is based on a single camera, which can be mounted on the chaser, and a plurality of fiducial markers, which can be mounted on the external surface of the target. The measurement procedure comprises of a closed-for...

The inherent scale ambiguity in monocular vision is a well known issue that forces the integration of other sensory sources to obtain metric references. However, 2D or 3D LiDARs and RGB-D sensors, while guaranteeing metrological accuracy, impose a non negligible burden both in terms of computational load and power requirements limiting the feasibil...

In this work we have performed a sensitivity analysis of the Visual Position Estimator for Rover (VIPER) algorithm using data and images provided by NASA MER exploration rovers and NASA Mars Reconnaissance Orbiter. The algorithm retrieves the rover camera position and orientation relative to a Digital Elevation Model by comparing the skyline extrac...

A procedure to calibrate the relative position and orientation (extrinsic parameters) between a Time of Flight (ToF) camera and an RGB camera is presented. The proposed approach is particularly suited for ToF cameras characterized by very low resolution and a limited field of view. The presented experimental set-up is conceived to facilitate featur...

Stereo visual odometry is one of the most accurate dead-reckoning methods for estimating the motion of a moving vehicle but it strongly depends on a robust matching of the image features in the stereo frame. If a stereo camera is observing the environment from a critically small distance the two field of view can be subjected to poor or absent over...

In this paper we describe a Visual Odometry algorithm using a single RGB camera and a low resolution Time-of-Flight (ToF) camera for resolving the scale ambiguity in monocular vision. Two hybrid 3D-to-2D approaches for integrating direct depth measurements from the ToF with the RGB camera are compared. These two methods differ in the association of...

Abstract: In planetary exploration space missions, motion measurement of a vehicle on the surface of a planet is usually performed using a visual odometry method with two stereo global shutter cameras. In many technical applications, more favorable and cheaper rolling shutter cameras replace the global shutter ones. In this work, the visual odometr...

In this paper, we present an experimental analysis of how landmark distributions in a scene, as observed by a stereo-camera, affect Visual Odometry measurement performances. Translational and rotational tests have been performed in many different positions in an indoor environment. The Visual Odometry algorithm, which has been implemented firstly,...

An experimental comparison among visual odometry systems using lenses with three different focal lengths (an ultra wide angle, a medium wide angle and a telephoto lens) is presented. For each focal length, several translational and rotational tests are performed, taking into account and analyzing different positions of the system inside the laborat...

MISSUS experiment (Meteorological Integrated Sensor SUite for Stratospheric Analysis) is a multi-sensor scientific package dedicated to the characterization of thin atmosphere parameters, such as temperature and pressure, and to the attitude and trajectory reconstruction. In particular, MISSUS temperature sensor is the prototype of MarsTEM the inst...

MOPRHEUS (Mars Operative Rover of Padova Engineering University Students) is a planetary like rover under development at the University of Padova. It has been designed by a team of students as a testbed for planetary robotic exploration technologies, like soil and rocks extraction and sampling, and autonomous navigation in unstructured environment....

A vision based instrument able to measure the position and orientation of a spacecraft is described and calibrated from a metrological point of view. The instrument comprises a simple camera which observes the external surface of the satellite provided with fiducial markers and a software procedure which employs a closed-form and direct solution of...

The Temperature sensor of the DREAMS (Dust characterization, Risk assessment and Environment Analyzer on the Martian Surface) package, MarsTEM, on board the Exomars2016 Entry and Descent Module (EDM) was tested in the Moroccan desert during summer 2014. The sensor collected data for almost 3 days during which it measured stability of the atmospheri...

MarsTEM, the temperature sensor of the DREAMS (Dust characterization, Risk assessment and Environment Analyzer on the Martian Surface) package, which will fly on ExoMars 2016 EDM (Entry, Descent and landing demonstrator Module), will provide atmosphere temperature measurements near Mars' surface. As an effect of direct solar radiation, environment...

The Temperature sensor of the DREAMS (Dust characterization, Risk assessment and Environment Analyzer on the Martian Surface) package, MarsTEM, on board the Exomars2016 Entry and Descent Module (EDM) is designed to provide information on the variations of the Martian weather during the 2+2 days of mission during the dusty season on Mars. The presen...

In planetary exploration space missions, motion measurement of a vehicle on the surface of a planet is a very important task. The main contribution of this work is an experimental comparison among visual odometry systems using lenses with three different focal lengths (an ultra wide angle, a medium wide angle and a telephoto lens). The comparison i...

The DREAMS (Dust characterisation, Risk assessment and Environment Analyser on the Martian Surface) sensor suite is designed to investigate Martian meteorology and atmospheric electric properties at the ExoMars 2016 EDM (Entry, Descent and landing demonstrator Module) landing site. The DREAMS package will provides wind speed and direction measureme...

This paper describes the MISSUS experiment (Meteorological Integrated Sensor SUite for Stratospheric Analysis), developed at CISAS (Center for Studies and Activities for Space " G.Colombo ") with the aim to characterize the most significant environmental parameters of thin atmospheres and fully reconstruct attitude and trajectory. MISSUS flew onboa...