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Found 39 papers, 12 papers with code
Shonan Rotation Averaging: Global Optimality by Surfing SO(p)(n)
Shonan Rotation Averaging is a fast, simple, and elegant rotation averaging algorithm that is guaranteed to recover globally optimal solutions under mild assumptions on the measurement noise.
A Geometric Perspective on Fusing Gaussian Distributions on Lie Groups
Stochastic inference on Lie groups plays a key role in state estimation problems, such as inertial navigation, visual inertial odometry, pose estimation in virtual reality, etc.
Exploiting polar symmetry in designing equivariant observers for vision-based motion estimation
Accurately estimating camera motion from image sequences poses a significant challenge in computer vision and robotics.
Exploiting Equivariance in the Design of Tracking Controllers for Euler-Poincare Systems on Matrix Lie Groups
In this paper, we propose a group structure on the cotangent bundle of a Lie group and leverage this to define momentum and configuration errors for trajectory tracking drawing on recent work on equivariant observer design.
Exploiting spatial group error and synchrony for a unicycle tracking controller
Trajectory tracking for the kinematic unicycle has been heavily studied for several decades.
Synchronous Observer Design for Inertial Navigation Systems with Almost-Global Convergence
An Inertial Navigation System (INS) is a system that integrates acceleration and angular velocity readings from an Inertial Measurement Unit (IMU), along with other sensors such as GNSS position, GNSS velocity, and magnetometer, to estimate the attitude, velocity, and position of a vehicle.
A Note on the Extended Kalman Filter on a Manifold
With this structure, we show that a naive coordinate implementation of the EKF fails to account for geometry of the manifold in the update step and in the reset step.
High Frequency, High Accuracy Pointing onboard Nanosats using Neuromorphic Event Sensing and Piezoelectric Actuation
In this work, we develop a novel payload that utilises a neuromorphic event sensor (for high frequency and highly accurate relative attitude estimation) paired in a closed loop with a piezoelectric stage (for active attitude corrections) to provide highly stable sensor-specific pointing.
An Asynchronous Linear Filter Architecture for Hybrid Event-Frame Cameras
We also demonstrate the integration of image convolution with linear spatial kernels Gaussian, Sobel, and Laplacian as an application of our architecture.
Constructive Equivariant Observer Design for Inertial Navigation
Inertial Navigation Systems (INS) are algorithms that fuse inertial measurements of angular velocity and specific acceleration with supplementary sensors including GNSS and magnetometers to estimate the position, velocity and attitude, or extended pose, of a vehicle.
Event Blob Tracking: An Asynchronous Real-Time Algorithm
Event-based cameras have become increasingly popular for tracking fast-moving objects due to their high temporal resolution, low latency, and high dynamic range.
GoferBot: A Visual Guided Human-Robot Collaborative Assembly System
It is composed of a visual servoing module that reaches and grasps assembly parts in an unstructured multi-instance and dynamic environment, an action recognition module that performs human action prediction for implicit communication, and a visual handover module that uses the perceptual understanding of human behaviour to produce an intuitive and efficient collaborative assembly experience.
Nonlinear constructive observer design for direct homography estimation
Feature-based homography estimation approaches rely on extensive image processing for feature extraction and matching, and do not adequately account for the information provided by the image.
Tracking control on homogeneous spaces: the Equivariant Regulator (EqR)
Accurate tracking of planned trajectories in the presence of perturbations is an important problem in control and robotics.
Equivariant Filters are Equivariant
Observers for systems with Lie group symmetries are an active area of research that is seeing significant impact in a number of practical domains, including aerospace, robotics, and mechatronics.
Equivariant Filter Design for Discrete-time systems
The kinematics of many nonlinear control systems, especially in the robotics field, admit a transitive Lie-group symmetry, which is useful in high performance observer design.
Constructive Equivariant Observer Design for Inertial Velocity-Aided Attitude
Inertial Velocity-Aided Attitude (VAA) is an important problem in the control of Remotely Piloted Aerial Systems (RPAS), and involves estimating the velocity and attitude of a vehicle using gyroscope, accelerometer, and inertial-frame velocity (e. g. GPS velocity) measurements.
A Linear Comb Filter for Event Flicker Removal
Event cameras are bio-inspired sensors that capture per-pixel asynchronous intensity change rather than the synchronous absolute intensity frames captured by a classical camera sensor.
Stereo Hybrid Event-Frame (SHEF) Cameras for 3D Perception
We provide a SHEF dataset targeted at evaluating disparity estimation algorithms and introduce a stereo disparity estimation algorithm that uses edge information extracted from the event stream correlated with the edge detected in the frame data.
Observer Design for Nonlinear Systems with Equivariance
The equivariant filter exploits the symmetry and respects the geometry of an equivariant system model and yields high performance robust filters for a wide range of mechatronic and navigation systems.
A Novel Passivity-Based Trajectory Tracking Control For Conservative Mechanical Systems
This potential is then used as the model to shape the energy of the true system such that its free solutions include the desired reference trajectory.
Equivariant filter (EqF): A general filter design for systems on homogeneous spaces
The kinematics of many mechanical systems encountered in robotics and other fields, such as single-bearing attitude estimation and SLAM, are naturally posed on homogeneous spaces: That is, their state lies in a smooth manifold equipped with a transitive Lie-group symmetry.
Equivariant Systems Theory and Observer Design for Second Order Kinematic Systems on Matrix Lie Groups
The state of a second order kinematic system on a matrix Lie group is naturally posed on the tangent bundle of the group with the inputs lying in the tangent of the tangent bundle known as the double tangent bundle.
Attitude Observation for Second Order Attitude Kinematics
This paper addresses the problem of estimating the attitude and angular velocity of a rigid object by exploiting its second order kinematic model.
Iterative Optimisation with an Innovation CNN for Pose Refinement
Object pose estimation from a single RGB image is a challenging problem due to variable lighting conditions and viewpoint changes.
Event Camera Calibration of Per-pixel Biased Contrast Threshold
Currently, most of the existing works use a single contrast threshold to estimate the intensity change of all pixels.
An Asynchronous Kalman Filter for Hybrid Event Cameras
Conversely, conventional image sensors measure absolute intensity of slowly changing scenes effectively but do poorly on high dynamic range or quickly changing scenes.
Equivariant Filter (EqF)
Simulation experiments of an example application show that the EqF significantly outperforms the extended Kalman filter and that the reduced linearisation error leads to a clear improvement in performance.
Shonan Rotation Averaging: Global Optimality by Surfing $SO(p)^n$
Shonan Rotation Averaging is a fast, simple, and elegant rotation averaging algorithm that is guaranteed to recover globally optimal solutions under mild assumptions on the measurement noise.
Robust Ego and Object 6-DoF Motion Estimation and Tracking
The problem of tracking self-motion as well as motion of objects in the scene using information from a camera is known as multi-body visual odometry and is a challenging task.
Constructive Observer Design for Visual Simultaneous Localisation and Mapping
Visual Simultaneous Localisation and Mapping (VSLAM) is a well-known problem in robotics with a large range of applications.
VDO-SLAM: A Visual Dynamic Object-aware SLAM System
Combining Simultaneous Localisation and Mapping (SLAM) estimation and dynamic scene modelling can highly benefit robot autonomy in dynamic environments.
Robotics
Reducing the Sim-to-Real Gap for Event Cameras
We present strategies for improving training data for event based CNNs that result in 20-40% boost in performance of existing state-of-the-art (SOTA) video reconstruction networks retrained with our method, and up to 15% for optic flow networks.
Ranked #3 on
Video Reconstruction
on MVSEC
Dynamic SLAM: The Need For Speed
In this paper, we propose a new feature-based, model-free, object-aware dynamic SLAM algorithm that exploits semantic segmentation to allow estimation of motion of rigid objects in a scene without the need to estimate the object poses or have any prior knowledge of their 3D models.
Robotics
CED: Color Event Camera Dataset
Event cameras are novel, bio-inspired visual sensors, whose pixels output asynchronous and independent timestamped spikes at local intensity changes, called 'events'.
Asynchronous Spatial Image Convolutions for Event Cameras
In this paper, we propose a method to compute the convolution of a linear spatial kernel with the output of an event camera.
Continuous-time Intensity Estimation Using Event Cameras
Event cameras provide asynchronous, data-driven measurements of local temporal contrast over a large dynamic range with extremely high temporal resolution.
3D tracking of water hazards with polarized stereo cameras
In this paper, we present a novel stereo-polarization system for detecting and tracking water hazards based on polarization and color variation of reflected light, with consideration of the effect of polarized light from sky as function of reflection and azimuth angles.
Feature-based Recursive Observer Design for Homography Estimation
This paper presents a new algorithm for online estimation of a sequence of homographies applicable to image sequences obtained from robotic vehicles equipped with vision sensors.
