29 accepted papers
In this letter, we propose an Attention-Based Neural-Augmented Kalman Filter (AttenNKF) for state estimation in legged robots. Foot slip is a major source of estimation error: when slip occurs, kinematic measurements violate the no-slip assumption and inject bias during the update step. Our objectiv
We propose a emph{fully distributed} real-time model predictive control framework for transporting a single rigid object with multiple mobile manipulators. Each robot rapidly solves a local optimal control problem via Box-iLQR, while ADMM enforces consensus on the shared object state without central…
This paper presents an algorithm to improve state estimation for legged robots. Among existing model-based state estimation methods for legged robots, the contact-aided invariant extended Kalman filter defines the state on a Lie group to preserve invariance, thereby significantly accelerating conver
This letter presents a GPU-enabled parallel trajectory optimization framework for model predictive control (MPC) in complex urban environments. It fuses the advantages of sampling-based MPC, which can cope with nonconvex costmaps through random sampling of trajectories, with the advantages of gradie
This letter proposes a follower-stabilizing strategy for leader-waypoint-follower nonholonomic vehicle formation control. The follower-stabilizing strategy consists of the follower-stabilizing area and the follower's velocity correction term. When the follower crosses the waypoint generated by the l
Self-supervised multi-frame depth estimation achieves high accuracy by computing matching costs of pixel correspondences between adjacent frames, injecting geometric information into the network. These pixel-correspondence candidates are computed based on the relative pose estimates between the fram…
Recently, legged robots have been used for various purposes, such as exploring unknown terrain or interacting with the world. For control and planning legged systems during interactive operations, it is essential to estimate and respond to external forces. However, in legged system, it becomes diffi…
Recently, several 4D radar datasets have been published due to its high resolution and robustness in extreme weather conditions. However, most of the recent 4D radar dataset publications have insufficient odometry sensors, which is disadvantageous for 4D radar odometry research. To tackle this probl
Nonlinear model predictive control (NMPC) is an efficient and proven method for optimization-based autonomous vehicle motion planning. Among the various approaches, the iterative linear quadratic regulator, a differential dynamic programming variant, is a well-known efficient nonlinear optimization
We present a transcutaneous electrical nerve stimulation (TENS) based sensory feedback strategy to simultaneously transmit two senses through a single channel for giving force and position information of the gripper to the user. The two sensations were delivered by mixing two differently shaped curr
Information about the external wrench in legged robots is crucial for performing interactive tasks. However, most previous research has relied on attaching force/torque sensors to the end-effectors, which has disadvantages in terms of cost and maintenance. Therefore, this article presents a sensorle
Visual degradations caused by motion blur, raindrop, rain, snow, illumination, and fog deteriorate image quality and, subsequently, the performance of perception algorithms deployed in outdoor conditions. While degradation-specific image restoration techniques have been extensively studied, such alg…
Collision avoidance in emergency situations is a crucial and challenging task in motion planning for autonomous vehicles. Especially in the field of optimization-based planning using nonlinear model predictive control, many efforts to achieve real-time performance are still ongoing. Among various ap…
Semantic segmentation provides scene understanding capability by performing pixel-wise classification of objects within an image. However, the sensitivity of such algorithms towards domain changes requires fine-tuning using an annotated dataset for each novel domain, which is expensive to construct…
Amputees suffer from the weight, insufficient power, and uncomfortable control methods of their prostheses. Recent studies have introduced many ideas for both hardware and software to tackle these problems. In this letter, the authors introduce a preliminary platform of a robotic prosthetic hand sys
Vehicle Re-identification (Re-ID) aims to retrieve all instances of query vehicle images present in an image pool. However viewpoint, illumination, and occlusion variations along with subtle differences between two unique images pose a significant challenge towards achieving an effective system. In…
Input-output transmission ratio shifting mechanisms provide a variable transmission ratio, which effectively expands a speed-force operating range of actuators. Although it is the most effective solution to increase the performance of robotic systems, its application to compact robotic systems still…
Volumetric deep learning approach towards stereo matching aggregates a cost volume computed from input left and right images using 3D convolutions. Recent works showed that utilization of extracted image features and a spatially varying cost volume aggregation complements 3D convolutions. However, e…
Owing to the recent advances in the field of deep-learning-based approaches, state-of-the-art performance has been achieved for optical flow estimation. However, non-deep-learning-based improvement in the optical flow estimation performance is still required because many platforms, such as small UGV
Presence of haze in images obscures underlying information, which is undesirable in applications requiring accurate environment information. To recover such an image, a dehazing algorithm should localize and recover affected regions while ensuring consistency between recovered and its neighboring re…
Anchor boxes act as potential object localization candidates allow single-stage detectors to achieve real-time performance, at the cost of localization accuracy when compared to state-of-the-art two-stage detectors. Therefore, correct selection of the scale and aspect ratio associated with an anchor…
In this letter, we propose a 2-speed small transmission mechanism based on twisted string actuation (TSA). The proposed mechanism achieves a compact and simplified two-stage transmission ratio by adjusting the radius of the twisted string. This transmission mechanism does not require the complex mec
In this letter, we introduce an anthropomorphic robot hand by proposing a pneumatic dual-mode actuation mechanism powered by a compact pneumatic power generator based on the decomposition of hydrogen peroxide. Since the pneumatic power generator has limited gas supply ability for each fuel charge, a
In this letter, using the active dual-mode twisted string actuation (TSA) mechanism and tiny tension sensors on the tendon strings, an anthropomorphic robot hand is newly designed in a compact manner. Thanks to the active dual-mode TSA mechanism, which is a miniaturized transmission, the proposed ro
This paper presents a modified nonlinear pneumatic model for pneumatic force servo systems. The modified model is proposed in order to estimate pressures accurately for both chambers of a pneumatic cylinder by adopting flow coefficient maps, which is different from a conventional model whose flow co…
Electrotactile stimulation has been used to provide sensory information of forearm prosthesis to users. Although conventional sensory feedback method, where one electrode expresses sensory information of only one finger, could provide force information of three fingers by using three electrodes, it…
In this paper, a dual-mode twisting actuation mechanism with an active clutch is newly presented for a high performance tendon-driven robot (e.g., robot hand). This mechanism is a kind of mechanical automatic power transmission mechanism which provides fast motion and large contraction force by two…
When designing a lower-limb assisting robot with body-weight support (BWS), it is important to achieve high force fidelity to support body weight at standing phase. Low impedance operation at swing phase is also required not to disturb leg motions for users. The SoftGait is designed to achieve both…
In this paper, a method to extract the fingertip forces of the index and middle fingers from surface electromyography (sEMG) signals is studied by adopting the known common spatial pattern (CSP) approach. For unsupervised estimation of fingertip forces in real-time, CSP filtering is shown to be a no…