Search results

Industrial robots are traditionally programmed using only the internal joint position sensors, in a sense leaving the robot blind and numb. Using external sensors, such as cameras and force sensors, allows the robot to detect the existence and position of objects in an unstructured environment, and to handle contact situations not possible using only position control. This thesis presents work on

Force sensing provides robots the capability to accomplish tasks where physical interaction with the environment is required, such as assembly. Small position uncertainties can then be corrected for by sensing the contact forces. This thesis considers the problem of force-controlled assembly, including how tasks can be specified in a simple and intuitive way and how robust task execution under unc

We study the realizability and strong satisfiability problems for SAFETY LTL, a syntactic fragment of Linear Temporal Logic ([Formula presented]) capturing safe formulas. While it is well-known that realizability for this fragment lies in [Formula presented], the best-known lower bound is [Formula presented]-hardness. Surprisingly, closing this gap has proven an elusive task. Previous works have c

Perceiving and understanding human motion is a fundamental problem in computer vision, with diverse applications encompassing sports analytics, healthcare monitoring, entertainment, and intelligent interactive systems. Multi-camera systems, by capturing multiple viewpoints simultaneously, enable robust tracking and reconstruction of human poses in 3D, overcoming limitations of single-view approach

To solve the problem of fatigue of the UAV operator during long-term search and reconnaissance missions, a research hardware and software complex was created, in which the positioning of the auxiliary UAV video camera with a narrow field of view is carried out. Dynamixel Library for MATLAB and Simulink was used to organize the interaction of actuators with the virtual environment, which allows com

Extremely thinned layers and possible folding make the dating of the deepest sections of ice cores especially challenging. Cosmogenic radionuclides have the potential to provide independent age estimates. The 36Cl/10Be ratio is largely independent of production rate changes that affect individual radionuclides and has an effective half-life of 384 kyr, making it an ideal tool for dating the new 1.

During the Last Glacial Period (LGP), Greenland experienced approximately 30 abrupt warming phases, known as Dansgaard-Oeschger (D-O) events, followed by cooling back to baseline glacial conditions. Studies of mean climate change across warming transitions reveal indistinguishable phase offsets between shifts in temperature, dust, sea salt, accumulation, and moisture source, thus preventing a comp

One of the most challenging problems in paleoclimate research is how orbital cyclicities forced Earth’s climate variations during the late Quaternary. To address this issue, we investigated the differences in silicate weathering, a sensitive climate indicator, at different latitudes on orbital timescales by examining geochemical and clay mineral data from the mid-latitude Sea of Okhotsk and integr

In this paper, we present a framework to identify discrete-time, single-input/single-output, switched linear systems (SISO-SLSs) from input–output data measurements. Continuous state is not assumed to be measured. The key step is a deadbeat observer-based transformation of the SLS model to a switched auto-regressive with exogenous input (SARX) model. Discrete states are estimated by a three-stage

Semantic memory access has been characterized as abnormal in schizophrenia, but findings concerning automatic spreading activation at short stimulus onset asynchronies (SOA) have been inconsistent. Using the N400 as an indicator of semantic priming, a recent study (Mathalon, Faustman, & Ford, 2002) found evidence of hyperpriming in schizophrenic patients in a picture verification task. The pre

Autonomous vehicles allow utilisation of new optimal driving approaches that increase vehicle safety by combining optimal all-wheel braking and steering even at the limit of tyre–road friction. One important case is an avoidance manoeuvre that, in previous research, for example, has been approached by different optimisation formulations. An avoidance manoeuvre is typically composed of an evasive p

Distributed surveillance systems typically consist of multiple cameras that need to store some fraction of their video streams at a central storage node. The disk space of this node constitutes a shared resource. In the paper the disk space allocation is formulated as a PI control problem and a new method for enforcing global resource constraints inspired by anti-windup tracking is proposed. The a

One of the most significant obstacles for the every­day use of systems based on Brain­Computer Inter­faces (BCIs) is the tediousness of calibration. Successful improvements on calibration, particularly the time needed and the user­experience, have been made with, e.g., transfer learning, gamification, and task estimation [1, 2, 3]. Inthis work, we present an adaptive approach to BCI systems’ calib

This paper presents an LO frequency multiplier and phase shifter for the 28-GHz band, implemented in 28nm FD-SOI CMOS technology. The phase control is introduced in an injection-locked oscillator, followed by an injection-locked frequency tripler. The phase of the output signal is compared with that of the input signal using a phase detector based on third harmonic mixing, enabling automatic phase

Past efforts to synthesize and quantify the magnitude and change in carbon dioxide (CO2) fluxes in terrestrial ecosystems across the rapidly warming Arctic-boreal zone (ABZ) have provided valuable information but were limited in their geographical and temporal coverage. Furthermore, these efforts have been based on data aggregated over varying time periods, often with only minimal site ancillary d

Southeast Asia is a region known for active land-use changes (LUC) over the past 60 years; yet, how trends in net CO2 uptake and release resulting from LUC activities (net LUC flux) have changed through past decades remains uncertain. The level of uncertainty in net LUC flux from process-based models is so high that it cannot be concluded that newer estimates are necessarily more reliable than old

Cell-free Massive MIMO systems consist of a large number of geographically distributed access points (APs) that serve the users by coherent joint transmission. The spectral efficiency (SE) achieved by each user depends on the power allocation: which APs that transmit to which users and with what power. In this article, we revisit the max-min and sum-SE power allocation policies, which have previou

Cell-free massive MIMO systems consist of many distributed access points with simple components that jointly serve the users. In millimeter wave bands, only a limited set of predetermined beams can be supported. In a network that consolidates these technologies, downlink analog beam selection stands as a challenging task for the network sum-rate maximization. Low-cost digital filters can improve t