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For vision controlled manipulation with a robotic arm, knowledge of the camera to end effector transformation is important. This is typically done by classical hand-eye calibration, where a transformation is estimated by observing a known calibration object under different robot poses. The same holds for mobile bases as well, where the mounted cameras' poses with respect to the robot need to be known...
Distortions, such as perspective distortion and partial occlusion, causes objects in different locations in the image of a scene appear to have different sizes. We present a new camera calibration method for estimating the dimension of objects, particularly people, in several locations in the image of a scene. Segmentation methods such as background subtraction combined with frame differencing is...
Machine vision has been widely and efficiently used for various industrial applications. However, in marine applications, this technology is still facing big challenges due to the free-swimming nature and unpredictable behavior of the fish. This paper presents new models for length estimation of small-size free-swimming fish objects using low-cost machine vision system. These models include two camera...
Recently, non-fixed camera-based free viewpoint sports video synthesis has become very popular. Camera calibration is an indispensable step in free viewpoint video synthesis, and the calibration has to be done frame by frame for a non-fixed camera. Thus, calibration speed is of great significance in real-time application. In this paper, a fast self-calibration method for a non-fixed camera is proposed...
Software cost and effort estimation is a necessary step in the software development lifecycle to track progress, manage resources, and negotiate. Though many accepted cost models exist, local calibration results in more accurate estimates. Locally calibrating Unified Code Count (UCC)’s dataset based on COCOMO (Constructive Cost Model)® II helped UCC’s development team learn which factors affected...
SAR Tomography processing by using multiple SAR images can create a 3-D image including the height distribution of scatterers. The height estimation can be realized assuming that the multi-baseline observation data as an array data in the DOA (direction of arrival) estimation methods. Orbit error in observation might cause DOA/height errors in imaging results; therefore, calibration of orbits or equivalent...
A method for 3D point source location estimation in single-sensor optical systems is presented. An axial coordinate is determined by means of estimating the defocus value of the point source. Planar 2D estimations are performed on a subpixel basis with magnification compensation. In order to compensate for the optical aberrations, an optical system model with 3D calibration procedure is presented...
This paper presents the framework for low-cost gaze estimation system to find the polynomial model used in with head pose based system. This framework uses three features - center of pupil, glint, and inner eye corner to create the polynomial model. The pupil-glint vector used to estimate eye gaze while glint-inner eye corner vector used to estimate head pose and adding inner eye corner to the model...
This paper presents a prototype of 14bit 80kSPS non-binary cyclic ADC without high accuracy analog components and complicated digital calibration. Since the redantancy of non-binary ADC tolerates the non-idealities such as capacitor mismatch and finite amplifier gain, the design consideration of this high accuracy ADC are be focused on the capacitance of sampling capacitor to satisfy the overall kT/C...
Calibration approach is widely used survey sampling that incorporates auxiliary information to increase the precision of survey estimates. In this manuscript, we propose two new calibration estimators of population mean in stratified sampling, using the known auxiliary information on mean and coefficient of variation in each stratum. A numerical example is presented to illustrate the application and...
The fusion of visual and inertial measurement has been popular in mobile robotics community for decades due to the complementary properties of two sensors. The combination of these two sensors offers rich texture of environment and accurate short-time motion prediction, making it particularly suitable for pose estimation, especially in GPS-denied unknown environment. In this paper, we propose a method...
3D LiDAR is widely used for mobile robots environment perception nowadays, which has high precision of distance measurement. In this paper, a calibration method which is suitable for Velodyne VLP-16 is firstly introduced. And then we utilize statistical filtering for isolated points removal. After statistical filtering, a slope location and orientation estimation method is presented based on PROSAC...
We have developed a wearable upper limb support system (ULSS) for support during heavy overhead tasks. The purpose of this study is to develop the voluntary motion support algorithm for the ULSS, and to confirm the effectiveness of the ULSS with the developed algorithm through dynamic evaluation experiments. The algorithm estimates the motor intention of the wearer based on a bioelectrical signal...
In this paper, we modify the classic manifold separation technique (MST), aiming to reduce its dependence on high signal-to-noise ratio (SNR) measuring environment. According to the analysis of the array response, it is demonstrated that to maintain a correct phase relationship between the received data at different calibration angles is indispensable for the application of MST. Thus, we slightly...
A new camera calibration approach is proposed that can utilize the affine transformations and surface normals of small spatial patches. Even though classical calibration algorithms use only point locations, images contain more information than simple 2D point coordinates. New methods are presented in this paper for the calibration problem with their closed-form solutions, then the estimated parameters...
In a video surveillance system with a single static camera, tracking results of moving persons can be effectively used for camera self-calibration. However, the current methods need to depend on robustness of both tracking and segmentation procedures. RANSAC has been widely used to remove outliers in finding the vertical vanishing point and the horizon line, but the performance is degraded when the...
Recently LiDAR-camera systems have rapidly emerged in many applications. The integration of laser range-finding technologies into existing vision systems enables a more comprehensive understanding of 3D structure of the environment. The advantage, however, relies on a good geometrical calibration between the LiDAR and the image sensors. In this paper we consider visual odometry, a discipline in computer...
Now-a-days, secure communication is a significant characteristic that should be proficient to accommodate increasing demand of wireless communication. The fundamental principle of secure communication is the extraction of secret key and keeping this secret. In this paper, we propose innovative approach for secret key extraction and reconciliation. We exploit channel reciprocity through relative calibration...
Time interleaving (TI) is one of the best approaches to relax the speed-power trade-off of analog-to-digital converters (ADC). However, channel mismatches especially timing can limit the resolution of TIADC if they are not addressed properly. To achieve an efficient calibration for these errors, the most difficult task is the error estimation in the digital domain. The correction is less problematic...
This paper proposes a gaze estimation algorithm using 3-D eyeball model and eyelid shape. The gaze estimation suffers from differences of eye shapes and individual behaviors, and requires user-specific gaze calibration. The proposed method exploits the usual 3-D eyeball model and shapes of the eyelid to estimate gaze without user-specific calibration and learning. Since the gaze is closely related...
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