scholarly journals Separate motor memories are formed when controlling different implicitly specified locations on a tool

2019 ◽  
Vol 121 (4) ◽  
pp. 1342-1351 ◽  
Author(s):  
Keaton Proud ◽  
James B. Heald ◽  
James N. Ingram ◽  
Jason P. Gallivan ◽  
Daniel M. Wolpert ◽  
...  
Keyword(s):  
Horizontal Plane ◽  
Applied Force ◽  
Control Points ◽  
Contextual Cues ◽  
Task Context ◽  
Object A ◽  
Task Goal ◽  
Straight Line ◽  
Left And Right ◽  
Straight Ahead

Skillful manipulation requires forming and recalling memories of the dynamics of objects linking applied force to motion. It has been assumed that such memories are associated with entire objects. However, we often control different locations on an object, and these locations may be associated with different dynamics. We have previously demonstrated that multiple memories can be formed when participants are explicitly instructed to control different visual points marked on an object. A key question is whether this novel finding generalizes to more natural situations in which control points are implicitly defined by the task. To answer this question, we used objects with no explicit control points and tasks designed to encourage the use of distinct implicit control points. Participants moved a handle, attached to a robotic interface, to control the position of a rectangular object (“eraser”) in the horizontal plane. Participants were required to move the eraser straight ahead to wipe away a column of dots (“dust”), located to either the left or right. We found that participants adapted to opposing dynamics when linked to the left and right dust locations, even though the movements required for these two contexts were the same. Control conditions showed this learning could not be accounted for by contextual cues or the fact that the task goal required moving in a straight line. These results suggest that people naturally control different locations on manipulated objects depending on the task context and that doing so affords the formation of separate motor memories. NEW & NOTEWORTHY Skilled manipulation requires forming motor memories of object dynamics, which have been assumed to be associated with entire objects. However, we recently demonstrated that people can form multiple memories when explicitly instructed to control different visual points on an object. In this article we show that this novel finding generalizes to more natural situations in which control points are implicitly defined by the task.

Impact of plumb location on the determination accuracy of chimney heeling by photographic method

2017 ◽  
Vol 919 (1) ◽  
pp. 55-59
Author(s):  
O.V. Raskatkina
Keyword(s):  
Image Processing ◽  
Experimental Research ◽  
Optimal Location ◽  
Paint System ◽  
Photographic Method ◽  
Round Shape ◽  
Straight Line ◽  
Left And Right

There is a method of using the corded plumb as vertical reference straight line, located in front of the objective of a digital photocamera in the article. When we take picture of the object under study, there will be this straight line in the photo, from which we can carry out all necessary measurements in the Paint system with the following conversion them into metric system. All possible variants of location of the reference straight line relative to it axis are considered by the example of the construction of the tower round shape and it is shown a method of heeling calculation by image processing results. Experimental research to determine the degree of influence of plumb location in the photo relative to it axe on the accuracy of the heeling determination was carried out by shooting the brick chimney with the 30 metres height when the plumb is located on the chimney axis and on different distance from the left and right of the axis. It is set in the result that the plumb location has influence on the accuracy of heeling determination. The optimal location is on the centre of the top section of the chimney and there is shown the method of accounting corrections due to inaccurate location.

Many-legged maneuverability: dynamics of turning in hexapods

1999 ◽  
Vol 202 (12) ◽  
pp. 1603-1623 ◽  
Author(s):  
D.L. Jindrich ◽  
R.J. Full
Keyword(s):  
Horizontal Plane ◽  
Center Of Mass ◽  
Vertical Plane ◽  
Force Production ◽  
The Body ◽  
Mean Velocity ◽  
Blaberus Discoidalis ◽  
Body Design ◽  
Reaction Forces ◽  
Straight Ahead

Remarkable similarities in the vertical plane of forward motion exist among diverse legged runners. The effect of differences in posture may be reflected instead in maneuverability occurring in the horizontal plane. The maneuver we selected was turning during rapid running by the cockroach Blaberus discoidalis, a sprawled-postured arthropod. Executing a turn successfully involves at least two requirements. The animal's mean heading (the direction of the mean velocity vector of the center of mass) must be deflected, and the animal's body must rotate to keep the body axis aligned with the heading. We used two-dimensional kinematics to estimate net forces and rotational torques, and a photoelastic technique to estimate single-leg ground-reaction forces during turning. Stride frequencies and duty factors did not differ among legs during turning. The inside legs ended their steps closer to the body than during straight-ahead running, suggesting that they contributed to turning the body. However, the inside legs did not contribute forces or torques to turning the body, but actively pushed against the turn. Legs farther from the center of rotation on the outside of the turn contributed the majority of force and torque impulse which caused the body to turn. The dynamics of turning could not be predicted from kinematic measurements alone. To interpret the single-leg forces observed during turning, we have developed a general model that relates leg force production and leg position to turning performance. The model predicts that all legs could turn the body. Front legs can contribute most effectively to turning by producing forces nearly perpendicular to the heading, whereas middle and hind legs must produce additional force parallel to the heading. The force production necessary to turn required only minor alterations in the force hexapods generate during dynamically stable, straight-ahead locomotion. A consideration of maneuverability in the horizontal plane revealed that a sprawled-postured, hexapodal body design may provide exceptional performance with simplified control.

Approximate Optimal Trajectories for Flexible-Link Manipulator Slewing Using Recursive Quadratic Programming

1993 ◽  
Vol 115 (3) ◽  
pp. 405-410 ◽  
Author(s):  
G. R. Eisler ◽  
R. D. Robinett ◽  
D. J. Segalman ◽  
J. D. Feddema
Keyword(s):  
Quadratic Programming ◽  
Horizontal Plane ◽  
Tracking Error ◽  
Flexible Manipulator ◽  
Joint System ◽  
Recursive Quadratic Programming ◽  
Straight Line ◽  
Tip Position ◽  
The Impact ◽  
Structural Mode

The method of recursive quadratic programming, coupled with a homotopy method, has been used to generate approximate minimum-time and minimum tracking-error tip trajectories for two-link flexible manipulator movements in the horizontal plane. The manipulator is modeled with an efficient finite-element scheme for a multi-link, multi-joint system with bending only in the horizontal-plane. Constraints on the trajectory include boundary conditions on link tip position, final joint velocities, accelerations and torque inputs to complete a rest-to-rest maneuver, straight-line tip tracking between boundary positions, and motor torque limits. Trajectory comparisons demonstrate the impact of torque input smoothness on structural mode excitation. Applied torques retain much of the qualitative character of rigid-body slewing motion with alterations for energy dissipation.

Contribution of auditory cortex to sound localization by the ferret (Mustela putorius)

1987 ◽  
Vol 57 (6) ◽  
pp. 1746-1766 ◽  
Author(s):  
G. L. Kavanagh ◽  
J. B. Kelly
Keyword(s):  
Auditory Cortex ◽  
Sound Localization ◽  
Horizontal Plane ◽  
Primary Auditory Cortex ◽  
Cortical Lesions ◽  
Mustela Putorius ◽  
Complete Destruction ◽  
Left And Right ◽  
The Right ◽  
Bilateral Lesions

Ferrets were tested in a semicircular apparatus to determine the effects of auditory cortical lesions on their ability to localize sounds in space. They were trained to initiate trials while facing forward in the apparatus, and sounds were presented from one of two loudspeakers located in the horizontal plane. Minimum audible angles were obtained for three different positions, viz., the left hemifield, with loudspeakers centered around -60 degrees azimuth; the right hemifield, with loudspeakers centered around +60 degrees azimuth; and the midline with loudspeakers centered around 0 degrees azimuth. Animals with large bilateral lesions had severe impairments in localizing a single click in the midline test. Following complete destruction of the auditory cortex performance was only marginally above the level expected by chance even at large angles of speaker separation. Severe impairments were also found in localization of single clicks in both left and right lateral fields. In contrast, bilateral lesions restricted to the primary auditory cortex resulted in minimal impairments in midline localization. The same lesions, however, produced severe impairments in localization of single clicks in both left and right lateral fields. Large unilateral lesions that destroyed auditory cortex in one hemisphere resulted in an inability to localize single clicks in the contralateral hemifield. In contrast, no impairments were found in the midline test or in the ipsilateral hemifield. Unilateral lesions of the primary auditory cortex resulted in severe contralateral field deficits equivalent to those seen following complete unilateral destruction of auditory cortex. No deficits were seen in either the midline or the ipsilateral tests.

Determination of Trackball and End Effector Diameters in Laparoscopic Tools

2005 ◽  
Vol 49 (18) ◽  
pp. 1710-1713
Author(s):  
A.E. Trejo ◽  
M.-C. Jung ◽  
M.S. Hallbeck
Keyword(s):  
Target Location ◽  
Target Position ◽  
Initial Position ◽  
End Effector ◽  
Independent Variables ◽  
Straight Line ◽  
Left And Right ◽  
Time Accuracy ◽  
Laparoscopic Tools

As part of a continuous effort of reaching the optimal use of the intuitool, a study was conducted to identify the optimal diameter combination between the trackball and the end effector ball. The task was to simulate the end effector movement during an operation, using different diameter combinations. Twenty students performed the trackball-controlling tasks to move the end effector from an initial position to designated circular-shaped targets. The trackball diameters were 19 mm and 40 mm, and those of the end effector balls were 3 mm, 5 mm, and 10 mm. There were four targets: right, left, up, and down. Travel time, accuracy, and trail deviation were measured as independent variables. Accuracy was not a significant factor showing that all participants followed instructions to reach each target as accurately as possible. The time to reach the target depended both on target location and trackball to end effector ratio individually and in their interaction. It was quickest to get to the upper target compared to all other locations. Trial deviation depended only on the target position and the target location and ratio interaction. The performance of going in a straight line was best for the left and right directions as opposed to up and down using the trackball.

scholarly journals Evaluating the relative contributions of copying and reconstruction processes in cultural transmission episodes

PLoS ONE ◽  
2021 ◽  
Vol 16 (9) ◽  
pp. e0256901
Author(s):  
James W. A. Strachan ◽  
Arianna Curioni ◽  
Merryn D. Constable ◽  
Günther Knoblich ◽  
Mathieu Charbonneau
Keyword(s):  
Cultural Transmission ◽  
Methodological Approach ◽  
Proof Of Concept ◽  
Cognitive Mechanisms ◽  
Contextual Cues ◽  
Task Context ◽  
Biological Mechanisms ◽  
Transmission Chain ◽  
Pragmatic Inference ◽  
The One

The ability to transmit information between individuals through social learning is a foundational component of cultural evolution. However, how this transmission occurs is still debated. On the one hand, the copying account draws parallels with biological mechanisms for genetic inheritance, arguing that learners copy what they observe and novel variations occur through random copying errors. On the other hand, the reconstruction account claims that, rather than directly copying behaviour, learners reconstruct the information that they believe to be most relevant on the basis of pragmatic inference, environmental and contextual cues. Distinguishing these two accounts empirically is difficult based on data from typical transmission chain studies because the predictions they generate frequently overlap. In this study we present a methodological approach that generates different predictions of these accounts by manipulating the task context between model and learner in a transmission episode. We then report an empirical proof-of-concept that applies this approach. The results show that, when a model introduces context-dependent embedded signals to their actions that are not intended to be transmitted, it is possible to empirically distinguish between competing predictions made by these two accounts. Our approach can therefore serve to understand the underlying cognitive mechanisms at play in cultural transmission and can make important contributions to the debate between preservative and reconstructive schools of thought.

scholarly journals A Mathematical Approach to Modeling Physics for the Vertical Position in Synchronized Swimming

2020 ◽  
Vol 9 (2) ◽  
Author(s):  
Devin Johnson ◽  
Benjamin Simonds
Keyword(s):  
Buoyancy Force ◽  
Applied Force ◽  
Upper Body ◽  
Vertical Position ◽  
Total Force ◽  
Surrounding Water ◽  
Straight Line ◽  
Synchronized Swimming ◽  
Buoyancy Forces ◽  
Order Polynomial

In Synchronized Swimming, arguably the most demanding sport known to man, one of the most basic positions is called a vertical. In this position a swimmer’s upper body is submerged in water and their legs are held above the surface while their body is kept in a straight line. Along with the buoyancy forces of the surrounding water and the air in the lungs, swimmers must also support themselves by making movements called sculls with their arms that propel them upwards. This additional force is the applied force. The goal of this research is to use physics principles to create a mathematical model that will help assist synchronized swimmers in maximizing their scores for the vertical position. The math done in this model confirmed that the amount of applied force inversely correlates with the buoyancy force needed to lift the synchronized swimmer out of the water. Additionally, the total force pushing the synchronized swimmer upwards is the same at each level. When the collected data is fitted to a second-order polynomial comparing applied sculling force to desired score, the graph shows that the data had an R2 fit of 0.984. This knowledge could ultimately inform athletes about how to use buoyancy and other forces to their advantage which could increase their performance levels.

Dynamic Modeling of an Independent Wheelset Bogie with MapleSim

2014 ◽  
Vol 1037 ◽  
pp. 71-74
Author(s):  
Tao Hua ◽  
Zheng Gang Lu
Keyword(s):  
Dynamic Analysis ◽  
Dynamic Characteristic ◽  
Dynamic Modeling ◽  
Analysis Tool ◽  
Rail Vehicles ◽  
Straight Line ◽  
Left And Right ◽  
Lateral Displacements

In order to help researchers better understand the dynamic characteristic of independent wheelset rail vehicles, this article presents a new modeling way to establish an independent wheelset bogie with a white-box dynamic analysis tool-MapleSim. In this article, an independent wheelset model is made firstly. Than based on this wheelset model, an independent wheelset bogie is made. After the modeling, the necessary validation with Simpack is done. The straight line dynamic validation includes the creepage of left and right wheels, the lateral displacements of bogie and both wheelsets’ yaw and lateral displacements. The results are similar to the model with the same parameters in Simpack which reveals that the bogie model in this article is correct and feasible.

LE CHOIX DE LA DIRECTION DES TRAJETS ENTRE FLEURS DES BOURDONS (BOMBUS) BUTINEURS

1997 ◽  
Vol 129 (5) ◽  
pp. 915-925 ◽  
Author(s):  
Catherine Plowright ◽  
Nathalie Cantin-Plante
Keyword(s):  
Laboratory Experiment ◽  
Decision Rule ◽  
Bumble Bees ◽  
The Other ◽  
Simple Rule ◽  
Future Research ◽  
Bumble Bee ◽  
Straight Line ◽  
Artificial Flowers ◽  
Straight Ahead

AbstractIn a laboratory experiment on the decision rule underlying the avoidance of flower revisitation by foraging bumble bees (Bombus impatiens), artificial flowers were arranged in two rows. For each flower visited, the choice was either to travel straight ahead onto a flower in the same row or to change direction and choose a flower in the other row. The distance between rows was manipulated to be smaller than, equal to, or greater than the distance between flowers in the same row. When the distances between adjacent flowers within a row and between rows were equal, a significant tendency to travel straight ahead was observed. This tendency was sensitive to changes in distance between rows, even when the distances between rows far exceeded the distance between flowers within a row. The tendency was abolished when the distance between rows was smaller than the distance between flowers within a row. A significant alternation of the bumble bee between rows (zigzag path) was observed in only one condition: when not only the distance between rows was much smaller than the distance between flowers in the same row, but also when the rows were staggered such that the bee could alternate between rows while still travelling in an almost straight line. These results show that the two variables of distance and angle are integrated, and that the choices made by bumble bees do not reflect a simple rule. Future research on tradeoffs is suggested.

scholarly journals From the Point Cloud to BIM Methodology for the Ideal Reconstruction of a Lost Bastion of the Cáceres Wall

2020 ◽  
Vol 10 (18) ◽  
pp. 6609
Author(s):  
Pablo Alejandro Cruz Franco ◽  
Adela Rueda Márquez de la Plata ◽  
Jesús Cruz Franco
Keyword(s):  
Remote Sensing ◽  
Point Cloud ◽  
Control Points ◽  
Non Invasive ◽  
Straight Line ◽  
Data Collection Process ◽  
Invasive Techniques ◽  
The City ◽  
Made In ◽  
The Ideal

Thanks to the use of non-invasive techniques and remote sensing in a 19th century building, it was possible to demonstrate that said building is a lost part of the Cáceres wall. This wall was believed to maintain the straight line from a known section, but remote sensing makes it clear that at that point the wall makes a break creating a door of which there was no record. Once this premise was confirmed, an ideal reconstruction hypothesis was developed. For this, the work base was taken on the data collected in an exhaustive data collection process, which launched millions of control points and facilitated in theorizing the original state of this lost section. The HBIM methodology greatly facilitated the process, and will allow for possible modifications with an IFC file as advances are made in that area. Finally, the research proposes an architectural project path that takes into account the data obtained remotely, and that achieves the inclusion of this part of the city in cultural interest and, of course, in a protected and cataloged area.

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