scholarly journals Some Observations on Human Control of a Bicycle

2009 ◽  
Author(s):  
J. D. G. Kooijman ◽  
A. L. Schwab ◽  
Jason K. Moore
Keyword(s):  
Visual Observation ◽  
Upper Body ◽  
Lateral Motion ◽  
Forward Speed ◽  
Steering Control ◽  
Human Control ◽  
Control Actions ◽  
Knee Movement ◽  
Bicycle Rider ◽  
Pedaling Frequency

The purpose of this study is to identify human control actions in normal bicycling. The task under study is the stabilization of the mostly unstable lateral motion of the bicycle-rider system. This is done by visual observation of the rider and measuring the vehicle motions. The observations show that very little upper-body lean occurs and that stabilization is done by steering control actions only. However, at very low forward speed a second control is introduced to the system: knee movement. Moreover, all control actions are performed at the pedaling frequency, whilst the amplitude of the steering motion increases rapidly with decreasing forward speed.

Path Replanning Method for an AUV in Natural Hydrothermal Vent Fields: Toward 3D Imaging of a Hydrothermal Chimney

2014 ◽  
Vol 48 (3) ◽  
pp. 104-114 ◽  
Author(s):  
Yoshiki Sato ◽  
Toshihiro Maki ◽  
Ayaka Kume ◽  
Takumi Matsuda ◽  
Takashi Sakamaki ◽  
...  
Keyword(s):  
Hydrothermal Vent ◽  
Autonomous Underwater Vehicles ◽  
Visual Observation ◽  
Color Information ◽  
High Coverage ◽  
Human Control ◽  
Kagoshima Bay ◽  
Sufficient Energy ◽  
Shallow Seas ◽  
Limited Coverage

AbstractAutonomous underwater vehicles (AUVs) can operate without the need for human control or tether cables as long as there is sufficient energy. AUVs have recently been used for seafloor imaging. Visual observation by AUVs provides high-resolution color information of the seafloor. However, conventional observation techniques that follow a prespecified path offer limited coverage because it is impossible for operators to build a suitable path in unknown rough terrain. A flawed prespecified path will produce incomplete observation. If unobserved areas are found during postprocessing, another dive is necessary, which increases the total cost. To overcome this problem, the authors have proposed a path replanning method to realize high-coverage observation in one dive. With this method, the AUV evaluates unobserved areas after the first prespecified observation; if unobserved areas are found, the AUV recreates an appropriate path to cover what was missed. The validity of the proposed method was previously evaluated using an artificial target in a tank and in shallow seas at a depth of approximately 35 m. In this study, the feasibility of the method was validated in a more challenging setting: experimental data were taken from a hydrothermal vent field in Kagoshima Bay, Japan.

Who's in Control Here?

Philosophy ◽  
1976 ◽  
Vol 51 (198) ◽  
pp. 421-430
Author(s):  
Robert V. Hannaford
Keyword(s):  
Causal Explanation ◽  
Conceptual Scheme ◽  
Causal Account ◽  
Human Control ◽  
Voluntary Agency ◽  
Control Actions ◽  
The World ◽  
And Control

The question arises from recent arguments, including one by G. E. M. Anscombe, which hold that a belief in one's ability to choose one's actions is incompatible with a causal account of the world. For, if one's arguments deny either choice or causal sequences, how can one account for human control of actions? If to control one's actions means to work to cause some chosen end, and if either point of the argument were correct, how could anyone ever control one's actions at all? Yet we must be able to control actions if we are to seek out and select from evidence or develop any kind of conceptual scheme. I want to develop this necessity-of-control notion to show that arguments such as those advanced by Miss Anscombe are incoherent and to show that we must retain our notion of choice while giving a causal account of the world. I will argue that deterministic sequences and the notions of choice and control go together: in order for us to have a tenable explanation of the world we must be able to talk about choice and control and we must identify and use predictable deterministic sequences in our acting and choosing. I shall argue that we can retain both causal explanation and choice only by employing two different conceptions of causal agency: merely physical agency and the voluntary agency of embodied actors.

Throttle and brake pedals automation for populated areas

Robotica ◽  
2009 ◽  
Vol 28 (4) ◽  
pp. 509-516 ◽  
Author(s):  
E. Onieva ◽  
V. Milanés ◽  
C. González ◽  
T. de Pedro ◽  
J. Pérez ◽  
...  
Keyword(s):  
Artificial Intelligence ◽  
Fuzzy System ◽  
Speed Control ◽  
Trade Off ◽  
Traffic Lights ◽  
Human Control ◽  
Traffic Jams ◽  
Road Signs ◽  
Control Actions ◽  
Main Factor

SUMMARYArtificial intelligence techniques applied to control processes are particularly useful when the elements to be controlled are complex and can not be described by a linear model. A trade-off between performance and complexity is the main factor in the design of this kind of system. The use of fuzzy logic is specially indicated when trying to emulate such human control actions as driving a car. This paper presents a fuzzy system that cooperatively controls the throttle and brake pedals for automatic speed control up to 50km/h. It is thus appropriate for populated areas where driving involves constant speed changes, but within a range of low speeds because of traffic jams, road signs, traffic lights, etc. The system gets the current and desired speeds for the car and generates outputs to control the two pedals. It has been implemented in a real car, and tested in real road conditions, showing good speed control with smooth actions resulting in accelerations that are comfortable for the car's occupants.

scholarly journals Modeling and Control of an Active Stabilizing Assistant System for a Bicycle

Sensors ◽  
2019 ◽  
Vol 19 (2) ◽  
pp. 248 ◽  
Author(s):  
Chih-Keng Chen ◽  
Trung-Dung Chu ◽  
Xiao-Dong Zhang
Keyword(s):  
Dynamic Behavior ◽  
Degrees Of Freedom ◽  
Rear Seat ◽  
System Dynamic ◽  
Lagrange Equations ◽  
Modeling And Control ◽  
Control Actions ◽  
Bicycle Rider ◽  
Study Designs ◽  
And Control

This study designs and controls an active stabilizing assistant system (ASAS) for a bicycle. Using the gyroscopic effect of two spinning flywheels, the ASAS generates torques that assist the rider to stabilize the bicycle in various riding modes. Riding performance and the rider’s safety are improved. To simulate the system dynamic behavior, a model of a bicycle–rider system with the ASAS on the rear seat is developed. This model has 14 degrees of freedom and is derived using Lagrange equations. In order to evaluate the efficacy of the ASAS in interacting with the rider’s control actions, simulations of the bicycle–rider system with the ASAS are conducted. The results for the same rider for the bicycle with an ASAS and on a traditional bicycle are compared for various riding conditions. In three cases of simulation for different riding conditions, the bicycle with the proposed ASAS handles better, with fewer control actions being required than for a traditional bicycle.

Investigation of Riding Position Effects on Time-Trial Bicycle Drag Coefficient at Different Yaw Angles

2012 ◽  
Author(s):  
Peter N. Doval ◽  
Ilya V. Avdeev
Keyword(s):  
Aerodynamic Drag ◽  
Flow Direction ◽  
Time Trial ◽  
Frontal Area ◽  
Upper Body ◽  
Position Effects ◽  
System A ◽  
Program Star ◽  
Bicycle Racing ◽  
Bicycle Rider

Time-trial bicycle racing is highly influenced by aerodynamics, perhaps more so than any other form of bicycle racing. Companies competing in this class of racing spend millions of dollars trying to optimize the geometry of the bicycles and the gear each rider wears in order to reduce aerodynamic drag. The idea behind this project was to investigate other ways to optimize the aerodynamic efficiency of the rider, considering that the rider contributes the majority of the drag force of the bicycle-rider system. A large contributor to drag is the frontal area of the object of interest (a silhouette of the object in the fluid flow direction). This illustrates how much the rider’s body contributes to overall drag. If small riding adjustments could be made to the rider’s body during riding, drag may be significantly reduced. This idea and the fact that the direction of wind impacting the rider can vary influenced the concept of this project. It was hypothesized that adjusting the time-trial handlebars on the bicycle to place one of the rider’s hands further aft than the other would influence the upper body to rotate slightly. This could then reduce the frontal area of the rider in the wind direction, therefore reducing the aerodynamic drag. To simulate this situation, a non-contact 3-D digitizer was used to scan a rider aboard a bicycle in a normal riding position and in the above-mentioned, asymmetric position. This 3-D scan was then imported into the computational fluid dynamics (CFD) program Star-CCM+ and several simulations were run. Each of the two riding positions was simulated at differing yaw angles, ranging from −45° to 45°. The initial simulations seem to prove the theory as the asymmetrical riding position experiences decreased drag at significant yaw angles while the normal riding position does not. These results are encouraging and it is desired to continue refinement of the scanning and simulation methods as well as to validate these findings in a wind tunnel.

Permeability of the microcirculation in area postrema of rat

1988 ◽  
Vol 46 ◽  
pp. 348-349
Author(s):  
Shams M. Ghoneim ◽  
Frank M. Faraci ◽  
Gary L. Baumbach
Keyword(s):  
Brain Stem ◽  
Area Postrema ◽  
Upper Body ◽  
Sprague Dawley ◽  
Sodium Cacodylate ◽  
Acute Hypertension ◽  
Sprague Dawley Rats ◽  
Ultrastructural Characteristics ◽  
The Brain ◽  
Adjacent Brain

The area postrema is a circumventricular organ in the brain stem and is one of the regions in the brain that lacks a fully functional blood-brain barrier. Recently, we found that disruption of the microcirculation during acute hypertension is greater in area postrema than in the adjacent brain stem. In contrast, hyperosmolar disruption of the microcirculation is greater in brain stem. The objective of this study was to compare ultrastructural characteristics of the microcirculation in area postrema and adjacent brain stem.We studied 5 Sprague-Dawley rats. Horseradish peroxidase was injected intravenously and allowed to circulate for 1, 5 or 15 minutes. Following perfusion of the upper body with 2.25% glutaraldehyde in 0.1 M sodium cacodylate, the brain stem was removed, embedded in agar, and chopped into 50-70 μm sections with a TC-Sorvall tissue chopper. Sections of brain stem were incubated for 1 hour in a solution of 3,3' diaminobenzidine tetrahydrochloride (0.05%) in 0.05M Tris buffer with 1% H2O2.

Mid-aortic syndrome: computed tomography angiography depicting extensive collateral circulation in an 11-year-old patient with thoracoabdominal aortic coarctation

VASA ◽  
2012 ◽  
Vol 41 (2) ◽  
pp. 132-135 ◽  
Author(s):  
Krohn ◽  
Gebauer ◽  
Hübler ◽  
Beck
Keyword(s):  
Computed Tomography ◽  
Computed Tomography Angiography ◽  
Collateral Circulation ◽  
Intestinal Ischemia ◽  
Clinical Presentation ◽  
Lower Limbs ◽  
Upper Body ◽  
Descending Aorta ◽  
Before And After ◽  
Blood Pressures

The mid-aortic syndrome is an uncommon clinical condition characterized by severe narrowing of the descending aorta, usually with involvement of its renal and visceral branches, presenting with uncontrollably elevated blood pressures of the upper body, renal and cardiac failure, intestinal ischemia, encephalopathy symptoms and claudication of the lower limbs, although clinical presentation is variable. In this article we report the case of an eleven-year-old patient with the initial diagnosis of a mid-aortic syndrome and present the computed tomography angiography pictures and reconstructions before and after surgical therapy.

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