Classification of Cam Mechanisms
We can classify cam mechanisms by the modes of input/output motion, the configuration and arrangement of the follower, and the shape of the cam. We can also classify cams by…
Layout of plate cam profiles
· Drawing the displacement diagrams for the different kinds of the motions and the plate cam profiles for these different motions and different followers. · SHM, Uniform velocity, Uniform acceleration and retardation…
KINEMATICS OF CAM MECHANISMS CAMS
INTRODUCTION A cam is a mechanical device used to transmit motion to a follower by direct contact. The driver is called the cam and the driven member is called the…
Types of Kinematic Pairs
Kinematic pairs can be classified according to i) Nature of contact. ii) Nature of mechanical constraint. iii) Nature of relative motion. i) Kinematic pairs according to nature of contact: a) Lower Pair: A pair…
BASICS OF MECHANISMS
Introduction: Definitions : Link or Element, Pairing of Elements with degrees of freedom, Grubler’s criterion (without derivation), Kinematic chain, Mechanism, Mobility of Mechanism, Inversions, Machine. Kinematic Chains and Inversions: Kinematic…
Kinematic Inversions of 4-bar chain and slider crank chains
· Types of Kinematic Chain: 1) Four bar chain 2) Single slider chain 3) Double Slider chain · Four bar Chain: The chain has four links and it looks like a cycle frame…
Introduction to How to Provide Accurate and Robust Traffic Forecasts Practically?
With the development of our modern cities, growing traffic problems adversely affect people’s traveling convenience more and more, which has become one of the most crucial factors considered in urban planning and design in recent years. Urban traffic congestion is a severe problem that significantly reduces the quality of life in particularly metropolitan areas. However, frequently constructing new roads is not realistic and untenable in social and economic aspects. In the effort to deal with this intractable problem, so-called intelligent transportation systems (ITS) technologies are successfully implemented widely throughout the world nowadays. ITS with two important components advanced traffic management systems (ATMS) and advanced traveler information systems (ATIS) aim to relieve the increasing congestion and decrease travel time through providing information to the drivers by means of radio broadcasts or dynamic route guidance systems. The provision of accurate real-time information and predictions of traffic states such as traffic flow, travel time, occupancies, etc., is much fundamental and contributive to the great success of ITS (Chen et al., 2010; Dong et al., 2010; Vlahogianni et al., 2004; Lam et al., 2006; Tan et al., 2009; Tang et al., 2003; Thomas et al., 2010; Zhang & Liu, 2008, 2009c). As an important part of ITS, traffic states analysis and traffic forecasting are important in directing commuters to pick optimal routes, which have attracted many researchers to focus on this subject in recent decades. In general, as illustrated in the statement, the traffic forecasting…
Introduction to Active Traffic Management as a Tool for Addressing Traffic Congestion
Recurrent and non-ecurrent congestion in urban areas continues to be a major concern due to its adverse impacts on delays, fuel consumption and pollution, driver frustration, and traffic safety. In the U.S., limited public funding for roadway expansion and improvement projects, coupled with continued growth in travel along…
Introduction to Deploying Wireless Sensor Devices in Intelligent Transportation System Applications
A recent study by the UK Government’s Office of Science and Innovation, which examined how future intelligent infrastructure would evolve to support transportation over the next 50 years looked at a range of new technologies, systems and services that may emerge over that period (UK DfT, 2006). One key class of technology that was identified as having a significant role in delivering future intelligence to the transport sector was wireless sensor networks and in particular the fusion of fixed and mobile networks to help deliver a safe, sustainable and robust future transportation system based on the better collection of data, its processing and dissemination and the intelligent use of the data in a fully connected environment. The important innovations in wireless and digital electronics are beginning to support many applications in the areas of safety, environmental and emissions control, driving assistance, diagnostics and maintenance in the transport domain. The last few years have seen the emergence of many new technologies that can potentially have major impacts on Intelligent Transportation Systems (ITS) (Tully, 2006). U.S. DOT recently launched a 5 Years ITS strategic research plan to explore the potentially…
Introduction to Investigation of Measurement for Travel Time Variability
Congestion has grown over the past two decades making the travel time highly unreliable. The Federal Highway Administration (FHWA), US Department of Transportation (USDOT) indicated travel time as an important index to measure congestion. Frequent but stochastic, irregular delays increase the challenge for people to plan their journey – e.g. when to depart from the origin, which mode(s) and route(s) to use so the on-time arrival at the destination can be ensured. In addition to average travel time, the reliability of travel time has been deemed as an index for quantifying the effects of congestion, which can be applied to the areas of transportation system planning, management and operations as well as network modeling. Travel time reliability has been classified into two categories: probability of a non-failure over time and variability of travel time (Elefteriadou and Cui, 2005). The variability of travel time plays an important role in …
