Thursday, April 1, 2010
เคลียดทำวิทยานิพนธ์
ผมเรียนปริญญาโทอยู่ที่ภาควิชาวิชาวิศวกกรมเครื่องกล มหหาวิทยาลัยเทคโนโลยีพระจอมเกล้าธนบุรีเป็นการศึกษาหาสมการการเคลื่อนที่ของหุ่นยนต์ปลา ซึ่งตอนแรกผมชอบอ่านและศึกษาเกี่ยวกับวิชาคณิตศาสตร์เป็นอย่างมากเพราะผมเชื่อว่ามันจะสามารถตอบคำถามเกี่ยวกับปัญหาของเราได้ แต่เมื่อศึกกษาไปเรื่อยๆก็เริ่มพบคำตอบว่าคณิศาสตร์เริ่มจะตอบปัญหาของเราไม่ได้ อันเนื่องจากว่าคณิตศาสตร์ที่มีอยูทุกวันนี้มันยังไม่สามารถที่จะอธิบายปรากฎการธรรมชาติที่มีอยู่ในโลกเราได้เลย ถึงอะธิบายได้ก็อะธิบายแบบผิวเผิน ยกตัวอย่างง่ายๆแค่จะอธิบายการเคลื่อนที่ของของไหลแต่ละอนุภาคนี้ก็ยังไม่สามารถอธิบายได้ ความหมายของผมคือ คุณไม่มีทางรู้เลยว่าเมื่อเวลาผ่านไปอนุภาคนี้เคลื่อนที่ไปอยู่ที่ไหนเมื่อเคลื่อนผ่านวัตถุรูปทรงหนึ่งๆ แต่คุณก็แค่สามารถประมาณโดยใช้วิธีการระเบียบเชิงตัวเลขโดยผ่าน navier stork ซึ่งจะมีรูปแบบสมการแบบอนุพันธ์หลายตัวแปรซึ่งคุณก็ไม่มีทางที่จะแก้มันด้วยวิธีการหาปริพันธ์ได้นอกจากวิธี Numerical อย่างเดียว ซึ่งคุณอจจะต้องมีโปรแกรมเพื่อมาแก้ปัญหา และคำตอบนั้นคุณก็ต้องไปเทียบกับผลการทดลองอยู่แต่เมื่อทำการทดลองคุณก็ได้แค่ตัวเลขมันออกมาซึ่งมันไม่สามารถย้อนกลับไปหาโมเดลได้ แล้วเราจะหาสมการการเคลื่อนที่ได้อย่างไร
Humanoid Robots
For all the attention they get, humanoid robots tend to be a pretty shallow bunch. Honda's Asimo dances, shakes hands, and occasionally serves tea. Toyota's series of Partner Robots can play musical instruments and guide visitors around one of the carmaker's facilities in Japan. A range of less famous models in labs around the world grab headlines by gripping objects without destroying them, or walking a few steps without tipping onto their extremely expensive heads. Humanoid bots are the celebrities of the robot world.
Which is why the unveiling this morning of Robonaut2—or R2—a collaboration between General Motor and NASA's Johnson Space Center, is such a milestone. R2 is the direct descendant of Robonaut, a humanoid model designed by NASA to assist astronauts during spacewalks (or extravehicular activities; EVAs, as the agency calls them), planetary exploration or any mission that could use an extra pair of dextrous hands. NASA intentionally avoided the complex, expensive business of two-legged mobility, instead fitting the robot with a single leg, designed to fit into the foot-restraints used by astronauts during EVAs. The robot could also be mounted, Centaur-like, on a wheeled platform. Robonaut never made it into space, but starting in 2007, General Motors embedded a team of their engineers with the existing Robonaut team at Johnson Space Center in Houston, to help design the robot's successor. GM also provided funding for the project, a move that, given NASA's current budgetary reshuffling, could be visionary in hindsight.
So why, exactly, would an embattled automaker devote its dwindling resources to a robot designed to clamber around spacecraft or motor across other planets? For the same reason GM has always been interested in robots: to build cars. "We had a common agenda with NASA," says Allen Taub, vice president of global research and development at GM. "They wanted to make a robot that could work next to an astronaut," he says. "The question we wanted to answer was, 'How do I make a robot so it can work with operators, without all of the safety precautions and cages?'" As they go through their automated routines, industrial assembly bots are inherently dangerous to be around. And according to Taub, installing cages and other safety measures often costs more than the robot itself. "This robot can be going through its paces, and if you just hold your hand up, it hits your hand and stops," he says.
On paper, that's not a new feature—NASA designed the original Robonaut to be controlled directly by a human, through teleoperation, or to follow various human-given commands, which the engineers called supervised autonomy. R2's engineers have focused more on that autonomy, but according to Robonaut2 project manager Myron Diftler, the advantage of working with GM was the company's experience with robots that can be used continuously, and by people without advanced degrees. "Their focus on durability and ease of use is different from NASA's," Diftler says. NASA robots are typically operated by highly-trained personnel, who issue various complex commands. And as robust as the Martian rovers appear to be, space-bound bots are designed to perform a given action hundreds of times. GM's experience with industrial robots helped the R2 team simplify the control interface—meaning less time and money spent on training, and less babysitting the bot by crew members in space or on Earth.
GM's goal in co-developing R2 is to eventually install similar systems in its plants, performing the kind of repetitive, ergonomically difficult jobs that might injure a human operator. Vision sensors in the robot's head, as well as pressure sensors in its fingers, allow it to manipulate parts with near-human precision. The biggest upgrades from the original Robonaut are R2's thumb, which now have four degrees of freedom (as opposed to three), and its overall speed, which have improved by a factor of four. One result of all of this engineering is the kind of breakthrough only a roboticist would swoon over: R2 can use both hands to work with a piece of flexible material. If that sounds simple, consider the amount of sensory data, cognitive processing and physical dexterity needed to manipulate something that flows and bends in your fingers. In the series of baby steps that comprises robotics, R2 is leaping.
Still, the two existing R2 prototypes are still essentially legless—GM has no need for a bipedal robot awkwardly swaying through its plants, and NASA plans to fit the robot with at least as many mobility platforms as its predecessor. R2's lower half is intended to be modular, and so is its redesigned head, which could fit a variety of sensor suites, depending on the mission or environment. Of course, until the agency's budget is sorted out, Diftler can't confirm what those missions will be, or when the robot could be deployed. Which means the robot, or some version of it, is more likely to show up in a GM plant before leaving the planet. Taub considers Robonaut2 a concept demonstration, analogous to what the company proved when its robotic Chevy Tahoe, Boss, won the DARPA Urban Challenge in 2007. As GM continues to work with NASA, Taub hopes to have a humanoid robot on the line at a pilot plant within 3 to 5 years (R2-related improvements, such as in vision processing, could make it to existing plants even faster). In fact, he sees a similar overall timeframe between autonomous driving and autonomous humanoid workers. The comparison is easy to make—GM provided the first glimpse of the robot chaffeur with Boss. Now, Robonaut2 could be the first blue-collar robot. Taub and Diftler also envision R2 being adapted for workplace environments where bulky protective gear limits human dexterity, such as clean rooms or nuclear facilities. Wherever it ends up, R2 represents a shot across the bow for the mechanized humanoid dilettantes at Honda and Toyota."The way we refer to it in the company, is that we've designed these robots to do work," Taub says. "Although it is fun and exciting, this is not show and tell."
Ref:www.robbotnews.com
Which is why the unveiling this morning of Robonaut2—or R2—a collaboration between General Motor and NASA's Johnson Space Center, is such a milestone. R2 is the direct descendant of Robonaut, a humanoid model designed by NASA to assist astronauts during spacewalks (or extravehicular activities; EVAs, as the agency calls them), planetary exploration or any mission that could use an extra pair of dextrous hands. NASA intentionally avoided the complex, expensive business of two-legged mobility, instead fitting the robot with a single leg, designed to fit into the foot-restraints used by astronauts during EVAs. The robot could also be mounted, Centaur-like, on a wheeled platform. Robonaut never made it into space, but starting in 2007, General Motors embedded a team of their engineers with the existing Robonaut team at Johnson Space Center in Houston, to help design the robot's successor. GM also provided funding for the project, a move that, given NASA's current budgetary reshuffling, could be visionary in hindsight.
So why, exactly, would an embattled automaker devote its dwindling resources to a robot designed to clamber around spacecraft or motor across other planets? For the same reason GM has always been interested in robots: to build cars. "We had a common agenda with NASA," says Allen Taub, vice president of global research and development at GM. "They wanted to make a robot that could work next to an astronaut," he says. "The question we wanted to answer was, 'How do I make a robot so it can work with operators, without all of the safety precautions and cages?'" As they go through their automated routines, industrial assembly bots are inherently dangerous to be around. And according to Taub, installing cages and other safety measures often costs more than the robot itself. "This robot can be going through its paces, and if you just hold your hand up, it hits your hand and stops," he says.
On paper, that's not a new feature—NASA designed the original Robonaut to be controlled directly by a human, through teleoperation, or to follow various human-given commands, which the engineers called supervised autonomy. R2's engineers have focused more on that autonomy, but according to Robonaut2 project manager Myron Diftler, the advantage of working with GM was the company's experience with robots that can be used continuously, and by people without advanced degrees. "Their focus on durability and ease of use is different from NASA's," Diftler says. NASA robots are typically operated by highly-trained personnel, who issue various complex commands. And as robust as the Martian rovers appear to be, space-bound bots are designed to perform a given action hundreds of times. GM's experience with industrial robots helped the R2 team simplify the control interface—meaning less time and money spent on training, and less babysitting the bot by crew members in space or on Earth.
GM's goal in co-developing R2 is to eventually install similar systems in its plants, performing the kind of repetitive, ergonomically difficult jobs that might injure a human operator. Vision sensors in the robot's head, as well as pressure sensors in its fingers, allow it to manipulate parts with near-human precision. The biggest upgrades from the original Robonaut are R2's thumb, which now have four degrees of freedom (as opposed to three), and its overall speed, which have improved by a factor of four. One result of all of this engineering is the kind of breakthrough only a roboticist would swoon over: R2 can use both hands to work with a piece of flexible material. If that sounds simple, consider the amount of sensory data, cognitive processing and physical dexterity needed to manipulate something that flows and bends in your fingers. In the series of baby steps that comprises robotics, R2 is leaping.
Still, the two existing R2 prototypes are still essentially legless—GM has no need for a bipedal robot awkwardly swaying through its plants, and NASA plans to fit the robot with at least as many mobility platforms as its predecessor. R2's lower half is intended to be modular, and so is its redesigned head, which could fit a variety of sensor suites, depending on the mission or environment. Of course, until the agency's budget is sorted out, Diftler can't confirm what those missions will be, or when the robot could be deployed. Which means the robot, or some version of it, is more likely to show up in a GM plant before leaving the planet. Taub considers Robonaut2 a concept demonstration, analogous to what the company proved when its robotic Chevy Tahoe, Boss, won the DARPA Urban Challenge in 2007. As GM continues to work with NASA, Taub hopes to have a humanoid robot on the line at a pilot plant within 3 to 5 years (R2-related improvements, such as in vision processing, could make it to existing plants even faster). In fact, he sees a similar overall timeframe between autonomous driving and autonomous humanoid workers. The comparison is easy to make—GM provided the first glimpse of the robot chaffeur with Boss. Now, Robonaut2 could be the first blue-collar robot. Taub and Diftler also envision R2 being adapted for workplace environments where bulky protective gear limits human dexterity, such as clean rooms or nuclear facilities. Wherever it ends up, R2 represents a shot across the bow for the mechanized humanoid dilettantes at Honda and Toyota."The way we refer to it in the company, is that we've designed these robots to do work," Taub says. "Although it is fun and exciting, this is not show and tell."
Ref:www.robbotnews.com
Data Acquisition - Product Reviews
Data Acquisition - Product Reviews
By Michael Russell
Generally data acquisition means to acquire data. However, in computer terminology, data acquisition is defined as the process of uniting real world data to produce the data to be maneuvered by the computer system. The data is in the form of waveforms or signals. These signals are obtained using different instruments and devices. The data acquired can be stored on the computer using vendor supplied software and the control can be made with the use of programming languages like Basic, Pascal, FORTRAN, C etc.
Data acquisition systems, as the name suggests are products or systems used to gather data or information from certain source. The data acquisition systems are distinguished on following basis: serial communication, USB, parallel ports and plug-in boards.
Without going much in depth, below are the details of different data acquisition boards.
Signatec PDA1000: This is the data acquisition product made by Signatec. The PDA100 is a 64-bit data acquisition board compatible with PCI device equipments. The "Plug and Play" feature is standard in all PCI devices. The analog bandwidth of DC to 500 MHz and digitization rate of up to 1 MHz makes it remarkably unique in its class. The bus that it uses is a Signatec Auxiliary Bus (SAB). This bus can allow data of 500 MB to be transferred per second. Multiple PDA1000 boards can be connected to the same PDA1000 DAQ board in the master-slave configuration through an interconnect port. It has six selectable signals ranging from 200 million volts to a maximum of 3.2 volts.
OME-PCI-1002 series: This data acquisition board is made by Omega. It features 12 bits 110 KHz analog to digital converter PCI board. The PCI board provides 32 single ended or 16 differential inputs along with 16 digital input and 16 digital output channels. This PCI board series provide sampling rate of 110 KS/s. However, it may vary within the series depending on whether the channels are single or multiple. Unlike many other company boards, the omega OME-PCI-1002 comes with software development kit compatible with Windows 98/NT/2000/XP. This software development kit includes DLL files for high level programming languages and OCX files for Active X programming.
iOTech DaqBoard-3000 series: This is a multifunction data acquisition board embedded with four 1 MHz PCI boards. Unlike OME-PCI-1002 board, this board has 16 single-ended or 8 differential analog inputs with the option to expand them up to 64 single-ended or 32 differential analog inputs. DaqBoard-3000 series has 24 high-speed digital I/O lines. There are four 32 bit counter input channels with quadrature encoder capability. It supports multiple DMA channels and USB version of this board is also available in market.
Advantech PCI-1670: This is a high performance PCI board with GBIB interface. PCI-1670 board works fully with IEEE 488.1 and 488.2 standards. It has full functionality with windows 95/98/NT/2000/XP and MS-DOS operating systems. The "Plug and Play" feature automatically assigns I/O address and provides powerful and easy to use configuration utility. It also has full support for drivers and libraries of C/C++, C++ Builder, Visual Basic and Labview.
Michael Russell
Your Independent guide to Data Acquisition [http://data-acquisition-guided.com]
Article Source: http://EzineArticles.com/?expert=Michael_Russell
http://EzineArticles.com/?Data-Acquisition---Product-Reviews&id=467534
By Michael Russell
Generally data acquisition means to acquire data. However, in computer terminology, data acquisition is defined as the process of uniting real world data to produce the data to be maneuvered by the computer system. The data is in the form of waveforms or signals. These signals are obtained using different instruments and devices. The data acquired can be stored on the computer using vendor supplied software and the control can be made with the use of programming languages like Basic, Pascal, FORTRAN, C etc.
Data acquisition systems, as the name suggests are products or systems used to gather data or information from certain source. The data acquisition systems are distinguished on following basis: serial communication, USB, parallel ports and plug-in boards.
Without going much in depth, below are the details of different data acquisition boards.
Signatec PDA1000: This is the data acquisition product made by Signatec. The PDA100 is a 64-bit data acquisition board compatible with PCI device equipments. The "Plug and Play" feature is standard in all PCI devices. The analog bandwidth of DC to 500 MHz and digitization rate of up to 1 MHz makes it remarkably unique in its class. The bus that it uses is a Signatec Auxiliary Bus (SAB). This bus can allow data of 500 MB to be transferred per second. Multiple PDA1000 boards can be connected to the same PDA1000 DAQ board in the master-slave configuration through an interconnect port. It has six selectable signals ranging from 200 million volts to a maximum of 3.2 volts.
OME-PCI-1002 series: This data acquisition board is made by Omega. It features 12 bits 110 KHz analog to digital converter PCI board. The PCI board provides 32 single ended or 16 differential inputs along with 16 digital input and 16 digital output channels. This PCI board series provide sampling rate of 110 KS/s. However, it may vary within the series depending on whether the channels are single or multiple. Unlike many other company boards, the omega OME-PCI-1002 comes with software development kit compatible with Windows 98/NT/2000/XP. This software development kit includes DLL files for high level programming languages and OCX files for Active X programming.
iOTech DaqBoard-3000 series: This is a multifunction data acquisition board embedded with four 1 MHz PCI boards. Unlike OME-PCI-1002 board, this board has 16 single-ended or 8 differential analog inputs with the option to expand them up to 64 single-ended or 32 differential analog inputs. DaqBoard-3000 series has 24 high-speed digital I/O lines. There are four 32 bit counter input channels with quadrature encoder capability. It supports multiple DMA channels and USB version of this board is also available in market.
Advantech PCI-1670: This is a high performance PCI board with GBIB interface. PCI-1670 board works fully with IEEE 488.1 and 488.2 standards. It has full functionality with windows 95/98/NT/2000/XP and MS-DOS operating systems. The "Plug and Play" feature automatically assigns I/O address and provides powerful and easy to use configuration utility. It also has full support for drivers and libraries of C/C++, C++ Builder, Visual Basic and Labview.
Michael Russell
Your Independent guide to Data Acquisition [http://data-acquisition-guided.com]
Article Source: http://EzineArticles.com/?expert=Michael_Russell
http://EzineArticles.com/?Data-Acquisition---Product-Reviews&id=467534
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