Look at these demos: Tear down embedded systems, get the point of linear motion control

Participate or watch in live embedded teardowns at an embedded systems event for a chance to win a Beagleboard kit. At IMTS last week, there was a potentially explosive demo on magnetorestrictive sensor technology, among other demonstrations. See photos. Link to tutorial and video videos.

By Control Engineering Staff September 15, 2008

Cary, NC, and Birmingham, UK – Participate or watch in live embedded teardowns at the Embedded Systems Show in England next month, and perhaps you can come away with a Beagleboard kit. Stateside, IMTS has been the site of a potentially explosive demo on magnetorestrictive sensor technology, among other demonstrations. See photos and link to videos from IMTS.

The MTS demo at IMTS, with an RMC controller from Delta Computer Systems and MTS Sensors’ Temposonics R-Series linear position sensor with SSI output, showed how dynamic linear actuators solve drive and transport tasks with high performance by using magnetostrictive technology in the measurement system.

This month MTS Systems Corp., Sensors Division demonstrated magnetostrictive sensor technology with a linear actuator demonstration at the 2008 International Manufacturing Technology Show in Chicago.

IMTS provides video on other demonstrations and advances from the show .

The MTS demo, with an RMC controller from Delta Computer Systems and MTS Sensors’ Temposonics R-Series linear position sensor with SSI output, showed how dynamic linear actuators solve drive and transport tasks with high performance by using magnetostrictive technology in the measurement system.

MTS explains how magnetorestriction works in a tutorial .

“The linear system converts energy from the rotary motor into linear motion using a linear actuator such as a belt-drive or ball screw,” said spokesperson Matt Hankinson. “By adding our absolute, linear position sensor on the output, we can compensate for mechanical transmission errors and disturbances at the load rather than relying on the rotary encoder on the motor.”

The Temposonics provides non-contact, absolute position feedback that is highly robust against shock, vibration and contamination. Such features make magnetostrictive sensor technology suitable for applications such as machine tools, cutting machines, handling and assembly robotics, or packaging machines. “Due to positioning accuracy, durability and reduced maintenance requirements,” said Hankinson, “the linear position measurement system improves the quality and efficiency of the production line.”

How the demo worked
The balloon demo on display at IMTS operated by allowing the user to move a dart on a carrier towards a balloon attached by a second carrier to a linear actuator system. As the dart approached the balloon, a position sensor for the balloon carrier enabled it to quickly move out of harm’s way. The position of both balloon and dart were updated every 0.5 milliseconds by an MTS R-Series SSI sensor with 1 micron resolution. Position feedback was provided to an RMC75E motion controller from Delta Computer Systems, which used a target generator in the position control loop to determine the desired trajectory for the balloon. The motion controller then sent a signal to the servo drive to command the desired position in the servomotor at a velocity of up to 10 feet per second.

The R-Series sensor with SSI output in the demo offered a resolution as low as one micron. With measuring rates up to 4 kHz and baud rates up to 1.0 MBd, the sensor ensured excellent performance in the linear system. The precise position control was enabled by a repeatability of 0.001% and linearity of 0.01% of the full stroke. A linearity of 20 microns independent of stroke length can be achieved if using the linearity correction option.

Another demo: linear motor, synchronous motion
Recently, a similar demo at the Hannover Fair featured a direct linear drive developed by EAAT GmbH (Chemnitz, Germany) and MTS Sensors’ Temposonics R-Series linear position sensor with SSI output. In that demo, a linear motor converted electrical energy directly into linear motion without mechanical linkages. The winding was fitted on a firmly mounted stator, while the considerably shorter magnetic conductor plate slid over the horizontal inductor. The speed curve of the traveling magnetic field and of the magnet plate was synchronous over a segmented length of 1,800 mm. Prior to selecting the MTS sensor for this linear motor, EAAT evaluated Temposonics in comparison to other manufacturers of magnetostrictive sensors. MTS sensors were chosen for the linear motor because they out-performed similar sensors in terms of reliability
and resistance to noise. Unlike other magnetic-based technologies, the performance of the MTS
magnetostrictive sensor was not impacted by interference from the linear motor.

The Embedded Systems Show 2008 will feature live teardowns of the Estes Micro-Tiger RC Helicopter and the X-Box Steering Wheel, as well as a Beagleboard development kit giveaway. The event takes place Oct. 1-2, 2008 at the NEC, Birmingham, UK.

Learn more about a Digi-Key Beagle Board .

Pre-registered conference delegates will have the opportunity to build and take home a fully configured embedded system based on the recently launched Beagleboard.
Live teardowns, introduced and made popular by exhibition organizer TechInsights , will offer visitors access to two of the latest popular consumer electronics gadgets. The Estes Micro-Tiger Helicopter is an indoor helicopter that uses Motion Automatic Sensing Controller (MASC) technology that allows beginners and experienced pilots to enjoy steering a helicopter with a tilt of the wrist. The wireless Microsoft Xbox 360 Steering Wheel simulates the resistance and force of driving, featuring dual rumble motors and realistic force feedback. By stripping away the cutting-edge toys into individual components, teardown experts will reveal techniques and technologies that bring the products to life.
A Build Your Own Embedded System (BYOES) program lets 50 preregistered visitors of the full conference take part in a hands-on educational experience at no charge, building and taking away their own embedded system, using the USB-powered Beagleboard. The program includes training courses for visitors to develop their system-building skills:
• Beagleboard 101 (a pre-conference workshop)
• Implementing a Web-based user interface
• Turn the Beagleboard in to a USB gadget (with Suspend/Resume)
• Using the OMAP DSP as a Linux co-processor
• Controlling a DC brushless motor with the Beagleboard
• Software Defined Radio with Beagle
• Teaching software with sugar and block diagrams
• Running Android on the Beagleboard
The highly integrated Beagleboard platform, released to the public in July, is based on an ARM-based microprocessor, the OMAP 3530 from Texas Instruments, and is bundled with a version of Linux from MontaVista.
“This year’s Embedded Systems Show is more focused than ever on the real-world applications of embedded systems and their place in the wider electronics market,” said exhibition director Andrew Porter. “The live-teardowns and the Build Your Own program will offer real hands-on experience and training, helping visitors develop their skills and expand their knowledge of the very latest techniques.”
–  Control Engineering News Desk
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