Oct 08, 2008
Contract design, development, and production of high-tech electronics is what Orchid Technologies Engineering and Consulting, Inc., is all about. The company combines capabilities in hardware and software engineering with the ability to perform detailed designs, construct prototype units, refine prototype designs, and manufacture the electronic product. With design capabilities ranging from subsystems to entire products, Orchid Technologies also provides design review and updates or corrections to existing designs.
�We do lots and lots of different designs, we've been working together as a team for over 10 years, and we bring a wealth of experience and know-how to the design process,� says Paul Nickelsberg, president and senior engineer at Orchid Technologies. �So we tend to be an advocate for our customers' and clients' design architectures. If they're not quite sure how to do things the best way electronically, we often know, from the gut, the right way to go, and to come up with some really neat architectures.�
One of the company's key strengths, according to Nickelsberg, is its ability to rescue a project in situations that might best be described as �design emergencies.�
�Many of our biggest successes have been designed in three months or less, from nothing to working prototypes,� he says. �And it's because of our experience and lean size that we can move mountains to get it done, whereas a larger company may have quite a bit of organizational red tape to cut through. We can come in and solve a problem like a laser beam, and it's a big reason why we're often hired.�
In one case, Orchid was approached by a major medical device company to take the reins of an electronics design project that had been in development for three years and was languishing due to a series of poor architectural choices by the client's original design team. The OEM was developing a cough-assist device to assist patients who, because of illness or infirmity, are unable to activate the musculature required to cause a cough. According to Nickelsberg, one of the major challenges was showing a certain amount of success quickly. After studying and re-evaluating the entire electronics design, Orchid made radical changes and delivered working prototype units in four months.
�This particular unit has a very special motor that develops, like a vacuum cleaner, the air pressure that's used in the cough process,� said Nickelsberg. �The motor is special because of its tiny size and because of the large amount of air that has to be moved in such a small space. So if you can imagine a vacuum cleaner motor 'on steroids,' that's the kind of motor we needed to design. It needed to be quiet, it needed to have a lot of power, and it needed to operate at a very low operating voltage while still providing very high pressure for a motor of its size. So that was no small feat, and, in particular, this motor was a 12V DC brushless motor with very, very low inductance.�
The high air pressure produced by the brushless DC motor, running at a maximum speed of 12,000 rpm, must be controlled with great accuracy throughout the cough-assist process. Airflow through the motor system changes rapidly, causing large, step-function changes in the motor's load. Motor control electronics, therefore, must quickly adjust to these rapid changes in motor load. Orchid's design includes a custom, high-efficiency DC motor controller that provides constant control of the motor's speed over a wide range of load conditions. Precise control of motor speed is achieved with advanced feed-forward control techniques.
�We needed to maintain constant pressure versus rpm,� said Nickelsberg. �We needed to do a special PID algorithm that actually controlled the constant pressure and the ability for us to set a motor rpm rate that was proportional to pressure output.�
Nickelsberg said that the motor's low inductance was necessary because, operating at only 12V and at very high rpm, it didn't leave much headroom to work with in the power design. �That makes a motor such as this very difficult to start and very difficult to commutate as a brushless motor,� he explained. �So very early on, we designed some special analog circuitry that could amplify these low signal levels on the windings and make it possible for us to start the motor in under 5 seconds. One of the failures of the other company was that it took them close to 60 seconds just to start the motor, which was unacceptable. When you push the �on� button, it should turn on. And a 60-second delay was just unacceptable.�
During the design process, the Orchid team realized how important the device would be to people in need of help with a bodily function that many take for granted. �We were very pleased to develop a coughing machine that would help individuals who suffer from Cystic Fibrosis, ALS, and other muscular diseases that prevent individuals from coughing on their own,� said Nickelsberg.
http://www.design2partmagazine.com/DeptArticle.asp
About Orchid Technologies
Orchid develops custom electronic products for OEM's. Orchid has successfully completed hundreds of electronic product designs. Orchid offers its clients a skillful blend of innovative hardware and software design with practical production expertise. Call Paul Nickelsberg, President and Senior Engineer at 978-461-2000X111 or email at info@orchid-tech.com
