Friday, August 3, 2018

Operation of Stepper Motor Instruction

Stepper motors operate differently from DC brush motors, which rotate when voltage is applied to their terminals. Stepper motors, on the other hand, effectively have multiple toothed electromagnets arranged around a central gear-shaped piece of iron. The electromagnets are energized by an external control circuit, for example a microcontroller.



To make the motor shaft turn, first one electromagnet is given power, which makes the gear’s teeth magnetically attracted to the electromagnet’s teeth. The point when the gear’s teeth are thus aligned to the first electromagnet, they are slightly offset from the next electromagnet. So when the next electromagnet is turned ON and the first is turned OFF, the gear rotates slightly to align with the next one and from there the process is repeated.

Stepper Motor Control by Varying Clock Pulses
Stepper motor control circuit is a simple and low-cost circuit, mainly used in low power applications. The circuit is shown in figure, which consist 555 timers IC as stable multi-vibrator. The frequency is calculated by using below given relationship:

The common point of the winding is connected to +12V DC supply, which is also connected to pin 9 of ULN2003. The color code used for the windings is may vary form make to make. When the power is switched on, the control signal connected to SET pin of the first flip-flop and CLR pins of the other three flip-flops goes active ‘low’ (because of the power-on-reset circuit formed by R1-C1 combination) to set the first flip-flop and reset the remaining three flip-flops. On reset, Q1 of IC3 goes ‘high’ while all other Q outputs go ‘low’. External reset can be activated by pressing the reset switch. By pressing the reset switch, you can stop the stepper motor. The motor again starts rotating in the same direction by releasing the reset switch.

Now you have got an idea about the types of super motors and its applications if you have any queries on this topic or on the electrical and electronic projects leave the comments below.

Saturday, May 27, 2017

Buyer's Guide to Selecting the Right Motor

Buyer's Guide to Selecting the Right Motor

Motors can be found practically everywhere. This guide will help you learn the basics of electric motors, available types and how to choose the correct motor. The basic questions to answer while deciding which motor is most appropriate for an application are which type should I choose and which specifications matter.
How do motors work?
Electric motors work by converting electrical energy to mechanical energy in order to create motion. Force is generated within the motor through the interaction between a magnetic field and winding alternating (AC) or direct (DC) current. As the strength of a current increases so does the strength of the magnetic field. Keep Ohm's law (V = I*R) in mind; voltage must increase in order to maintain the same current as resistance increases.

Electric Motors have an array of applications. Conventional industrial uses include blowers, machine and power tools, fans and pumps. Hobbyists generally use motors in smaller applications requiring movement such as robotics or modules with wheels.
Types of motors:
There are many types of DC motors, but the most common are brushed or brushless. There are also vibrating motors, stepper motors, and servo motors.

DC brush motors are one of the most simple and are found in many appliances, toys, and automobiles. They use contact brushes that connect with a commutator to alter current direction. They are inexpensive to produce and simple to control and have excellent torque at low speeds (measured in revolutions per minute or RPM). A few downsides are that they require constant maintenance to replace worn out brushes, have limited in speed due to brush heating, and can generate electromagnetic noise from brush arcing.

http://electrical-engineering-portal.com/5-steps-to-choose-best-motor-for-your-application

Micro and nano-motors for biomedical applications

PrĂ³tesis sobre implantes sin neAbstract

Micro- and nano-motors are a class of miniaturized man-made machines that are able to convert chemical or external energy into mechanical motion. The past decade has witnessed significant progress in the design and fabrication of micro- and nano-motors as a future intelligent and comprehensive biomedical platform. In this review we will critically assess the challenges and limitations of micro- and nano-motors, their mechanism of propulsion and applications in the biomedical field. Important insights into the future development and direction of nano-motors for improved biocompatibility and design will be discussed.
cesidad de medidas

Graphical abstract: Micro- and nano-motors for biomedical applications

This article is part of the themed collections: Emerging Investigators and 2014 Journal of Materials Chemistry B Hot Articles

Monday, February 20, 2017

What should you look for before purchasing handpiece?

What high-speed instruments are currently available on the market? What are the current trends in restoration and prosthetics and what future developments can be expected? The following sections provide information that will assist you in the fast and correct selection of the right dental handpieces for you.

Dental handpieces such as contra-angle handpieces and turbines are now viewed as more than simply “commodity products”. However, the information below makes it clear that this view is not adequate. Dental handpieces are among the most important tools for dentists and form an important part of every modern dental practice.


Air systems vs electrical systems
There are two systems for powering burs: air and electrical. In the air system a distinction is made between a turbine and an air motor.

In the air system a distinction is made between a turbine and an air motor. With turbines the bur is directly driven by a rotor. The rotor has an impeller powered by compressed air. Turbines reach an idle speed of up to 400,000 min-1. The working speed depends on the pressure exerted and is approximately half the idle speed - i.e. approx. 150,000 to 250,000 min-1. The maximum power of 10-26 W is also reached in this speed range.

The air motor drives the bur indirectly via a contra-angle handpiece or straight handpiece. It reaches a maximum speed of 25,000 min-1. Contra-angle handpieces are available in various step-up and step-down ratios. An air motor with a 2:1 contra-angle handpiece step-down ratio thus reaches a speed of approx. 12,500 min-1.

Electric motors reach an idle speed of up to 40,000 min-1. This corresponds to a bur speed of 200,000 min-1 for 1:5 contra-angle handpieces. The maximum power is over 60 W and the torque is approx. 3 Ncm. This means that electrically powered contra-angle handpieces are not slowed or stopped when the bur cuts through different tooth structures or prosthetic materials. They continue cutting at virtually constant speed regardless of the load. Compared to turbines, burs are much more stable with contra-angle handpieces. Burs in a contra-angle handpiece vibrate much less than with turbines. Improved stabilization means greater precision, faster work and less heating of the tooth substance during preparation.

The trend towards electric motors was first noticed in Europe. One important reason for this was the potential expense of installing new air lines in existing buildings. It also became obvious that electric drives are not only easier to install but are also more efficient in use. Now, some decades later, electric motors have become very popular in both Europe and Asia. Innovative developments in the fields of design, materials, torque and light are now also contributing to the popularity of electric motors in North America. They make work in the dental practice faster and easier.

The currently available range of straight and contra-angle handpieces includes the right instrument for every requirement. Most manufacturers offer products suitable for a wide range of applications and also products for highly specialized clinical applications.

Related Article:

http://www.im3vet.com.au/articles/HP-Vet-Dental-Low-Speed-Handpieces/287

Wednesday, February 1, 2017

Where To Find a Excellent Dentists?

A smile on a person’s face is one of the most noticeable things known to create a first and last impression on others. Let your smile be the signature of your personality even if you are not lucky enough to have extraordinarily sharp and adorable facial features. As Thich Nhat Hanh stated “Sometimes your joy is the source of your smile, but sometimes your smile can be the source of your joy”. So let your charming smile be a reason for the healthy joy that is best reflected with a pearly white shine of your teeth.

Things to look for to find a good dentist in your area

Experience – It is very important to consult a dentist who has several years of experience in the field of dentistry. The more the experience of a practitioner, the better are the chances to get clean and professional dental services.

Education – Look for an educated professional who is well-trained to carry on the dental procedures easily. It is also very important to look for someone, who is knowledgeable and stay informed with the ever changing dental technology and understands the novel approaches made to the technology.

Access to dental equipments – A good dentist must have access to all the latest tools required to carry on the dental procedures.

Sterilization – It is really important to ask for the sterilization process that a dentist makes use of. The best way is to look for the requirements for the sterilization procedures online and make your decision.

Reputation – Seek for a practitioner who holds a good reputation in your town. When it comes to reputation, it is important to research on the reviews other people have to give about their services. Speaking to friends, neighbors and family members will certainly help to let you know about the reputation of a dentist you are planning to see in the near future.

The other thing to think about is what the dentists primary goals are? Does he or she consult their patients on hwo to protect their teeth and what they can do to prevent cavities? Do they celebrate with you when you have gone another year without problems? Do they do whatever they can to help you prevent problems? Good dentists do not want you to have teeth problems and will be genuenly sorry when you do have issues that show up. So pay attention to their attitude toward dental issues or the lack of dental issues.

Last of all I would pay attention to the dentists prices for check-ups, major procedures, or other dental needs. Good dentists will not be looking to price gouge you but instead will try to work with you in getting you a good price. Dentists have to be able to cover their expenses but not in one fatal swoop. Dentists buy dental equipment like marathon micro motor  from internet.

These are just a few ideas I have on how to pick a good dentist but if you follow these steps you should have much better luck than my grandma did in picking a dentist that not only does great work but is also honest and fair in price.

Wednesday, January 25, 2017

ECO 1000 Brushless Micro Motor VS Marathon NR7 Micro Motor

ECO 1000 Brushless Micro Motor/ Induction
Very smooth running high powered high frequency
3 phase brushless induction motor.
With a system overload thus eliminating bad burn outs.
It comes complete with an induction hand drill, stand, cable, control box, mains cable and variable foot control. 1,000 – 50,000 rpm     Maximum torque: 7.8N cm
high performance brushless motor eliminates the need to change brushes
Ergonomically designed hand piece reduces fatigue in the operator’s hand
Self Diagnosis function to evaluate the unit and motor
Error code display is used to check status of the unit when trouble occurs
Marathon NR7 Micro Motor
We are offering an unbeatable deal on our new NR7 Micro motor and Control Unit.   This single-phase carbon brush motor with twist grip has a 2.35mm collet and comes complete with a variable bench and variable foot control and hand peice stand.   We are also offering a free tool kit and a free set of spare carbon brushes to all customers. 
See more:

Wednesday, January 18, 2017

Micro Motor control problems may be core issue for people with autism

If you’ve ever had an MRI scan, you know that it can be hard to lie still in the noisy, claustrophobic scanner. People often move involuntarily, requiring scientists to correct or eliminate the imaging data during movement.

Recently, a collaboration of Rutgers University and Columbia University researchers used this seemingly unhelpful data to further their understanding of a neurodevelopmental disease.

“We asked ourselves, ‘What could these involuntary movements, which researchers usually consider a nuisance, tell us about autism?’” Elizabeth Torres, PhD, an associate professor of cognitive psychology at Rutgers, said in a news release.

The neuroscientists analyzed functional magnetic resonance imaging (fMRI) data from 1048 participants, aged 6 to 50 years old, including individuals with autism spectrum disorders and healthy controls. The data was publicly available primarily through the Autism Brain Imaging Data Exchange databases.

The researchers determined that people with autism had more problems controlling their head movements than healthy controls. They also found that motor control problems were exacerbated with the presence of secondary neuropsychiatric diagnoses, lower verbal and performance intelligence and autism severity, as reported in a recent paper in Scientific Reports.

“For the first time, we can demonstrate unambiguously that motor issues are core issues that need to be included in the diagnosis criteria for autism,” Torres said in the release.

In addition, they found that psychotropic medications, commonly used to treat people on the autism spectrum, were associated with lower levels of motor control. These medications include anti-convulsants and anti-depressants. Autistic people who were taking more than one psychotropic medication moved the most during the fMRIs, and their movement worsened over the scanning session.

The researchers conclude in their paper, “Nevertheless, it remains to be demonstrated if changes in head micro-movements directly capture targeted changes in symptomology brought about by a specific medication.” Their findings are also complicated by the simultaneous presence of autism and other diseases, such as attention deficit hyperactivity disorder. So more research is needed.

Source:
http://scopeblog.stanford.edu/2016/12/28/motor-control-problems-may-be-core-issue-for-people-with-autism/