SQUIGGLE motor general questions
Are your products RoHS compliant?
All New Scale Technologies motors, controllers, and ICs are
RoHS compliant.
Why should I use a SQUIGGLE
motor in my application?
SQL Series SQUIGGLE motors
are extremely small size linear micro motors that generate high
push force, fast motion and high resolution movements
(sub-micron) with very few parts. Compared to complex
electromagnetic gear-head motors with hundreds of parts,
SQUIGGLE micro motors allow product designers to add motion
features into products where they could not have been imagined
before. These simple, robust piezo motors are scalable to much
smaller sizes than electromagnetic motors, without significant
loss of power efficiency. This makes them ideal for portable
consumer products such as micro cameras and wearable
medical devices.
The SQ-100 Series SQUIGGLE
motors are usually used for nano-positioning in research labs,
semiconductor testing, and in manufacturing environments. SQ-100
SQUIGGLE motors offer higher resolution and push force than the
smaller SQL Series motors, and have travel ranges to 50 mm. They
are designed for easy integration into compact OEM instruments,
including laser systems, microscopes, and other scientific
instruments.
How does a SQUIGGLE motor
work?
 The
patented SQUIGGLE motor's structure (a nut) is excited at its
first mechanically resonant bending mode. Piezo material on
either side of the nut excites the X and Y bending modes in a
hula-hoop motion. The largest motion, only a few microns, occurs
at the middle and the ends of the tube. The areas in between,
where the least motion occurs, are referred to as the "node
points". By threading the center of the tube, a screw can be
inserted and the tiny vibrations, converted through friction
between the nut and the screw, cause the screw to rotate. By
changing the drive signals to vibrate the nut clockwise or
counter-clockwise, the direction of the screw rotation, and
resulting linear translation, is changed.
Note: the nut does NOT rotate, it only vibrates.
The screw does NOT vibrate, it only rotates and translates
linearly.
See also: SQUIGGLE
overview page for an animation of the SQUIGGLE motor in
action.
What is a piezo?
A piezo is a material exhibiting the piezoelectric effect. A
voltage applied across a piezoelectric material causes the
material to change shape. New Scale takes advantage of this
principle to drive its motors.
See also:
http://en.wikipedia.org/wiki/Piezoelectricity
How much torque does the SQUIGGLE
motor produce?
SQUIGGLE motors are linear motors and are specified for push
force, not for torque. The SQUIGGLE motor should not be used in
torque mode as with a typical rotary motor. New Scale has
extensive capabilities for designing custom motors with unique
capabilities and form factors and can design
custom rotary piezo
motors for specific customer applications. Please
contact our sales team with your
custom rotary motor requirement.
Can I use the SQUIGGLE motor like
a stepper motor?
The SQUIGGLE motor is not a stepper motor, but works by
vibration and friction. It takes 3-5 cycles at the motor's
resonant frequency to generate motion in the desired direction.
A single pulse will not be sufficient to drive the motor. Our
motor controllers and driver ICs can be given step-like commands
that run the motor for short open bursts. By integrating a
Tracker NSE-5310 position sensor (or other encoder), you can
make the SQUIGGLE motor "step" with 0.5 micron resolution and
hold its closed-loop position. This is a higher resolution than
most miniature stepper motors can achieve. Open-loop "steps" can
be even smaller but actual step size may vary depending on
loading.
What is the smallest "step" a
SQUIGGLE motor can take?
While the motor is not a stepper motor, it can be
driven to move in linear increments and it is sometimes
convenient to call these increments "steps."
(See also "Can I use the
SQUIGGLE motor like a stepper motor?")
Larger motors with larger screw diameter and finer
thread pitch can be driven to move in smaller
increments. For SQL motors,
the smallest guaranteed linear motion increment is <0.5 microns.
For SQ-100 series motors it is about 0.02 microns (20
nanometers).
Open loop step size will vary based on operating
conditions. For more precise control matching the
capabilities of the motor, an encoder with resolution at
or better than the motor should be used. For more information see the application notes "Creating
closed-loop motion systems using SQUIGGLE motors"
and "Choosing
position sensors for use with SQUIGGLE motors."
What length extension cable
can be used between the motor and controller?
Three-foot extension cables are available for the
SQUIGGLE
motor that connect the flex circuit on the motor to the driver
circuit board. Longer cables can be used, however:
- For direct (linear) drivers, longer
cables will add load capacitance to the driver, increasing
power usage. Do not exceed the drive circuit's load
capabilities. See driver
data sheets for details.
- For resonant drivers,
extra cable capacitance and resistance will affect motor
performance by de-tuning and damping the electrical
resonance. Keep added cable total capacitance below 100pF
and added resistance to a few ohms.
How do I drive a SQUIGGLE
motor?
A SQUIGGLE motor has two phases (perpendicular piezo plate
pairs) that must be driven 90 degrees out of phase at the
motor's mechanical resonant frequency. The electrical load of
the SQUIGGLE motor phases will look mostly like a capacitive
load to a drive circuit. The drive frequency, voltage, and
amount of capacitive load will vary by motor type. See
data sheets for details.
For lower voltage applications (SQL-RV-1.8 motors),
direct (linear) drivers are recommended as
the voltage can be controlled precisely.
For higher voltage applications (SQL-3.4 and SQ-100 series
motors),
resonant drivers are recommended
for higher voltage and higher efficiency.
Are there other ways
to drive SQUIGGLE motors besides your controllers?
We recommend using New Scale drive ASICs and
controllers, which have been designed to
provide optimal performance of SQUIGGLE motors. Schematics are
included in the manuals, and our custom engineering team can
help you integrate a SQUIGGLE drive circuit into your own
electronics boards.
How much power will the
SQUIGGLE motor use?
The motor is self-locking and requires no power to hold its position. Typical
power used by the motor while running will depend on the drive
method and controller used, as well as the input voltage, speed
and load. Use numbers from the
motor model pages or
product data sheets
when analyzing your power system maximum.
- SQL-RV-1.8 motor and MC-3300-RV controller: ~330 mW
- SQL-RV-1.8 motor and NSD-2101 drive IC: ~100 to
600 mW
- SQL-3.4 motor and MC-1100 or SQ-2300 controller:
~1 to 2.5 W
- SQ-100 series motor and MC-1100 or SQ-2300 controller:
1.5 W
Will the SQUIGGLE motor work in
high humidity, if wet, or underwater?
The SQUIGGLE motor will operate to specifications with a
non-condensing, relative humidity of 0 to 92 percent. Water or
moisture in direct contact with the motor screw will
significantly degrade motor performance and is not recommended.
Special housings and modifications can be made to SQUIGGLE
motors for applications requiring high humidity or wet
conditions. See our custom
engineering capabilities.
What is the operating
temperature range of the SQUIGGLE motor?
- SQL series motors are specified to work at -30 to +80°C
- SQ-100 series motors are specified to work at -20 to
+40°C
(We are always improving our products and specifications
are subject to change. Please refer to the
motor model pages or
product data sheets for the latest
specifications.)
Note: A cryogenic version of the SQUIGGLE motor is no
longer offered as a standard product. For custom cryogenic motor
development, please
contact us.
How long will a SQUIGGLE motor
last?
- SQL-1.8 motors are specified to operate for >1 million
cycles (back and forth full travel) at 15 grams load.
- SQL-3.4 motors are specified to operate for >70 thousand
cycles (back and forth full travel) at 100 grams load.
- SQ-100 series motors are not tested for lifetime.
(We are always improving our products and specifications
are subject to change. Please refer to the
motor model pages or
product data sheets for the latest
specifications.)
Will the motor work in vacuum,
ultra-high vacuum, or in space?
Vacuum and Ultra High Vacuum (UHV) motors are available. See
SQUIGGLE micro motors for lab and
vacuum.
What is the maximum load for a
SQUIGGLE motor?
Maximum load for a SQUIGGLE motor is specified as the "stall
force," or the limit below which all SQUIGGLE motors will move.
Some motors may in fact allow for higher forces than the rated
stall force. For best performance, load the SQUIGGLE motor to
half its specified stall force.
- SQL-RV-1.8 motors are rated at 50 grams force.
- SQL-3.4 motors are rated at 200 grams force.
(We are always improving our products and
specifications are subject to change. Please refer to
the motor model pages or
product data sheets for the latest
specifications.)
What is the best
load/performance for a SQUIGGLE motor?
The optimum performance (efficiency) of a SQUIGGLE motor is
achieved when it is run at half the specified stall force.
What is the mass of a SQUIGGLE motor?
(We are always improving our products and
specifications are subject to change. Please refer to
the motor model pages or
product data sheets for the latest
specifications.)
What is the SQUIGGLE motor's
resistance to shock and vibration?
SQL series SQUIGGLE motors are specified at 2500G shock
resistance. As the actual mass of the motor is so small, this
refers to the impact of the load on the motor.
How fast can I drive a SQUIGGLE
motor?
Speed depends on load. At the optimum motor drive frequency, with the full
voltage drive at 100% duty cycle, maximum speeds are:
- SQL-RV-1.8, >7 mm / second
- SQL-3.4, >4 mm/second
(We are always improving our products and
specifications are subject to change. Please refer to
the motor model pages or
product data sheets for the latest
specifications.)
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SQUIGGLE motor mounting and loading
How do I mount a SQUIGGLE motor?
Each SQUIGGLE motor is provided with housings that allow convenient mounting
while maintaining optimal motor performance.
See the design notes:
How
to mount the SQL-RV-1.8 piezoelectric SQUIGGLE motor
and
Quick tips for
integrating SQUIGGLE motors.
Do I need to provide a return force for a SQUIGGLE
motor?
A SQUIGGLE motor always needs an axial load on the
motor screw. The minimum recommended axial force varies
with motor type:
- SQL-1.8 Series: 5 grams
- SQL-3.4 Series: 10 grams
How do I properly apply a return force to a SQUIGGLE
motor?
For best performance the SQUIGGLE motor screw should
push along its axis, perpendicular to the surface to
be moved. Force can be applied by either end of the
screw. The perpendicular surface onto which the force is
applied should be a low friction surface such as Delrin.
A minimum return force on the screw should be maintained
at all times.
See the design note:
Quick tips for integrating SQUIGGLE motors.
Refer also to the SQUIGGLE motor
integration guides
(registration required) for reference designs and useful information about
continually applying a return force for the SQUIGGLE
motors.
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TRACKER NSE-5310 Position Sensor Questions
What is the resolution of the TRACKER NSE-5310?
Actual resolution of the of the TRACKER NSE-5310 is
the 2 mm pole pairs divided by the full 12 bit encoder
resolution.
Resolution = 2 mm / 4096 (12 bit) = 0.00048828125 mm
(0.48828125 microns).
Is there a max travel range of the TRACKER NSE-5310?
Travel range is essentially unlimited as the 2 mm
north-south pole pairs can be repeated indefinitely,
limited only by magnet manufacturing capabilities. To
retain the full specified accuracy, an extra 1.5 mm is
needed on each end of the magnet for over-travel.
How fast can I run the magnet over the TRACKER NSE-5310?
The TRACKER system is speed limited by the ability to
read the I2C bus fast enough without losing absolute
position data. For example, if reading position data,
and assuming a read at least every 1/4 pole pair to
determine position and direction, then the speed
limitation will be about 100 mm/s. Due to the I2C read
time delay, the position information will be delayed.
Also, full accuracy is achieved at lower speeds
depending on the fast/slow mode settings. See the
data sheet for more
details.
Is the TRACKER NSE-5310 affected by stray magnetic
fields?
Unlike Hall effect sensors, the TRACKER
self-compensates for external magnetic fields. It uses a
magnet strip with alternating north-south poles.
Internally, it averages across the 2 mm north-south
section of magnetic strip and will shift the internal
gain compensation value in the presence of stray fields
without losing position or accuracy.
How big is the TRACKER NSE-5310?
Various packaging options are available including
TSSOP-20 and chip on board (COB). Wafer-level chip scale
packaging as small as 3.9 x 2.5mm is available in
volume. See the data sheet
for details.
How do I integrate the TRACKER NSE-5310 into my system?
New Scale Technologies' web store offers convenient
demonstration kits which integrate the TRACKER NSE-5310
with a SQUIGGLE driver board. Detailed TRACKER NSE-5310
information can be found on the
TRACKER Overview
page and our manuals
download page (registration required).
How do I keep track of absolute position using the
TRACKER NSE-5310 after powering down?
There are a number of ways to use the TRACKER
position sensor and maintain absolute position. One of
the best ways is to look for the magnetic field to drop
off near the end of the magnet. The TRACKER will report
its internal gain compensation value (AGC) which can be
used to determine if the end of the magnet is near. The
user can then move back to the nearest pole pair
transition as their home reference position with the
full specified accuracy and repeatability.
Register to download
the application note for more details.
How do I attach a TRACKER NSE-5310 to an MC-1100 or
MC-3300?
Kits are available that include both a SQUIGGLE drive
board and TRACKER. If you bought a motor control board
separately and now want to integrate a TRACKER NSE-5310
position sensor, adapters are available that will allow
you to do this. Please
contact sales
for more information.
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Driver Questions
Which SQUIGGLE drive controller do I need to drive a
SQUIGGLE motor?
Evaluation packs which include a controller, motor
and all required cables are available on the
web store.
- For the SQL-RV-1.8 motor, use the MC-3300-RV SQUIGGLE
controller.
- For the SQL-3.4 motor, use the MC-1100-3.4 SQUIGGLE
controller.
- For a SQ-100 series motor, use the SQ-2300 controller.
How does a direct (linear)
drive SQUIGGLE drive work?
"Direct drive" refers to directly driving the
SQUIGGLE motor phases at the motor's mechanical resonant
frequency with two square waves 90 degrees out of phase.
By changing the leading phase, the motor's direction can
be changed. The amplitude of the square wave depends on
the motor.
For an SQL-RV-1.8 motor the amplitude can be up to 11
volts peak to peak, from 0 to 11 volts. This allows for
simple digital control from a micro-controller's PWM
peripheral, if available.
The NSD-2101 driver IC is a complete drive and
control circuit on a single chip. The MC-3300-RV SQUIGGLE
controller is provided with a microcontroller chip and
incorporates the NSD-2101 on a small daughter board to
demonstrate the control capabilities of the driver chip.
How does a resonant SQUIGGLE drive work?
A series resonant tank circuit is created by adding
an inductor to the output of the SQUIGGLE driver. The
electrical resonance of the tank circuit is "tuned" to
exactly match the SQUIGGLE motor's mechanical resonance.
In this way, high voltage drive signals can be applied
to the SQUIGGLE motor phases with much lower input
voltage and higher efficiency operation. Control and
drive techniques used for direct drive also apply to the
resonant drive method.
How do I control motor
speed?
The motor drive signal motor speed can be changed by
controlling the amplitude or duty cycle, or by pulse
width modulation.
- Voltage amplitude can be used to control motor
speed: Higher voltage results in higher speed.
- Duty cycle can be adjusted from 0% to 50% (max
speed). This works for either direct or linear drive
methods.
- Pulse width modulation (PWM) of the motor
drive signal (turning the motor drive on and off at
some frequency much lower than the motor drive
frequency) can also be used to control speed.
Shorter pulses result in slower speed.
What is the NSD-2101?
The NSD-2101 is a dedicated piezo motor driver ASIC
capable of driving an SQL-RV-1.8 Series SQUIGGLE motor
from a single 2.3 to 5.5 VDC supply. The NSD-2101 is a
linear drive IC and incorporates the motor signal
generation, speed, direction controls, voltage boost and
output drivers on a single chip. Input is via a standard I²C interface.
How many motors will the NSD-2101 drive?
The NSD-2101 can drive one SQL-RV-1.8 Series SQUIGGLE
motor.
What clock frequency should I provide to the NSD-2101?
SQUIGGLE motors work best at their optimum mechanical
resonance. A built-in oscillator in the NSD-2101
eliminates the need for an external master clock.
Patented frequency tracking keeps the drive signal at
the motor's optimum mechanical resonance.
Can I connect more I2C devices to the same bus as the
NSD-2101 or TRACKER NSE-5310 Position Sensor?
Yes. The NSD-2101 and TRACKER NSE-5310 are fully I2C
individually addressable and can run up to the 400 KHz
I2C bus rate. The TRACKER NSE-5310 also has 2 hardware
address selections to allow for 2 devices on the same
bus. See the
Philips I2C specification
(PDF) for limitations.
What is the operating voltage from the drive control
board to the SQUIGGLE motor?
- The SQL-RV-1.8 motor (with direct drive) operates at
2.3 to 11 volts peak to peak.
- The SQL-3.4 motor (with resonant drive) operates
between 50 and 100 volts peak to peak.
- The SQ-100 series motors (with
resonant drive)
operate between 75 and 150 volts peak to peak.
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New Scale Pathway Software
How will I know if there are updates to my software?
New Scale Technologies is always improving its
software and controller firmware. Pathway software
updates are available
here
(registration required).
Service and Support
What products does New Scale Technologies sell?
New Scale Technologies provides expertise in miniature
motion systems. Standard products include a range of
miniature SQUIGGLE motors, providing high linear forces
in very small form factors. Combining the SQUIGGLE
micro motors with equally tiny TRACKER linear magnetic sensors
and New Scale ASIC drive chip technologies results in
the smallest, highest resolution closed-loop motion
control systems available.
New Scale also provides custom linear and rotary
miniature piezo motor and controls design and
integration capabilities to achieve performance
unattainable with traditional electromagnetic motors and
actuators. We provide a full range of motor and module
design and support services from concept development
through production. We provide our motion control
expertise for the most demanding customers in fields
such as medical, consumer electronics, aerospace,
defense and security.
Contact us to discuss our
full line of standard miniature motion control solutions
or for your custom design and integration requirements.
Where do I buy a SQUIGGLE motor?
The easiest way to get a SQUIGGLE motor is to buy a
developer's kit from our
web store. If you need personal assistance please
contact sales@newscaletech.com.
What service and support does New Scale
Technologies provide?
New Scale Technologies offers help and advice to get you
up and running and supports customers through all stages
of product delivery, including specification,
integration, scale-up and production. We would be happy
to answer any questions you have at
sales@newscaletech.com.
What warranty does New Scale Technologies provide?
New Scale Technologies' standard warranty guarantees
its standard products against manufacturing defects for
1 year. For service and warranty related questions,
please contact
nstservice@newscaletech.com.
What design support can I get?
Our design services range from basic SQUIGGLE
integration support and design reviews, to design and
development of integrated systems for the smallest, most
efficient and cost effective use of the standard SQUIGGLE
technology, to extreme, custom piezo-based motor and
control solutions specifically optimized to meet the
most demanding requirements. We work with our OEMs at
all levels of development, from concept through
production.
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