Trajectory Generation
Aerotech’s trajectory generator distributes the computation
across the axes yielding more time for user programs to
execute. The position, velocity, and acceleration are
calculated and streamed to the axis controller every 125 μs.
Each new trajectory can be velocity blended or set a new
endpoint for the motion. At the lowest level of trajectory
generation a seven segment acceleration profile can be
employed to precisely control the acceleration/deceleration
of each move, even asymmetrically if necessary. Advanced
trajectory commands, such as the slice command, increase the
machine throughput and ease programming by optimally
blending a step and scan into a single contoured move.
Traditional soft-limits and safe zones are adhered to by the
generator.
For users that prefer graphical programming, Aerotech’s
Motion Designer can be used to build any trajectory from
basic building blocks – trapezoidal, sinusoidal, triangle, etc.– or just import actual data. Motion Designer will calculate the
missing state information, filters can be added to smooth
noise, and a program will be auto-generated and compiled
that will run on any Aerotech controller.
Software
Aerotech’s Motion Composer Suite for the Aerotech A3200,
Ensemble, and Soloist controllers focuses on ease-of-use for
the user. Many of the common configurations are set up
through calculators. The programmer will shorten
development times compared with other controllers due to the
Integrated Development Environment (IDE) that includes all of
the standard and advanced tools for setup and debug.
Additionally, Aerotech provides the flexibility to use the tools
or controller most familiar to programmers. Complementing
the IDE is a comprehensive .NET motion library that provides
classes for motion, I/O, status, and diagnostic information. A
programmer can program in Visual Studio and use the .NET
library, or use the Motion Composer (IDE) to develop code
with English style commands or G-code. A LabVIEW® .vi
library is available for NI users. And for those using VB6,
C++, or C, a complete C library and ASCII interface is
available. The Motion Composer Suite includes the Motion
Composer IDE, Digital Scope with many tools for time and
frequency analysis, Configuration Manager for parameter
and fault setting, Status Utility, and Operator’s Interface. The
Digital Scope collects and displays any signal in the
controller. This provides users the tools to examine motion,
inputs, and outputs of the process to optimize motion. Tools for time series analysis (autotuning, min, max, rms) and frequency
analysis (FFT, loop transmissions, bode plots) make setup
easy. For instance, adding up to eight filters can be done by
dragging the gain curve on a bode plot to the desired
response. The filters will be automatically calculated and
loaded into memory to achieve the goal. The integrated tools
enable achieving optimal high performance nanomotion fast
and easy.
System Test and Metrology Capabilities
In order to achieve, measure, and certify the stated
specification of the selected system, Aerotech made large
investments over the years in its metrology and cleanroom
capabilities. Our cleanroom not only meets the requirements
of large system ISO 14644-1 Class 6 (Federal Standard
209E Class 1000) and cell specific ISO Class 5 (Class 100)
capabilities, but also contains seismically isolated test areas
that are temperature controlled to better than 0.25°C. When
system test specifications do not require cleanroom capability,
our other metrology laboratories (see
http://www.aerotech.com/clroom.html) are utilized. These
laboratories also have the capabilities to meet the
environmental metrology requirements of nanotechnology and
beyond.
To complement this large investment in our facilities, Aerotech
also invested heavily in the required test equipment. State-of-the-art interferometers from Agilent, Renishaw and Zygo,
phase measuring interferometers, capacitive position sensors,
and LVDT transducers are used to verify, calibrate, and tune
all of our linear systems.
For angular and geometrical measurement of rotary
equipment, Moeller Wedel auto collimators combined with
our Advanced Rotary Test Measurement System verify
accuracy, resolution, axial and radial error motion and tilt
error motion. This primary test system is supplemented by a
host of other instrumentation: phase measuring interferometers,
capacitance gages, LVDT transducers, optical flats, etc.
Dynamic Calibration Management System
In order to achieve the highest possible system accuracy from
our multi-axis nanopositioning systems, Aerotech has
developed an industry-leading advanced, interactive,
dynamic trajectory management system. To take advantage of
this sophisticated interactive calibration system, the
mechanical system has to be completely assembled and functionally tested prior to calibration in our best-in-class metrology labs. Nano-level system accuracy can only be
achieved under stringent environmental conditions, calibrating
with the best test equipment and utilizing the formidable
capability of Aerotech’s Dynamic Calibration Management
System.
An example can be seen in Figure 9 and 10. Figure 9 shows
the error motion of a rotary stage mounted to an XY linear
stage. Figure 10 shows the error motion after calibration. The
synchronous error reduced by over 2 μm.
We invite you to visit us and witness our test and calibration
procedures.
System Checkout and Certification
Each system component is extensively tested and exercised
prior to final system checkout. During final system checkout,
each system is optimized per the customer’s requirements. The
results of the testing and critical parameters are recorded,
preserved, and shipped with the system. This data, and how it
was obtained, is of utmost importance and serves as the
Certification of Compliance. Aerotech will not permit any
system to leave the premises unless it meets the stated
specifications. |
