2. 228 April 2014
ABOUT SYNAPSE
Synapse helps leading companies deliver breakthrough experiences through
technology. Fueled by solving impossible engineering challenges, we develop
products that transform brands and accelerate advances in technology
www.synapse.com
3. 328 April 2014
WHAT SYNAPSE DEVELOPS
■ Connected Devices
■ Guest Experiences
■ Wearable Devices
■ Enterprise Software Solutions
■ Consumer Electronics
■ Health and Fitness
■ Transferable Tech
NIKE+ FUELBAND 2012-2013 VIABLEWARE RAIL 2012
PROPELLER SENSOR 2011NIKE+ SPORTWATCH GPS
POWERED BY TOMTOM 2011
PANASONIC AVIONICS SYSTEM
(PROTOTYPE) 2009
5. 528 April 2014
HISTORY OF ANSYS HFSS
Left: Press Release, October, 1990 Ansoft
Corporation ships the High Frequency Structure
Simulator (HFSS) for exclusive sale by the Hewlett
Packard Company.
16 hours in 1990
3 seconds in 2007!
Below: Ansys has come a long way since then.
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WHY WEARABLES?
■ High value placement
■ More pervasive and less invasive
■ Speed of data assimilation
To generate the right data with sensors in the right place
and a way to view or share that data instantly.
Left: Google Glass kicked off the wearable tech trend. Middle: Sproutling, a San Francisco based startup, is
developing a new baby monitor. Right: Armour39® is a heart rate monitor that displays performance stats
via mobile app and/or a display watch.
10. 1028 April 2014
APPLICATIONS OF THE IOT
■ Mapping disease
● GPS, biometric vitals
■ Digital identification
● Unique biometric characteristics
■ Customization and control
● Proximity (GPS, BLE, NFC), interface
■ Human insight
● Collection and communication
of data
SENSORS + MACHINE-TO-MACHINE COMMUNICATION (M2M)
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RF CHALLENGES WITH WEARABLES
■ Material selection based on
• Comfort
• Fashion
• Durability
• Allergens
■ Resistance to personal products
■ Waterproofing
Above: Instabeat Heart Rate Monitor
Above: News Headline, Allergic
Reactions Cause Fitbit To Recall
Wrist-worn Force Fitness Tracker
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3 RF HEAVY HITTERS
Absorption Materials Antenna Size
Above: Renderings
of a wrist band
13. 1328 April 2014 Synapse Confidential
RF NEAR THE BODY
■ Absorption because you’re a bag
of water
■ Comfort & size = movement
● S11 match shifts due to the influent of
the body
● Efficiency changes
■ Body movement
● Rotations causes gain variation
● Generally hurts the link budget
HUMAN BODY IMPLICATIONS
Bottom Right: S11
variation due to
movement
Top Right: Model of
an oscillating wrist
14. 1428 April 2014
THE COMPLEXITY OF WEARABLES
■ Human body modeling
■ Size variations
■ Simulating movement
Low Resolution Medium Resolution High Resolution
(4 mm version) (2 mm version) (accurate version)
19. 1928 April 2014 Synapse Confidential
WE THINK ABOUT USE CASE FIRST
Understanding your user
● How often does sampling need to
occur? (heart monitor & footfalls)
● User Interaction Rate
● Comfort
Drives the engineering
● Power
● Connection Interval
● Experience
● Connection Technology
● Link Budget
UNDERSTAND YOUR USER
Above: GPS Running watch example.
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SIMULATION TIMES
■ Rapid development requires rapid sim times
■ Keep sims times less than an hour until CAD is final
■ Multi core license is well worth the money
■ We run large sims on remote machines
■ Small jobs are run on laptops
■ Cloud computing is also an option
■ Parametric sweeps and optimizations are typically run overnight
■ Analytical Derivative Function using Optimetrics to speed
understanding of design space
24. 2428 April 2014 Synapse Confidential
RAPID MODEL
WORKFLOW
Above and Below: ME
refinement
25. 2528 April 2014 Synapse Confidential
COMPLEXITY OF ORGANIC 3D MODELS
■ Developing 3D elements within curve
surfaces is extremely important
■ Simplify CAD and HFSS model to solve
quickly and allow rapid iterations
■ Imported CAD to modeled surfaces
increases solve times
■ There are several methods to simplify
CAD
● Sweep simple geometric shapes based on
polylines
● Use HFSS meshing views to and controls to
reduce tetrahedron counts
● Use imported CAD and manipulate with CAD
simplification tool like SpaceClaim
Simplifying CAD
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SENSITIVITY ANALYSIS
■ Sensitivity is some that needs to be verified throughout the project
■ Many real world factors conspire to reduce bandwidth
■ Many unintended modifications can cause shifts in the antenna
resonance point
■ The desire for rapid development can lead to missing elements that
effect the physical design
■ Informed knowledge of where short cuts can be taken is crucial
■ As in most RF generally, BW is protection against sensitivity
■ Wearable antenna design is a tradeoff between footprint and BW
● Small antennas tend to be narrowband
● We want to widen the BW while minimizing footprint
30. 3028 April 2014 Synapse Confidential
MP DESIGN / SENSITIVITY
■ Working element is ported into
Solidworks for ME interference
checks
■ ME architecture generally requires
manufacturability changes
affecting RF antenna
■ ME CAD architecture is imported
back into HFSS and crossed
checked with RF design concept
WORKFLOW
ME import
32. 3228 April 2014 Synapse Confidential
ALPHA LOCK
WORKFLOW
■ RF antenna sensitivity is finalized
■ Detailed RF verification and
reaction to ME changes
■ Typically begin generating
prototypes
33. 3328 April 2014 Synapse Confidential
CHARACTERIZATION
■ S11 testing in the lab and in a
Satimo chamber validates design
for mass production
■ Environmental and sensitivity
testing validates design
WORKFLOW
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SCRIPTING HFSS FOR SPEED
■ Trigonometric functions are more easily defined in a script
■ Scripting allows each 3D point to be broken into its constituent
points
■ Trace widths, separation, height etc can all be parameterized easily
■ Parameterized models allow early rapid design space exploration
■ Parameterized models also enables later automated optimization
■ 3-Dimensional antenna concepts are difficult to parameterize
■ Python scripts offer a simple way to scale elements
● Number of elements in an antenna
● Fractal elements
● Number of turns in a coil
36. 3628 April 2014 Synapse Confidential
WHY BOTHER USING SCRIPTS
+ Organization of complex values
+ Reuse
+ Minor changes provide major
impact
- Script debug is difficult
PLUSES AND MINUSES
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THE TAKEAWAYS
■ RF challenges and design considerations for the human body
■ Start early and sync often with your ME design team
● Rapid development requires parallel workstreams
● We need to be flexible in design to allow for ID material choices
■ How we leverage HFSS
● Scripting enables parameterization
● Parameterization enables rapid development
■ View this deck again at:
synapse.com/blog/post/ansys-hfss
■ Visit the ANSYS booth (#1413) at DAC!
● Mike presents again June 2nd at 2PM
Notes de l'éditeur
Currently ~150 RF/ME/EE/FW/SW engineering consultantsWe develop consumer and other products most have RFCustom antenna design is a key differentiatorUse cases drive the requirement which outline solutionsIntegration of ME/EE/RF/FW critical to successUnderstanding electromagnetics in challenging environmentsCreativity drives innovation
Who are Synapse customers: Startups to Fortune 100 companiesInnovators with an idea
WearablesIntegrate antennasRF on FPC, highly integratedVery small footprintSystems integrated front end to the backendCustom antennaPhased arraysSmall antenna
Bring the people aspect to - why we love RF and ...22 years experience in numerical simulationExperience on HFSS in the team goes back 15 yearsHFSS allows Speeds time to market - Determination of RF performance prior to final designEarlier design iteration speeds product time to market no need to wait for ME protosThe integrated approach allows ME/EE and RF to proceed in parallel ME and RF to work virtually seamlessly togetherThis design process provides method to validate many possible solutions Flexibility to react to late breaking change in ME
Design for the human bodyChallenges of this type of designHow to rapidly develop integrated antennasAbout parameterization and how we can enable rapid design on extremely complex surfaces How scripting enables the parameterizationBut first lets talk about why wearbles, A future vision
Daughter anecdote?
RF question the question is how do we connect...Cheap wireless interconnect to the internetLow power devices - wireless chips and sensorsSilicon has gotten us to the point that enables this
Map disease: we worked with a company called propeller health to create a BLE module for inhalers that triggered a data collection process on the phone, so they could see and understand patterns of asthma attacks, and share that insight with doctors. Generating and understanding data like this from sensors in the right place could allow us to monitor and predict heart attacks, strokes, or diabetes.We’re finding ways of identifying ourselves. The username and password paradigm is ending, and we’re using sensors to measure us, so we become the key to unlocking the world around us.And that world is gaining a digital layer that we can interact with, control, and customize.Aiding human control (Proximity, GPS, M2M)By generating all this data and understanding the context, we can yield incredible insight. The I-O-T will enable the next major leap in quality of life.
Comfort Industrial Design - FashionDrives special materials based usability not RFResistance to personal productsSensitivity to allergensDurability of materialsWaterproofing
3 design issues with RF near the bodyAbsorptionMaterialsAntenna Size
Human body modeling - Several approaches Ansys complete human body Simple solids and human body material assignment Know when to ignore itSize variations - size equates to more absorptionSimulating movement - Using a coordinate system, a variable and the parametric sweep function can help you understand your design’s sensitivity to movement relative to the body
We’ve moved into an internet-first modality (google it first..)All our experiences are designed with connectednessWearables help encode the physical into digitalRF allows us to communicate with the digital layerBecomes like a “6th sense”
Typically we use 2.4 GhzUbiquitous connection to phones and cheapRobust yet low powerIMS band flexibilityReduced efficiency requirementsGPS at 1.5GhzDemanding antenna efficiencyOmni directionality or gain shaping2G GSM at 800-900 and 1800- 1900MhzM2M connection of choice right now.
Process starts in HFSS and Solidworks simultaneouslyRapid model iteration supports tradeoffs of ID, ME, EE and RF requirementsDevelopment of a workable element in a simple RF architecture while ME develops a similar ME architecture in SolidworksParameterized antenna element enables exploration of design spaceAddition of simplified materials to represent critical components (closer than 1/10 wavelength) and all metallic items
This needs to be redone with non IP versionNeeds soundNeed lower resolution
Rapid development requires rapid sim timesWe try to keep sims around an hour max at least until we are close to final CADMulti core license is well worth the moneyWe run sims from batch script on a fast dedicated remote machineRemote cloud computers are an optionParametric sweeps and optimizations are run overnight typicallyAnalytical Derivative Function using Optimetrics to speed understanding of design spaceSmall jobs are run on laptops and larger jobs on large remote machinesTest results of sim times.
At this phase of the design the ME starts to firm up and CAD imports are getting largeWe work hard to reduce complexity and keep sim time to <1hrMaterial selections are being determined and revised (keep in mind ME may require material changes later)DXF out to layout and dxf in to verify layoutStep file out to ME to build some parts, sheet metal antenna, LDS Sat file back into HFSS to verify design internt and check materials shapes, loading, and other impactsIn the bottom right is a higly integrated antenna, we try to remain as far above this level and we can for as long as we can
Workable element ported into Solidworks, ME interference checks occurME architecture generally requires manufacturability changes affecting RF antennaME CAD architecture is imported into HFSS and crossed checked with RF design concept
Put the CAD import on it own coordinate system because many times coordinate systems change as we go along and this allows of to move or rotate the CAD for what ever we needIf we don’t do this, it is a difficult process to change each import later.You’ll see me using a lot of coordinate systems, again it’s about rapid reactionParameterization
Physically build prototypesRelease pieces to ME vendorsRF antenna sensitivity is analyzedDetailed RF verification, reaction to ME changes, prototypes generation generally occur now
Synapse often creates Python , there are others scripts to deal with the complexity of the trigonometric functions required to build parameterized models
