Ansys STK Shield Plus FAQ

Space and air missions operate within environmental conditions that vary significantly based on orbit, trajectory, mission duration, altitude, and operational objectives. Accurately defining these mission-specific parameters early in the design process is essential for evaluating environmental threats, guiding design tradeoffs, reducing program risk, and ensuring long-term system reliability.

Ansys STK Shield Plus bridges mission definition and survivability analysis by combining mission parameters with six integrated workflows for evaluating electromagnetic, radiation, charging, and lightning effects. This enables engineers to quantify mission-specific environmental threats, evaluate design margins, and assess survivability early in the development cycle before costly testing and redesign efforts occur.

Use Ansys STK Shield Plus to quickly screen mission-specific risks from:

• Electromagnetic radiation and electromagnetic interference coupling
• Lightning exposure along aircraft flight paths
• Cable shield performance under electromagnetic transients
• Total ionizing dose across shielding paths
• 3D radiation dose distribution around electronics
• Spacecraft surface charging and electrostatic discharge (ESD) risk  

Ansys STK Shield Plus Overview

What is Ansys STK Shield Plus?

Ansys STK Shield Plus is an add-on for Ansys STK that connects mission data with six automated survivability analysis workflows. It helps engineering teams evaluate environmental risks related to electromagnetic effects, lightning, radiation, and spacecraft charging using the actual orbit, trajectory, flight path, and operating conditions defined in STK.

Engineers can use STK Shield Plus to:

• Assess environmental threats earlier in the design cycle
• Compare design margins before hardware testing
• Identify areas that may need deeper EMC, radiation, or charging analysis
• Reduce the risk of late-stage redesigns

Who should use Ansys STK Shield Plus?        

Ansys STK Shield Plus is built for teams responsible for environmental survivability, mission assurance, and system reliability across space, aerospace, and defense programs.

Common users include:

• Aerospace and defense engineers
• Electromagnetic compatibility (EMC) engineers
• Radiation effects engineers
• Spacecraft and satellite systems engineers
• Mission analysts and mission assurance teams

How does Ansys STK Shield Plus extend Ansys STK with survivability analysis?

Ansys STK is used to model emissions, trajectories, orbits, and operational scenarios. Ansys STK Shield Plus extends those mission definitions with six automated survivability analysis workflows that evaluate how environmental threats may impact mission-critical systems.

With mission-specific data from STK, engineers can:

• Evaluate electromagnetic shielding effectiveness using full-wave simulation
• Assess lightning strike probability and risk
• Analyze cable shielding performance
• Generate ionizing radiation dose-depth curves
• Model 3D radiation dose distribution on sensitive electronics
• Evaluate spacecraft surface charging and ESD risk

By combining mission engineering with physics-based environmental analysis, STK Shield Plus estimates survivability risks and allows users to make informed decisions earlier in the development process. Learn more about the workflows in the Solving Electromagnetic Challenges webinar “Introduction to Ansys STK Shield Plus.” Watch here.

Electromagnetic Shielding Effectiveness Analysis

What is the electromagnetic shielding effectiveness workflow?

The electromagnetic shielding effectiveness workflow uses a full-wave Finite-Difference Time-Domain (FDTD) electromagnetic solver to evaluate how well an enclosure, subsystem, or platform protects sensitive electronics from electromagnetic radiation.

The workflow automates key setup and analysis steps, including:

• Material assignment
• Mesh generation
• Shielding effectiveness calculation
• Identification of potential weak points

This gives engineers a faster way to evaluate shielding performance before moving into more detailed design verification.

What types of systems can be analyzed for shielding effectiveness?

The shielding effectiveness workflow can be used to assess electromagnetic protection for mission-critical systems exposed to electromagnetic interference (EMI), external fields, or harsh electromagnetic environments.

Example applications include:

• Electronics enclosures
• Spacecraft subsystems
• Aircraft electronics
• Aerospace and defense platforms
• Mission-critical equipment requiring electromagnetic protection

How does shielding effectiveness analysis support mission reliability?

Shielding effectiveness analysis calculates electromagnetic vulnerabilities before they create system-level reliability issues. By using operating conditions from Ansys STK, teams can evaluate shielding performance in a realistic mission context and make better decisions about:

• Enclosure design
• Material selection
• EMI risk reduction
• Protection of sensitive electronics
• Design margin verification

Lightning Risk Analysis

How does Ansys STK Shield Plus calculate lightning strike probability?

Ansys STK Shield Plus uses mission parameters from Ansys STK, including the time spent at different altitudes, to estimate the probability of lightning strike induced failure. The analysis considers:

• Altitude exposure
• Flight path or trajectory
• Mission duration
• Lightning occurrence statistics
• Peak lightning current withstand level

The result quantifies whether the system’s lightning protection is adequate for the expected mission profile.

What mission parameters influence lightning risk analysis?

Lightning risk analysis depends on how and where the vehicle operates during the mission. Ansys STK Shield Plus uses trajectory, altitude profile, mission duration, and time spent within altitude bands to evaluate lightning exposure.

Key inputs include:

• Flight path or trajectory
• Altitude profile
• Time at altitude
• Mission duration
• Lightning occurrence data
• Designated peak lightning current withstand level

How does lightning risk analysis improve aircraft and mission reliability?

Lightning risk analysis identifies where lightning exposure is most likely to affect system performance or safety. Engineers can use the results to:

• Identify higher-risk mission phases
• Evaluate lightning protection design margins
• Reduce the chance of equipment damage
• Support certification and reliability assessments
• Make design updates earlier in the program

Cable Shielding Analysis

What is the cable shielding evaluation workflow in Ansys STK Shield Plus?

The cable shielding evaluation workflow analyzes how well a cable shield protects connected electronics from external electromagnetic interference.

Users define cable and source definitions, and the workflow calculates voltage induced at the cable termination where sensitive electronics are located. This determines whether the cable shield provides sufficient protection for the expected electromagnetic environment.   

What mission and cable parameters influence cable shielding analysis results?

Cable shielding results depend on both the electromagnetic environment and the physical cable configuration. Important inputs include:

• Cable length
• Shield type
• Electromagnetic source amplitude
• Source pulse width
• Mission environment conditions
• Cable termination location

These parameters affect how much electromagnetic energy couples onto the cable and how much voltage reaches connected electronics.

How can cable shielding evaluation help improve mission reliability and electromagnetic survivability?

Cable shielding evaluation identifies whether external EMI could couple into cable systems and affect electronics.

The workflow uses full-wave electromagnetic simulation with transmission line modeling to:

• Estimate electromagnetic coupling onto cables
• Calculate induced voltages
• Compare voltage levels against allowable thresholds
• Identify potential electromagnetic compatibility (EMC) vulnerabilities
• Support cable design and shielding decisions

Radiation Dose-Depth Curve Generation

What is radiation dose-depth curve generation in Ansys STK Shield Plus?

Radiation dose-depth curve generation calculates how ionizing dose changes with shielding thickness over the course of a mission.

Using the mission scenario from Ansys STK and particle physics capabilities from Ansys Charge Plus, the workflow generates dose-depth curves that show total ionizing dose (TID) at different material depths.

Engineers can use these curves to:

• Estimate shielding requirements
• Evaluate component survivability
• Compare material depth options
• Support radiation hardening decisions
• Assess cumulative radiation exposure

What mission parameters influence radiation dose-depth curve results?

Radiation dose-depth results depend on the radiation environment and the mission profile defined in Ansys STK.

Key factors include:

• Orbit
• Trajectory
• Mission duration
• Radiation environment models
• Shielding material depth
• Expected particle flux levels

These inputs affect the TID deposited in protected electronics.

How can radiation dose-depth curves improve radiation hardening and mission reliability?

Radiation dose-depth curves help engineers understand how shielding thickness affects TID at sensitive components. This supports radiation hardening by helping teams:

• Compare shielding options
• Determine whether components stay within tolerance limits
• Identify where additional shielding may be needed
• Reduce risk of radiation-induced degradation
• Improve confidence in long-duration system performance

3D Radiation Dose Modeling

What is 3D radiation dose modeling in Ansys STK Shield Plus?

3D radiation dose modeling predicts how ionizing radiation moves through complex spacecraft, aircraft, and electronic system geometries.

This workflow combines mission environments from Ansys STK with particle transport capabilities from Ansys Charge Plus to calculate three-dimensional dose distribution throughout the model.

This helps engineers:

• Visualize radiation exposure
• Locate dose hotspots
• Evaluate shielding effectiveness
• Estimate TID at critical electronics
• Understand component-level radiation risk

What factors influence 3D radiation dose modeling results?

3D radiation dose modeling is affected by both the mission environment and the physical design of the system.

Important factors include:

• Orbit and trajectory
• Mission duration
• Radiation environment models
• Material properties
• Material composition
• Shielding thickness
• Component location
• System geometry

Together, these inputs provide a more realistic view of radiation exposure than simplified shielding calculations alone.

How does 3D radiation dose modeling support radiation hardening and mission assurance?

3D radiation dose modeling shows how radiation dose is distributed throughout a vehicle, enclosure, or electronic system.

Engineers can use the results to:

• Identify localized dose hotspots
• Quantify TID at critical components
• Evaluate shielding effectiveness
• Optimize shielding placement
• Reduce radiation induced performance degradation
• Support mission assurance for aerospace, defense, and space systems

Spacecraft Surface ESD Risk Assessment

What is the spacecraft surface ESD risk assessment workflow in Ansys STK Shield Plus?

The spacecraft surface ESD risk assessment workflow evaluates how the space environment interacts with spacecraft surfaces to produce charging and ESD risks.

The workflow automatically:

• Calculates spacecraft surface potentials
• Identifies differential charging between materials and structures
• Maps charging distributions across the vehicle
• Highlights regions susceptible to ESD events
• Quantifies spacecraft charging risk using mission-specific environmental conditions

Using orbit, altitude, mission duration, plasma density, and particle energy data from Ansys STK, engineers can assess charging behavior early in the development process and identify potential ESD vulnerabilities before they affect mission performance.

What spacecraft charging effects can be identified with Ansys STK Shield Plus?

Ansys STK Shield Plus evaluates how the space environment interacts with spacecraft materials and surfaces to identify charging conditions that could threaten mission performance and reliability.

The spacecraft charging workflow can identify:

• Surface charging
• Differential charging
• ESD risk
• Localized charging hotspots
• High-voltage regions
• Charging distributions

These results enable engineers to identify charging-related risks, evaluate spacecraft susceptibility to ESD, and make informed decisions regarding materials, grounding approaches, and mitigation strategies early in the design process.

What mission and environmental parameters influence spacecraft surface ESD risk?

Spacecraft surface ESD risk depends on the mission orbit, altitude, duration, and surrounding plasma environment.

Relevant conditions include:

• Orbit type
• Altitude
• Mission duration
• Plasma density
• Particle energy levels
• Surface material behavior

These factors influence spacecraft charging, differential charging, and the likelihood of ESD events.

Mission Data

Can Ansys STK Shield Plus evaluate mission-specific risks instead of worst-case assumptions?

Yes. Ansys STK Shield Plus uses Ansys STK-defined trajectories, orbital environments, and operation scenarios to evaluate risks based on the expected mission profile.

Engineers can determine when conservative worst-case assumptions may overstate or misrepresent actual system risk. It also supports more targeted decisions for shielding, charging, mitigation, radiation hardening, and electromagnetic protection.

Ansys STK Shield Plus vs. Ansys EMC Plus and Ansys Charge Plus

What is the difference between Ansys STK Shield Plus vs. EMC Plus and Charge Plus?

Ansys STK Shield Plus is focused on mission-level survivability assessment. It uses parameters from Ansys STK to evaluate environmental threats across the mission profile. STK Shield Plus identifies areas of concern, while Ansys EMC Plus and Ansys Charge Plus support deeper verification, design trades, and mitigation studies.

Can results from Ansys STK Shield Plus be expanded into detailed EMC Plus or Charge Plus studies?

Yes. Ansys STK Shield Plus can help identify mission-level risks that may require more detailed analysis in Ansys EMC Plus or Ansys Charge Plus.

A typical workflow may include:

• Use STK Shield Plus for early environmental risk screening
• Identify potential EMC, radiation, or charging concerns
• Move selected cases in EMC Plus or Charge Plus for higher-fidelity analysis
• Evaluate design changes, mitigation options, or verification requirements

Ease of Use and Workflow Efficiency  

How quickly can studies be performed with Ansys STK Shield Plus?

Ansys STK Shield Plus accelerates survivability analysis through six automated workflows that streamline model setup, meshing, environmental configuration, solving, and post-processing.

The workflow reduced manual preparation by using mission data already defined in Ansys STK, helping engineers evaluate electromagnetic, radiation, charging, and lightning threats faster than traditional high-fidelity analysis workflows.

Do users need expertise in electromagnetic simulation?

No. Ansys STK Shield Plus is designed for mission engineers and system designers who need engineering-relevant survivability results without extensive expertise in electromagnetic simulation, radiation transport, or spacecraft charging physics.

Guided workflows help automate:

• Model setup
• Environmental definition
• Analysis configuration
• Solver preparation
• Result generation

This makes early-stage environmental risk assessment more accessible to teams working at the mission or system level.

How much model preparation is required?

Model preparation is minimized because Ansys STK Shield Plus uses mission parameters already defined in Ansys STK.

Reusable STK data may include:

• Satellite ephemeris
• Trajectories
• Orbit environments
• Flight paths
• Mission conditions

Users provide only the additional information needed for the selected workflow, reducing setup effort compared with traditional high-fidelity electromagnetic, radiation, or charging simulations.

Support, Training, and Getting Started

What support does EMA provide?

Electro Magnetic Applications, Inc. (EMA) supports teams using Ansys STK Shield Plus for mission survivability analysis, workflow setup, and result interpretation.

Support may include:

• Technical guidance for STK Shield Plus workflows
• Training for electromagnetic, radiation, charging, and lightning analyses
• Help interpreting simulation results
• Assistance identifying mission-specific risks
• Support transitioning to detailed Ansys EMC Plus or Ansys Charge Plus studies

Who should reach out to EMA?

Organizations should contact EMA if they need help evaluating environmental threats that can affect mission-critical electronics, spacecraft, aircraft, or defense systems.

This includes:

• Mission engineers evaluating survivability risks
• Spacecraft and avionics engineers assessing radiation, charging, or EMI threats
• EMC and ESD specialists investigating shielding or system reliability
• Teams integrating mission engineering with physics-based environmental analysis

How can I get started?

To get started with Ansys STK Shield Plus, teams can contact EMA to discuss their mission environment, technical goals, and analysis needs.

You can:

• Request a technical consultation
• Discuss your mission or technical challenge
• Explore simulation and testing options
• Identify which STK Shield Plus workflow fits your case.

Contact EMA to speak with an expert and see how Ansys STK Shield Plus can support your program.