OVERVIEW

IPS is a general purpose implementation of nonlinear indicial theory, applicable to systems with multiple dependent and independent variables. The IPS formulation is based on characterizing nonlinear systems using a kernel of nonlinear indicial responses (IR) and critical-state responses (CSR). IR/CSR parameterizations can be mixed (i.e., discrete or continuous) and arbitrary-dimensional.
 
The kernel responses of a nonlinear system can be determined analytically, numerically, or experimentally, whichever is available or appropriate. The kernel identification problem amounts to an initial investment, either in terms of experimental data or in terms of simulation results, from which the behavior of the system can then be generalized/predicted at a small computational cost.
 
Once system modeling (choice of inputs and outputs) and problem parameterization are performed by the user, IPS can be used in either prediction mode or extraction mode. The prediction module calculates the system response by integrating that system's indicial (step) and critical-state (bifurcation) responses. The extraction module performs the inverse problem of determining the system's kernel of nonlinear indicial and critical-state responses, based on observed data.
 
IPS has been applied to problems in high angle-of-attack aerodynamics, electronics, and aeroservoelasticity. The software user manual contains a comprehensive description of both the program's options as well as program interfaces with external modules. Use of the Indicial Prediction System is also illustrated through detailed sample cases.
 
The IPS environment offers the following advantages:

	Well-suited for high-fidelity modeling of nonlinear plant characteristics for advanced control.
	Systems approach to modeling unsteady nonlinear processes.
	Solves real-world nonlinear problems; creates mathematical models for complex processes, bypassing lengthy stages of program/code development and debugging.
	Reduces model development time.
	Well-suited for quick development of nonlinear systems as proof-of-concept.
	Easy model adaptability.
	Flexibility to address many applications.

• Process modeling
• Behavior prediction
• Generalization / Extrapolation
• Filtering
• Data segmentation
• System identification
• Time-series modeling/forecasting

• Fast execution
• Easily used
• Interactive control 
• On-line help
• Robust system identification from observed data
• Automatic domain harmonization
• Fine-tuning by training
• Powerful data analysis
• Robust conflict handling
• Extensive software user manual / tutorial
• Technical support

 

• Flight simulation 
• AeroServoElasticity 
• Control system design/analysis
• Data analysis/modeling
• Electronics 
• Vibration analysis/control
• Acoustics 
• Earthquake Engineering 
• Training/Instructional tools
• General R&D
• System identification 

• IPS is available in CDROM format
• Requires a software license and agreement from NEAR
• IPS has been sucessfully tested on the following operating systems: Linux i386, Solaris 2.5, and SGI IRIX 6.4.
• Executable sizes: less than 2 Mbytes
• Disk space needed for installation: less than 10 Mbytes
• Prediction module performance: Single node problem: 22 ms per output on a 266 MHz PC.  Eight node problem: 73 ms per output on a 266 MHz PC.

NEAR also openly seeks third party and joint ventures to distribute and market IPS.  For further information, contact info@nearinc.com.

NEAR offers software, consulting, and R&D capabilities and openly seeks third party and joint ventures to further develop the Indicial Prediction System.
 
Opportunities for future development include:

• Real-time implementation
• Multitasking
• PC/Windows portability
• MATLAB compatibility for easy data manipulation (pre- and post-processing) and plotting
• Volterra-Wiener theory
• Web-based computing