Main Window - Perspective


ORBIS is a computer program to solve the nonlinear elastic behavior of rolling-element ball bearings. The model considers each ball-to-race contact for all bearing rows defined in the system (up to 5 rows allowed); resulting in complete knowledge of element load distributions and their raceway attitudes. Core analysis methods are based on industry standard A.B. Jones theories. ORBIS also implements a ring compliance model based on classical thick ring theories to determine the final mounted and preloaded state of the bearing system. This model is also used for assessing thermal strains.

The program offers a graphical interface designed by a bearing analyst to be useful and intuitive. Our mission is to make ORBIS the 'industry standard' for rolling-element bearing analysis software.

Screenshots (Hover over to expand)

Feature Overview

ORBIS is a full-featured bearing analysis tool. Table 1. lists general features and Table 2. lists available analysis outputs. See the "Key Tools & Features" section below for further details about the many advanced utilities.

Table 1. ORBIS Features
  • Modern graphical interface
  • Direct temperature loading
  • Fitup/interference considerations
  • Ring clamping effects
  • Multiple point 5 DOF loading
  • Analyze 5 bearing rows on a common shaft
  • Truncation analysis
  • Fatigue life w/ adjustment factors
  • Parameter sensitivity plotting
  • Tolerance analysis
  • Flexible shaft modeling
  • Ball speed variation
  • Unlimited No. balls per row
  • Dahl stiffness & hysteresis plotting
  • Lubricant film thickness
  • User defined databases
  • Load case batch processing
  • 64-Bit compatible
  • Data plotting
  • Data export to Excel®

Table 2. ORBIS Outputs
Row & System Level Rolling-Element Level
  • All input parameters
  • Ball crossing angles
  • Internal clearance changes
  • Ring distortion properties
  • Mounted preload forces and deflections
  • Row reaction forces on shaft
  • Inner ring displacements
  • Axial stiffness w/ ring compliance
  • System Jacobian (diagonals)
  • Full row stiffness matrices
  • L10 & adjusted fatigue life
  • Lubricant & reliability life factor calculations
  • Coulomb & viscous bearing torques
  • Maximum ball excursions
  • Normal ball loads
  • Contact angles
  • Mean Hertzian stresses
  • % truncated length
  • Truncated center & edge stresses
  • Ellipse dimensions (major & minor)
  • Max sub-surface shear stress
  • Depth of max shear stress
  • Upper & lower contact extremities
  • Contact normal approach
  • Contact normal stiffness
  • Element spinning velocities
  • Element rolling velocities
  • Spinning torque
  • Rolling torque
  • Pitch orbit velocity
  • Minimum film thickness
  • Minimum film Lambda values
  • Centrifugal forces
  • Gyroscopic moments

Why Choose ORBIS?


In addition to analyzing multiple bearings on a common shaft, ORBIS provides many tools and features to aid in the design and optimization of the user defined system. For instance, the sensitivity tool allows almost any input parameter to be independently varied and plotted against one or more output parameters. Other tools include tolerance analysis, flexible shaft modeler, batch processing and Dahl torque hysteresis. See the Key Tools & Features section for further details.


ORBIS is built on core methods published by A. B. Jones and has become the trusted bearing analysis solution for industries extending from bearing manufacturers to aerospace and defense companies. In addition to verification from our clients, ORBIS accuracy has been validated by comparing numerous test cases with the Jones program.

Ease of Use

By adhering to clear and instinctive data input, and organizing information in an intuitive manner, we believe you will find the ORBIS interface easy to use. Customizable bearing, material and lubricant databases save time by 'remembering' numerous parameters that are often reused.

Long Term Dependability

Since the first version release in 2009, we have continued developing ORBIS. We believe clients should not have to purchase new versions every time a feature is added. To address this, software licenses are leased and all users receive new version releases. Also, the Java® development platform was specifically chosen due to its robust compatibility with various computer operating systems and machine architectures. Our mission is to make ORBIS the industry standard for rolling-element bearing analysis.

User Base

The ORBIS user base consist of bearing manufacturers, missile and defense contractors, and the aerospace industry. Please contact us for more user information.

Key Tools & Features

Sensitivity Studies Image

Sensitivity Studies

This utility provides a quick way to study the sensitivity of the bearing system. The tool generates plots of selected system parameters against independent input variables. These plots enhance understanding of the effect each input parameter has on the bearing system.

Table 3., lists available independent and dependent parameters that can be studied with the Sensitivity tool. Multiple dependent parameters can be selected and separate plots will be generated automatically. Raw plot data can be exported to a text file for further analysis.

Sensitivity Studies Image
Table 3. Sensitivity Input Parameters
Independent Parameters Dependent Parameters
  • All load DOF's: Fx, Fy, Fz, Fyy, Fzz
  • Load location along shaft
  • Shaft temperature
  • Housing temperature
  • Bulk Temperature
  • Rotational Velocity
  • Free Contact Angle
  • I.R. & O.R. Curvatures
  • Radial Play
  • Rolling & Viscous Friction Coefficients
  • Row Locations
  • I.D. & O.D. fitups
  • Preload
  • Preload Spring Rate
  • Preload Spring Snubber Gap
  • I.R. & O.R. clamp loads
  • Radial & Axial Play
  • I.D. & O.D. Expansions
  • I.D. & O.D. Fitups
  • Preloads
  • Row Deflections
  • Row Reaction Forces
  • Fatigue Life
  • Bearing Resistive Torque
  • Maximum Ball Excursions
  • Rolling Element Normal Loads
  • Contact Angles
  • Contact Stress
  • Sub-Surface Shear Stress
  • Contact Ellipse Heights
  • Film Heights
  • Film Parameter (lambda)
Shaft Flexibility Image

Flexible Shaft Analyzer

This utility is used to account for elastic compliance of the bearing shaft, thereby allowing independent bearing rotation attitudes based on the structural stiffness of the shaft. The elasticity model uses Timoshenko beam element formulations that account for both bending and shear deflections in the shaft. The user can define up to 25 unique circular beam elements on a given shaft; each of which may contain unique cross section dimensions and/or materials. Deformed shaft shape can also be plotted.

Tolerance Dialog

Tolerance Analysis

This utility iteratively solves all permutations of key tolerances. Minimum and maximum values for preload, ID/OD fitups, contact angle or radial play, and curvatures can be assessed. Additionally, the sign convention on each load component can be specified to run through all plus-minus combinations. The tool seeks tolerance combinations to cause maximum contact stress. Additionally, if truncated contacts are found, the tool will find the worst case tolerance conditions to cause the largest percent truncation.

Dahl Torque Image

Dahl Torque Hysteresis

The Dahl Torque Hysteresis utility is used to analyze the torsional stiffness (torque versus angle) of the bearing system during startup or direction reversal. This phenomenon occurs through small finite angles of rotation, often most apparent when direction of rotation is reversed, at speeds sufficiently slow such that viscous drag is negligible. The utility provides quick inspection of the reversing torque slope and steady state torque. Additionally, the utility can quickly generate small angle hysteresis loops for both graphical plot inspection and data export.

Plot Windows

Data Plotting and Exporting

Most tools support data plotting and data exporting. Plot windows are interactive and provide click-n-drag mouse zooming, complete plot reformatting, and the ability to save final plots to image files. Data exporting provides delimited text file output formats that can easily be imported into other software (such as Microsoft Excel®).

Batch Processing

Load Case Batch Processing

The batch processing utility allows import of a .csv file with multiple load cases defined and will process all cases against the configured bearing system. Main result parameters, such as maximum stress, percent truncation, and resistive torque are tabulated against each load cases for quick review. Any case from the result table can sent to a full result window for detailed inspection. The result table can be exported to a text file for further post processing. Additionally, a full detailed result file can be automatically generated and saved for all load cases.

Plot Windows

Margin of Safety

The Load Margin of Safety tool calculates a true load margin on the defined system of bearings. The reported margin is the percent load increase, expressed as a decimal, that could be applied to the defined load to reach a specified limit criteria. Option for limiting criteria are maximum mean stress and/or truncation; where the tool reports the margin to the first limit criteria found. Furthermore, truncation limits can be adjusted to a maximum allowable percent truncation (i.e. allow a maximum of 10% truncation).

Hertzian Contact

Hertzian Contact Analysis

The Hertzian Contact tool is a general engineering tool to solve classical Hertzian point and line contact problems. The tool solves arbitrary two body contact problems and provides the resulting contact stress, elliptical contact area, linearized contact stiffness and sub-surface shear stresses. Since the tool uses the main material database, only body radii and the normal load are specified to run the analysis.

System Requirements

ORBIS requires the following minimum system requirements: