Knowledge Base

System Configurations & Licensing

CatWalk 11.0 is available with either a hardware key (USB dongle) or a software license. Software licenses offer two modes:

License Types

• Fixed License — Tied to a single computer. Deactivation required before transferring to another machine. May be activated online or offline (via QR code).
• Floating License — Usable on multiple computers sequentially (not simultaneously). Requires internet connection on the acquisition computer. Multiple floating licenses allow simultaneous use.
• Perpetual License — One-time purchase; software may be used indefinitely.
• Time-Limited License — Valid for a defined period (typically 6 or 12 months). Online activation only.

Analysis Mode

CatWalk can be installed on additional computers without a license. In unlicensed analysis mode, users can open experiments, classify runs, create data and parameter profiles, run all analysis functions, and export all data and statistics. New data acquisition is not possible without a valid license.

Data Management

Experimental Setup

• Animal Type — Select Rat or Mouse. Determines the Automatic Footprint Classification algorithm and the Sciatic, Tibial, and Peroneal Functional Index formulas.
• Time Points — Define and label the time points at which data are acquired, with optional colour coding for group statistics.
• Treatment Groups — Define groups with type (Undefined, Experimental, Control, Sham), name, description, and display colour.
• Run Criteria — Set minimum and maximum run duration, minimum number of compliant runs to acquire, and an optional maximum allowed speed variation threshold. Runs not meeting criteria are marked non-compliant; acquisition continues until the required number of compliant runs is reached.
• Trial List — Pre-plan trials with animal ID, time point, group assignment, and optional description. Trial names are unique identifiers. The list shows acquisition status, total runs, compliant runs, and classification status for each trial.

File Management

• Experiment Setup Profiles — Save and reuse a set of experiment settings (time points, treatment groups, trial structure) across new experiments.
• Preferences — Distance unit (millimetres, centimetres, or inches), decimal precision for numbers, times and percentages; folder locations; auto-save interval; paw display colours.
• Experiment Files — Stored as *.cwe files within a named experiment folder.
• Backup and Restore — Experiments can be backed up to *.cwz archives and restored from them. Auto-save at configurable intervals (default: every 5 minutes).
• Backward Compatibility — CatWalk 11 opens and converts experiments from versions 8.x, 9.x, 10.x. Experiments from versions prior to 11 are read-only (analysis only; no new acquisition). Experiments from versions 7.x or earlier cannot be opened.

Walkway Setup

Setup Workflow

Setting up the walkway involves three sequential steps, each supported by a dedicated tool:

1. Focus Assist — Interactive tool to focus the camera lens. A sharpness indicator (percentage of maximum reachable sharpness) guides the user. A bottom-image view highlights sharp areas for real-time feedback.
2. Automatic Walkway Calibration — After focusing, a dedicated calibration card placed in the walkway is detected automatically. Calibration converts pixel dimensions to real-world units (mm/pixel). Manual calibration is possible but not recommended.
3. Automatic Walkway Definition — The software automatically detects the corridor walls and defines a walkway rectangle covering 70% of the walkway length. The walkway can be resized and repositioned manually. A Validate Walkway function checks corridor-wall alignment at the start of each acquisition session.

Once set up, the walkway configuration is retained across sessions. Re-setup is only required if hardware is changed (e.g., camera position, corridor width).

Detection Settings

• Auto Detection — With an animal on the walkway, CatWalk automatically adjusts Camera Gain and Green Intensity Threshold to achieve optimal paw-print intensity (target: Maximum Green Intensity 197–203). Default Detection Settings profiles for Rats and Mice are provided.
• Manual Detection — Camera Gain and Green Intensity Threshold can be fine-tuned manually. The intensity of the Green Walkway Light and Red Ceiling Light can also be adjusted.
• Camera Gain — Controls Maximum Green Intensity of detected prints. Optimal range: 5–12 dB.
• Green Intensity Threshold — Sets the minimum pixel intensity for paw detection. Removes background noise. Can also be adjusted per run in the Classification screen before classification.

Source: CatWalk XT 11.0 Technical Specifications, Noldus Information Technology