Add convert-wheel-collision feature to automatically change wheel links to have cylinder collision shapes (#581)

Author: iory

setup.py

@@ -87,6 +87,7 @@ def remove_from_requirements(install_requires, remove_req):
 console_scripts.append("change-urdf-root=skrobot.apps.change_urdf_root:main")
 console_scripts.append("visualize-mesh=skrobot.apps.visualize_mesh:main")
 console_scripts.append("urdf-hash=skrobot.apps.urdf_hash:main")
+console_scripts.append("convert-wheel-collision=skrobot.apps.convert_wheel_collision:main")
 
 
 setup(

skrobot/apps/convert_wheel_collision.py

@@ -0,0 +1,140 @@
+#!/usr/bin/env python
+"""
+Convert continuous joint child link collision meshes to cylinders.
+
+This tool identifies continuous joints in a URDF file and converts
+their child links' collision meshes to cylinder primitives. This is
+particularly useful for wheel representations where cylinder collisions
+are more efficient for physics simulations.
+"""
+
+import argparse
+from pathlib import Path
+import sys
+
+from skrobot.urdf import convert_wheel_collisions_to_cylinders
+
+
+def main():
+    parser = argparse.ArgumentParser(
+        description='Convert continuous joint child link collision meshes to cylinders',
+        formatter_class=argparse.RawDescriptionHelpFormatter,
+        epilog="""
+Examples:
+  # Convert wheel collisions in a URDF file
+  convert-wheel-collision robot.urdf
+
+  # Specify output file
+  convert-wheel-collision robot.urdf -o robot_cylinder.urdf
+
+  # Modify the input file in place
+  convert-wheel-collision robot.urdf --inplace
+
+  # Process with verbose output
+  convert-wheel-collision robot.urdf -v
+        """
+    )
+
+    parser.add_argument(
+        'urdf_file',
+        type=str,
+        help='Path to the input URDF file'
+    )
+
+    parser.add_argument(
+        '-o', '--output',
+        type=str,
+        default=None,
+        help='Path to the output URDF file (default: input_cylinder_collision.urdf)'
+    )
+
+    parser.add_argument(
+        '--inplace',
+        action='store_true',
+        help='Modify the input URDF file in place'
+    )
+
+    parser.add_argument(
+        '-v', '--verbose',
+        action='store_true',
+        help='Enable verbose output'
+    )
+
+    parser.add_argument(
+        '--force',
+        action='store_true',
+        help='Overwrite output file if it exists'
+    )
+
+    args = parser.parse_args()
+
+    # Configure logging
+    import logging
+    if args.verbose:
+        logging.basicConfig(level=logging.INFO, format='%(message)s')
+    else:
+        logging.basicConfig(level=logging.WARNING, format='%(message)s')
+
+    # Check input file
+    input_path = Path(args.urdf_file)
+    if not input_path.exists():
+        print(f"Error: Input file '{args.urdf_file}' does not exist", file=sys.stderr)
+        return 1
+
+    # Check for conflicting options
+    if args.output and args.inplace:
+        print("Error: Cannot use both --output and --inplace options", file=sys.stderr)
+        return 1
+
+    # Determine output file
+    if args.inplace:
+        output_path = None  # Will modify in place
+    elif args.output:
+        output_path = Path(args.output)
+        # Check if output exists
+        if output_path.exists() and not args.force:
+            print(f"Error: Output file '{output_path}' already exists. Use --force to overwrite.", file=sys.stderr)
+            return 1
+    else:
+        output_path = input_path.parent / f"{input_path.stem}_cylinder_collision.urdf"
+        # Check if output exists
+        if output_path.exists() and not args.force:
+            print(f"Error: Output file '{output_path}' already exists. Use --force to overwrite.", file=sys.stderr)
+            return 1
+
+    try:
+        # Load and convert URDF
+        print(f"Loading URDF from: {input_path}")
+        print("Converting wheel collisions to cylinders...")
+
+        # Call the conversion function
+        modified_links = convert_wheel_collisions_to_cylinders(
+            str(input_path),
+            str(output_path) if output_path else None
+        )
+
+        if modified_links:
+            print(f"Modified {len(modified_links)} links:")
+            for link_name in modified_links:
+                print(f"  - {link_name}")
+        else:
+            print("No continuous joint child links found to convert")
+
+        if args.inplace:
+            print(f"Modified URDF saved in place: {input_path}")
+        elif output_path:
+            print(f"Modified URDF saved to: {output_path}")
+
+        print("Conversion completed successfully!")
+        return 0
+
+    except Exception as e:
+        print(f"Error: {e}", file=sys.stderr)
+        if args.verbose:
+            import traceback
+            traceback.print_exc()
+        return 1
+
+
+if __name__ == '__main__':
+    sys.exit(main())

skrobot/urdf/__init__.py

@@ -1,6 +1,8 @@
 from .aggregate import aggregate_urdf_mesh_files
 from .modularize_urdf import find_root_link
 from .modularize_urdf import transform_urdf_to_macro
+from .wheel_collision_converter import convert_wheel_collisions_to_cylinders
+from .wheel_collision_converter import get_mesh_dimensions
 from .xml_root_link_changer import change_urdf_root_link
 from .xml_root_link_changer import URDFXMLRootLinkChanger
 
@@ -11,4 +13,6 @@
     'find_root_link',
     'transform_urdf_to_macro',
     'aggregate_urdf_mesh_files',
+    'convert_wheel_collisions_to_cylinders',
+    'get_mesh_dimensions',
 ]