Hi there,
This is Bogdan from Romania.
I'm a mechanical engineer - specialized in the industrial robotic field, 3D designer, industrial designer and, 3D modeler.
For some of my projects, I'm also doing the physical prototype too.
I'm doing product design, industrial design, reverse engineering, ideation, etc.
I have over 15 years of experience working on various systems/devices across multiple industries, from concept to launch.
1 - will need to know what you have to add more to the leash besides already on the market - there are hundreds of models...
2 - except the flat spring, you also need a slip clutch (to allow free extension and retracting of the leash), ergonomic handle, some addons/enhancements, etc
3 - depending on the leash type to be used (flat or round) it is necessary to have some guidance and a piece to prevent tangling on the flat leash
For any more questions, we could chat here, including the whole details of the project, final price, time frame, deliverables, etc, etc...
Regards
Bogdan