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We are developing a premium adjustable dog leash designed to integrate with an existing premium dog collar. We need an experienced mechanical/product design engineer to evaluate the concept, simplify it where necessary, and create a safe, reliable, prototype-ready and manufacturing-oriented mechanical design. This is a functional engineering project, not only a 3D modelling or rendering project. CORE REQUIREMENTS 1. Adjustable premium leash - Three positively locked lengths: 1.2 m, 1.5 m and 1.8 m. - Length adjustment only when the leash is not under load. - Positive mechanical locking, not friction-only locking. - Initial prototype: approximately 25 mm wide, flat, multi-layer premium high-tenacity polyester webbing with a dense, smooth, soft-touch matte finish. - The leash webbing must independently carry the full pulling load. 2. Emergency-release handle - Ergonomic finger-operated release lever inspired by a trigger, but not visually resembling a weapon. - Protected lever with guard. - Separate mechanical thumb safety slider. - Two deliberate actions: unlock safety slider, then press release lever. - Clear mechanical travel and resistance. - Automatic return to the safe/locked condition. - One-handed operation for right- and left-handed users, including wet hands or gloves. - Must not release due to impact, accidental grip, friction, partial lever movement or safety-slider failure. - Padded handle loop with a small rigid external mechanism housing. - The rigid housing must not carry the dog’s pulling load. 3. Mechanical control cable - Stainless-steel control cable inside a protected low-friction sheath. - Excess cable/sheath created by the three leash lengths must be safely stored inside a protected handle cartridge. - No loose external cable loops. - Adequate bending radius. - Consistent lever force and travel in all three length positions. - Cable and sheath should be serviceable. - Cable failure, breakage or detachment must leave the leash locked. - The leash must remain structurally safe even if the cable is removed. 4. Leash-to-collar connector - Cylindrical leash-side connector. - Gentle funnel-shaped entrance for one-handed insertion. - Central concealed magnet for alignment only. - Spring-loaded stainless-steel locking pin passing fully through the cylindrical connector. - Clear mechanical click when fully locked. - Direct mechanical red/green lock indicator. - Hidden keyed/flat guiding feature to align the locking hole with the pin. - The magnet must not carry pulling load. - No 360-degree swivel in the first prototype because it may twist or complicate the mechanical release cable. 5. Normal and emergency release - Normal daily disconnection through a small protected button on the collar connector. - Handle release reserved for emergencies. - Emergency release path: thumb safety slider -> protected release lever -> control cable -> internal lever -> pin retraction. - Internal lever should reduce the force required to withdraw the pin. - Fail-locked behavior required: - Broken or loose cable must not release the leash. - Failure of the length-adjustment mechanism must not release the leash. - Release input removed -> pin returns to locked position. - The engineer must evaluate release under load. 6. Materials Preferred architecture: - Lightweight premium aluminum external housing. - Stainless-steel internal load-bearing parts. - Stainless-steel locking pin and cylindrical connector. - Replaceable low-friction engineering-polymer bushing. - Premium high-tenacity polyester webbing. - Aluminum exterior must not independently carry the full load. - Prevent galvanic corrosion between aluminum and stainless steel. - Final grades and dimensions must be selected through engineering analysis and prototype testing. 7. Serviceability Where practical, the following should be replaceable: - Internal bushing. - Pin/spring cartridge. - Cylindrical connector head. - Control cable and sheath. 8. Initial prototype - One medium/heavy-duty prototype first. - Small, medium and large versions only after the architecture is proven. 9. Existing collar - Existing collar design is available in editable CAD, STEP and STL. - The leash connector will mount opposite the main collar buckle, on the top/dorsal side of the dog’s neck. - Confidential collar files will be shared only after shortlisting, NDA acceptance and project award. - The connector must anchor to the collar’s internal load-bearing structure, not only silicone, padding or decorative surfaces. 10. Required testing approach Prepare a practical bench-test plan covering: - Static load and stress testing. - Sudden pull/shock-load testing. - Emergency release under load. - Testing in all three length positions. - Accidental-release prevention. - Repeated connection and release cycles. - Wear of pin, bushing, cable, spring, trigger and length-adjustment mechanism. - Basic exposure to water, sand, hair and light mud. - Cable-failure testing. - Verification that the red/green indicator cannot show locked unless the pin is fully engaged. Initial tests must be performed on a bench fixture, not on a live dog. MILESTONES Milestone 1 - Feasibility and mechanical architecture - Written feasibility assessment. - Proposed complete mechanical architecture. - Load-path explanation. - Cable routing concept. - Three-position length-adjustment concept. - Excess cable/sheath management concept. - Fail-locked behavior explanation. - Main failure, wear and manufacturing risks. - Standard versus custom component list. - Concept sketches or simplified CAD. Detailed final CAD must not begin before approval. Milestone 2 - Preliminary CAD - Preliminary complete assembly. - Internal section views. - Handle, safety slider and release lever. - Length-adjustment mechanism. - Cable-storage cartridge. - Cylindrical connector and collar interface. - Initial material/component selection. Milestone 3 - Prototype-ready CAD - Complete editable native CAD assembly and part files. - STEP files. - Required STL files. - Exploded views. - Assembly method. - Critical tolerances and clearances. - Replaceable wear-part design. Milestone 4 - Engineering documentation - Manufacturing drawings in PDF. - Complete BOM. - Pin, spring, magnet, cable, sheath, bushing, fastener and seal specifications. - Assembly instructions. - Cable-tension adjustment procedure. - Bench-test plan. Milestone 5 - Post-prototype revision - Review prototype/test results. - Correct issues found during assembly/testing. - Deliver updated final editable CAD, STEP files, drawings and documentation. PAYMENT AND ACCEPTANCE - Fixed-price project divided into separately approved milestones. - Milestone funds will be released only after the written deliverables are submitted, opened, reviewed and confirmed to meet the agreed acceptance criteria. - Screenshots, videos and renders alone are not accepted as final engineering deliverables. - Each milestone includes up to two reasonable requirement-related revision rounds. - If a milestone still fails the written acceptance criteria after those revisions, the client may terminate the remaining project and request cancellation or return of unreleased milestone funds through Freelancer.com’s applicable process. - Previously completed and formally approved milestones remain payable. - Uncompleted or unapproved future milestones will not be released. - Final payment only after all agreed editable CAD, STEP files, drawings, BOM, assembly instructions, test documentation and post-prototype revisions are delivered and verified. CONFIDENTIALITY AND OWNERSHIP - NDA required before confidential collar files are shared. - All paid and approved project-specific CAD, drawings, designs and engineering documents belong to the client. - Confidential project details may not be reused, sold, published or shared without written permission. APPLICATION REQUIREMENTS Please answer: 1. Describe one relevant project involving a small locking, spring, cable, pin or lever mechanism. 2. Explain your approach to a fail-locked emergency-release system. 3. Explain how you would manage excess mechanical cable across three leash lengths. 4. Which CAD software will you use? 5. Which editable files and documentation will you deliver? 6. Can you provide native editable CAD, not only STL? 7. Provide fixed price and estimated duration for each milestone. 8. Confirm NDA, ownership terms and two revision rounds per milestone. 9. Show your most relevant portfolio project. 10. Begin your proposal with “ALFA MECHANICAL”.
Project ID: 40587026
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18 freelancers are bidding on average $360 USD for this job

As a seasoned Mechanical Engineer with expertise in 3D Modelling, Solidworks, Manufacturing Design, and Prototyping, I am more than equipped to tackle the complex demands of your premium dog leash project. In my lengthy career, I have designed and developed various intricate mechanisms and have a comprehensive understanding of how each component works cohesively. Combining this expertise in CAD/CAM, Mechanical Engineering and my avid love for animals, I believe no one is better fit for this project than me. Coming down to the specifics of your leash emergency release system, it seems that my experience in designing finely integrated mechanisms that function effectively even under extreme conditions would be an asset. I am well-aware of the crucial role structural safety plays in a product such as this and can ensure that all functionalities align with your requirements while meeting strict security standards. Furthermore, I am highly knowledgeable about materials and their engineering properties - critical as you seek optimal ones for manufacturing.
$75 USD in 1 day
7.8
7.8

Hi there, I have extensive experience in mechanical product design, precision locking mechanisms, and prototype-ready CAD development using SolidWorks. I can help engineer a reliable fail-locked emergency release system with a strong focus on safety, manufacturability, serviceability, and robust mechanical performance. Approach: • Develop a fail-safe mechanical architecture with positive locking and controlled emergency release. • Design the cable routing, length-adjustment mechanism, and connector while minimizing wear and simplifying manufacturing. • Perform engineering calculations and prepare a practical validation and bench-testing plan before prototype release. Deliverables: • Native SolidWorks CAD, STEP, STL, detailed manufacturing drawings, BOM, and assembly instructions. • Engineering documentation, tolerance details, and prototype-ready design with revision support. I can sign the NDA, provide fully editable CAD files, and comply with the ownership terms and milestone-based workflow. Estimated duration and pricing can be finalized after reviewing the existing collar CAD and detailed requirements. Best regards, Arati M
$75 USD in 7 days
6.7
6.7

Give me one opportunity to handle your project. I have experience designing functional mechanical products with locking, spring, pin, lever, and cable-operated mechanisms, focusing on reliability, manufacturability, and prototype-ready CAD rather than visualization alone. My approach is to develop a fail-locked system where any cable or component failure keeps the leash safely locked, while ensuring smooth one-handed operation and serviceability. Excess cable will be managed inside a protected cartridge to maintain consistent travel across all three leash lengths. I will use **SolidWorks** to deliver native editable CAD, STEP, STL, detailed manufacturing drawings, BOM, assembly instructions, tolerance information, and a practical bench-test plan. I can provide fully editable native CAD files, not just STL. I am comfortable working under NDA, accept your ownership terms, and agree to two revision rounds per milestone. I can share my most relevant mechanical design portfolio upon request. I look forward to discussing milestone pricing and timeline.
$75 USD in 7 days
1.9
1.9

Hi, ALFA MECHANICAL I'd love to work on your project. I have experience designing precision mechanical products with locking mechanisms, spring-loaded assemblies, cable-actuated systems, and manufacturing-ready CAD for functional prototypes. My approach will focus on developing a robust fail-locked mechanism that prioritizes safety, durability, serviceability, and ease of manufacturing. I'll deliver the project in structured milestones, from feasibility and mechanical architecture through prototype-ready CAD, engineering drawings, BOM, assembly documentation, and post-prototype revisions. All native CAD files, STEP files, STL files, and complete documentation will be provided. I can work in SolidWorks and provide fully editable native CAD files. I confirm my acceptance of the NDA, ownership terms, milestone-based workflow, and two revision rounds per milestone. I'd be happy to discuss the milestone timeline and share similar mechanical product design projects from my portfolio. Best regards, Diksha L
$70 USD in 1 day
3.0
3.0

Hello, I am a Mechanical Design Engineer with experience in developing functional, manufacturing-ready products using SolidWorks. I specialize in mechanical mechanisms, DFM/DFA, prototype development, and engineering documentation. 1. I have designed products with spring-loaded locking, pin, and lever mechanisms for reliable operation. 2. My fail-locked design keeps the locking pin spring-biased in the locked position, so cable or mechanism failure cannot release the leash. 3. Excess cable will be managed using an internal cable-storage cartridge with controlled bend radius and consistent lever travel. 4. CAD: SolidWorks. 5. Deliverables: Native SolidWorks files, STEP, STL, PDF drawings, BOM, exploded views, assembly instructions, and test plan. 6. Yes, I will provide fully editable native CAD files. 7. Timeline: M1 (5–7 days), M2 (7–10 days), M3 (10–14 days), M4 (4–6 days), M5 (after prototype testing). Fixed price can be finalized after reviewing the collar CAD. 8. I confirm NDA, ownership transfer, and two revision rounds per milestone. 9. I can share my most relevant mechanism design project privately after NDA. I look forward to working with you.
$50 USD in 2 days
1.0
1.0

ALFA MECHANICAL, I bring expertise in mechanical design for complex locking mechanisms, with a focus on safety and reliability. Your project involves developing a sophisticated dog leash with emergency release features, which aligns with my background in safety-critical systems. I am experienced in designing load-bearing parts, cable routing, and fail-safe mechanisms, ensuring the leash remains secure under all conditions. I will utilize advanced CAD software for precise modeling and deliver comprehensive documentation, including manufacturing drawings and BOMs. My approach emphasizes robust testing plans and easy serviceability, addressing your requirements thoroughly. I am committed to NDA compliance and ownership transfer, with a clear plan for iterative revisions. My portfolio includes similar projects involving spring-loaded pins and cable management systems. I look forward to creating a reliable, prototype-ready design that exceeds your expectations. Please see my detailed plan below. Invent a pertinent question about the project's goals for the client.
$85 USD in 30 days
0.0
0.0

Not going to do the usual pitch thing. The emergency-release handle needs a protected lever with a guard. This ensures safety and prevents accidental release. Are you leaning towards a specific material for the handle or open to suggestions? What I'll do for you: - Feasibility assessment with architecture proposal - Preliminary CAD including assembly views - Prototype-ready CAD and STL files - Engineering documentation for manufacturing Even if you don't hire me I would love to chat and help you out where I can. Regards, K GumptionOps
$50 USD in 2 days
0.0
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Hello, ALFA MECHANICAL I reviewed your engineering brief, and the primary challenge is designing a fail locked emergency release mechanism where the load path, cable actuation, locking pin, and length adjustment remain completely independent so that no single mechanical failure can unintentionally release the leash. The feasibility phase should validate the mechanical architecture, force transmission, cable routing, wear points, serviceability, and manufacturing considerations before detailed CAD begins, ensuring the prototype is both safe and practical for production. I have worked on complex mechanical product development involving locking and actuation mechanisms and can share relevant engineering projects once we connect in chat. Also a quick question, have you already established the target static and shock load requirements that the locking pin and connector assembly must be engineered to withstand during bench testing? Best Regards, Atik
$60 USD in 1 day
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With an industry-spanning expertise in Mechanical and Product Design along with proficiency in 3D modeling via SolidWorks, I am excited to offer you my adept services. Growing into manufacturing-focused design principles and solutions has allowed me to find precise, creative approaches to complex engineering projects like this dog leash emergency release system. Constantly adhering to Design for Manufacturing (DFM) norms, I'll ensure the simplicity of your concept's realization without compromising on safety or functionality. My experience covers the gamut of design-production process from conception to manufacturing, which aligns seamlessly with your project requirements. . With regards to the specifics of this project, my extensive knowledge in materials and manufacturing processes including sheet metal design, rapid prototyping and CNC manufacturing assures you that your leash concept will be designed for utmost efficiency throughout its life-cycle. Furthermore, timely delivery is a promise I value. It will yield well-defined technical drawings which I have observed accounts for intricate yet serviceable components such as internal bushing, pin/spring cartridge, cylindrical connector head, control cable and sheath and are easily replicable for efficient maintenance. My aim is not only to
$50 USD in 1 day
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ALFA MECHANICAL Hello, I am a Mechanical Design Engineer with experience in SolidWorks, mechanical assemblies, engineering drawings, and product development. I also have an Electrical Engineering background, allowing me to approach projects from both mechanical and functional perspectives. 1. Relevant project: I designed a complete Gear Reducer Assembly in SolidWorks, including detailed parts, assembly, exploded view, and manufacturing drawings. I also developed an Electronic Voltage Monitoring Module with PCB design. 2. Fail-safe approach: I would use a spring-loaded locking mechanism where the pin remains locked by default. Any cable failure or damage would keep the leash safely locked. 3. Cable management: I would design an internal cable cartridge with guided routing and proper bend radius to ensure smooth operation at all three leash lengths. 4–6. CAD & Deliverables: SolidWorks. I provide editable SLDPRT/SLDASM files, STEP, STL, PDF drawings, BOM, assembly instructions, and exploded views. 7. Timeline: Available after reviewing the existing collar CAD files and project details. 8. I confirm NDA, ownership transfer, and two revision rounds per milestone. I look forward to discussing your project. Best regards, Yuriy Potapenko
$90 USD in 7 days
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ALFA MECHANICAL Your focus on a reliable emergency-release system paired with a premium adjustable leash is crucial for both safety and functionality. We specialize in designing mechanical systems that prioritize user safety and operational efficiency. With extensive experience in mechanical design and prototyping, I can ensure your product is not only safe but also manufacturable. We have 75+ 5-star reviews on similar projects and rank in the top 1% among 75 million users! What is your timeline for the initial prototype and testing phases? Regards, Hamza
$50 USD in 7 days
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ALFA MECHANICAL We recently helped a client achieve a successful prototype for a complex mechanical locking system — and judging by your post, it sounds like we could do the same for you. We've worked on mechanical designs for premium pet products and would love to bring that experience to your project. From your post, it sounds like you're looking for something safe, reliable, and user-friendly, specifically around the emergency-release handle and locking mechanisms. We specialize in mechanical design engineering and have 75+ 5-star reviews on similar projects, ranking in the top 1% among 75 million users! I would love to help you with your project! The worst that can happen is you walk away with a free consultation. Regards, Shannonkb21
$50 USD in 7 days
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Hello! We can develop a prototype-ready mechanical solution for this leash system. 1. Which part should we focus on first: the release mechanism, the connector, or the length adjustment? 2. Do you already have the collar CAD files ready to share under NDA? — About us We are dZENcode – a full-cycle IT company for digital product development: from design and programming to integrations and post-release support. We build projects from scratch and also work on existing solutions that need further development, improvements, or technical support. You can find detailed information about our services and rates on our official website: https://dzencode.com. Please review it – after that, we can discuss the details and agree on the next step. ⚠️ After clarifying all details, we will define the scope, the suitable cooperation format – task-based, outsourcing, or outstaffing – and the final cost. Projects are guaranteed to reach release with us: • 10+ years providing IT services; • 90+ in-house specialists; • 250+ public reviews since 2015; • We support products under SLA after launch; • We work under NDA and a company contract!
$75 USD in 7 days
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ucuz kaliteli ve yüksek kalitede bir köpek tasması tasarlayabilirim mühendisim bir kaç saatimi alır sizin isteklerinize göre sıınırsız revizasyon yapabiliriz
$75 USD in 1 day
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