Preamble
In my inbox was a newsletter from Designboom featuring an article on Twike a three-wheeler car electric car
Over the years since engineering school when I encountered Morgan, (my brother loves Morgans) and later in design school. I have always wondered when designing or creating three-wheeler cars why don’t Auto designers use a single wide wheel and tyre or the two standard tyres housed closely coupled in a single wheel assembly for the third single wheel for stability? In order to answer my question, I ventured down the rabbit hole .
Background
When designing three-wheeler cars, engineers and designers must carefully balance these factors to create vehicles that are safe, efficient, and appealing to consumers. The success of such vehicles often depends on their intended use case and target market. Designing or creating three-wheeler cars, also known as trikes or autocycles, comes with several advantages and disadvantages:
Advantages:
1. Improved fuel efficiency: Lower weight and reduced drag can lead to better fuel economy.
2. Manoeuvrability: Typically, more agile than four-wheeled vehicles, especially in tight spaces.
3. Reduced complexity: Fewer parts can mean simpler manufacturing and maintenance.
4. Stability: More stable than two-wheeled vehicles, particularly at low speeds or when stationary.
5. Unique design possibilities: Allows for innovative and eye-catching designs.
6. Lower production costs: Potentially cheaper to manufacture due to fewer components.
7. Regulatory advantages: In some regions, three-wheelers may be classified differently, leading to less stringent regulations.
8. Parking efficiency: Can often fit into smaller parking spaces.
9. Fun factor: Many users find them enjoyable to drive due to their unique handling characteristics.
10. Potential for specialization: Well-suited for specific uses like urban commuting or leisure driving.
Disadvantages:
1. Stability concerns: May be less stable than four-wheeled vehicles, especially at high speeds or during sharp turns.
2. Limited passenger and cargo capacity: Often smaller than traditional cars, limiting utility.
3. Safety perceptions: Consumers may perceive them as less safe than four-wheeled vehicles.
4. Regulatory challenges: Classification and safety standards can vary, potentially limiting markets.
5. Weather exposure: Some designs offer less protection from the elements compared to enclosed cars.
6. Limited market acceptance: May face scepticism from consumers used to conventional vehicles.
7. Performance limitations: Might not match the performance of four-wheeled vehicles in certain areas.
8. Tire wear: Uneven tire wear can be an issue, especially for the single wheel (front or rear).
9. Handling differences: Drivers may need to adjust to different handling characteristics.
10. Infrastructure compatibility: May not be optimally suited for existing road infrastructure designed for four-wheeled vehicles.
11. Limited options: Fewer aftermarket parts and customization options compared to conventional cars.
12. Resale value: – Potentially lower resale value due to niche market appeal.
What are the design considerations and requirements that impact the placement of the single wheel
The placement of the single wheel in a three-wheeler car (either at the front or rear) is a crucial design decision that significantly impacts the vehicle’s performance, handling, and overall characteristics. Each configuration has its pros and cons, and the final decision often depends on a balance of these factors along with the specific goals of the vehicle design. Engineers must carefully consider these aspects to create a three-wheeler that meets safety standards, performance targets, and market demands. The placement of the single tire, whether at the front or rear, influences the vehicle’s stability, handling, weight distribution, and overall performance. Designers must carefully weigh these factors to create a vehicle that meets safety standards, performance goals, and market expectations. Here are some key design considerations and impacts based on the single tire’s location:
Front Single Wheel Configuration:
Advantages:
1. Improved Aerodynamics: Placing the single wheel at the front can result in a more streamlined body design, potentially reducing drag.
2. Simplified Steering Mechanism: The steering mechanism can be simpler, akin to motorcycle steering, which might reduce complexity and cost.
3. Better Weight Distribution: Allows for better weight distribution if the engine and major components are located towards the rear, improving stability and handling.
4. Enhanced Manoeuvrability: Typically provides better manoeuvrability and a tighter turning radius, which is advantageous in urban environments and tight spaces.
Disadvantages:
1. Stability Concerns: Higher risk of forward rollover during hard braking, as the single front wheel bears significant load during deceleration.
2. Traction Limitations: May offer less traction during braking and steering, especially in low-traction conditions, since the single tire handles all the directional forces.
Rear Single Wheel Configuration:
Advantages:
1. Enhanced Stability: More stable when stationary or at low speeds, reducing the risk of backward rollover during rapid acceleration.
2. Better Traction for Acceleration: Rear placement can provide better traction during acceleration, particularly for rear-wheel-drive configurations.
3. Simplified Suspension Design: The front suspension can be simpler with the single wheel at the rear, reducing complexity and potentially cost.
4. Flexible Passenger and Cargo Placement: Allows for more flexible options for passenger and cargo placement, especially if the front wheels are used for steering.
Disadvantages:
1. Complex Steering System: Requires a more complex steering system, often involving both front wheels turning, which can increase design and manufacturing complexity.
2. Weight Distribution Challenges: May lead to uneven weight distribution if the engine is placed at the front, affecting handling and stability.
3. Aerodynamic Design Challenges: The rear single wheel may limit design options for a streamlined front end, potentially increasing drag.
4. Tire Wear: The single rear tire typically experiences more wear, especially during acceleration and cornering, which could lead to more frequent maintenance.
Impact on Design Choices:
1. Safety and Stability: Designers must consider the vehicle’s intended use and ensure that stability and safety are not compromised by the wheel placement. This includes analysing rollover risks, braking performance, and traction.
2. Performance and Handling: The location of the single tire affects the vehicle’s handling characteristics. For sporty or performance-oriented three-wheelers, front single-wheel configurations might be preferred for better manoeuvrability. For utility or commuter vehicles, rear single-wheel configurations could offer better stability and load-carrying capacity.
3. Aesthetics and Market Appeal: The visual appeal of the vehicle can be influenced by the wheel placement. Designers need to balance aesthetics with functionality to attract consumers while maintaining performance standards.
4. Regulatory and Legal Considerations: Different regions may have specific regulations that favour one configuration over the other. Designers must ensure compliance with these regulations to avoid market limitations.
5. Manufacturing Complexity and Costs: The complexity of the steering and suspension systems, as well as the overall vehicle structure, is influenced by the wheel configuration. Simplifying these systems can reduce manufacturing costs and improve maintenance ease.
6. Weight Distribution and Load Management: Proper weight distribution is crucial for vehicle stability and performance. Designers need to strategically place components like the engine, battery, and passengers to ensure balanced load management.
Probable outcomes of using a single wide wheel and tire or two standard tires closely coupled in a single wheel assembly
Auto designers typically don’t use a single wide wheel and tire or two standard tires closely coupled in a single wheel assembly for the third single wheel in three-wheeler cars due to several key considerations related to performance, safety, and design complexity. The traditional single narrow wheel for three-wheelers is a balance of simplicity, efficiency, and performance. While a single wide wheel or dual tires could offer some benefits, the trade-offs in terms of weight, rolling resistance, handling complexity, and cost make it less attractive for many automotive designers. Additionally, the unique handling characteristics and design flexibility of three-wheelers are often better served with the more conventional single narrow wheel setup. Implementing a wide single tire or dual-tire assembly in a three-wheeler design offers some potential benefits in terms of stability, traction, and load capacity. However, it also introduces significant challenges in terms of design complexity, cost, and potential market acceptance. The decision to use such a configuration would depend heavily on the specific goals of the vehicle design, target market, and intended use case.
Here’s an analysis of the potential advantages and disadvantages of this design approach for both front and rear configurations:
Front Single Wheel Configuration:
1. Steering and Handling:
– Advantage: Improved traction and stability during cornering.
– Disadvantage: Increased steering effort due to larger contact patch.
2. Suspension Design:
– More complex suspension system required to handle increased unsprung weight.
– Potential for improved ride quality due to larger tire volume.
3. Vehicle Dynamics:
– Better resistance to crosswinds and improved straight-line stability.
– Possibly reduced manoeuvrability in tight spaces.
4. Braking:
– Enhanced braking performance due to increased contact area.
– More complex brake system design may be necessary.
5. Aerodynamics:
– Potential increase in frontal area, leading to higher drag.
Rear Single Wheel Configuration:
1. Traction:
– Improved acceleration traction, especially beneficial in rear-wheel drive setups.
– Better stability under heavy loads or during braking.
2. Weight Distribution:
– Increased rear weight could improve weight distribution in front-engine designs.
– May necessitate chassis redesign to balance weight effectively.
3. Suspension and Drivetrain:
– More complex rear suspension design required.
– Potential challenges in integrating with the drivetrain, especially for rear-wheel drive systems.
4. Stability:
– Enhanced lateral stability, potentially reducing the risk of fishtailing.
– May affect the vehicle’s tendency to understeer or oversteer.
5. Cargo Capacity:
– Could impact rear cargo space design.
General Considerations for Both Configurations:
1. Tire Selection and Availability:
– Limited options for specialized wide or dual-tire assemblies.
– Potential increase in replacement costs.
2. Vehicle Width:
– May increase overall vehicle width, affecting parking and manoeuvrability.
3. Regulatory Compliance:
– Could affect vehicle classification and regulatory requirements.
4. Cost:
– Higher manufacturing and maintenance costs due to non-standard components.
5. Consumer Perception:
– Unique appearance might appeal to niche markets but could deter mainstream buyers.
6. Performance Trade-offs:
– While offering better stability and traction, the increased weight and rolling resistance could negatively impact acceleration and fuel efficiency.
7. Ride Comfort:
– Potential for improved ride quality due to larger tire volume, but this depends on suspension tuning.
The Future: What are the opportunities offered by hybrid or battery engines for the design of three-wheeler cars
Hybrid and battery electric powertrains offer significant opportunities for innovative three-wheeler car designs. These technologies can address some traditional limitations of three-wheelers while enhancing their inherent advantages. These opportunities not only address some of the traditional challenges associated with three-wheeler designs but also open up new possibilities for innovation in urban mobility, personal transportation, and utility vehicles. The combination of three-wheel design with electric or hybrid powertrains can create highly efficient, manoeuvrable, and environmentally friendly vehicles suited for a variety of applications. Here are some of the key opportunities:
1. Weight distribution: Battery placement flexibility allows for optimal weight distribution, improving stability and handling. Compact electric motors enable more design freedom for overall vehicle layout.
2. Lower centre of gravity: Batteries can be placed low in the chassis, reducing rollover risk and improving cornering stability.
3. Improved performance: Electric motors provide instant torque, enhancing acceleration and hill-climbing ability. Regenerative braking can improve overall efficiency and range.
4. Simplified drivetrain: Fewer moving parts in electric powertrains can reduce maintenance needs and increase reliability. Direct drive systems can eliminate the need for a traditional transmission.
5. Enhanced stability control: Electric powertrains allow for precise power delivery to wheels, enabling advanced traction and stability control systems.
6. Noise reduction: Quieter electric operation can make three-wheelers more appealing for urban use.
7. Energy efficiency: Electric and hybrid powertrains can significantly improve fuel efficiency, especially in stop-and-go traffic.
8. Design flexibility: Compact electric components allow for more creative body designs and interior layouts. Opportunity for modular designs that can be easily customized.
9. Urban mobility solutions: Low emissions make them ideal for cities with strict environmental regulations. Compact size combined with electric power suits last-mile delivery and short urban trips.
10. Range extension: Hybrid systems can offer extended range compared to pure battery electric vehicles.
11. Charging infrastructure compatibility: Can leverage existing and growing EV charging networks.
12. Smart technology integration: Electric architecture facilitates the integration of advanced driver assistance systems and connectivity features.
13. Renewable energy compatibility: Can be easily integrated with home solar systems or other renewable energy sources for charging.
14. Thermal management: Electric systems generate less heat, simplifying cooling system design.
15. Torque vectoring: In dual-motor configurations, electronic torque vectoring can enhance handling and stability.
16. Regulatory advantages: May qualify for EV incentives and access to restricted urban areas.
17. Cost-effective production: Simplified powertrains can potentially reduce manufacturing costs.
18. Customizable performance: Software-controlled powertrains allow for easy customization of performance characteristics.
19. Vehicle-to-grid capabilities: Potential for the vehicle to serve as a mobile power source or grid storage unit.
20. Aerodynamic improvements: Electric powertrains allow for smoother underbody designs, improving aerodynamics.
Initial Thoughts
My take aways after surfacing from the rabbit hole:
- Tyre design: There is scope for innovation in terms of tyre design. My question was partially answered but further considerations for the suggestion of two standard tyres housed closely coupled in a single wheel assembly without violating the concept of a three-wheeler will need modelling to address some issues such as complex suspension system, steering, cost, and weight etc.
- Stability of the three-wheeler design: The increased use of sensors and software might introduce some innovations like the emergency deployment of stabilisation micro tyres or the use of new gyroscopes, and anti-roll over technology.
- Open-source platform: Due to the form factor there is an opportunity to create an affordable\ flexible world platform for hybrid or electric powered (city) three-wheel car with the design released as an open-source resource with all the minimum technology, material science and production specifications \ technology (see appendices)? This could work as a future replacement for the auto rickshaw which is a motorized version of the pulled rickshaw or cycle rickshaw. Most have three wheels and do not tilt used mainly in Asia and Africa. The open-source platform will have to be adaptable for multiple implementations: Engine type, Safety, Cost, Materials, Technology and Sustainability etc.
- What are the opportunities for rental car services that mimic the ride sharing services with city parking spaces and creation single seaters for load carrying.
- Materials: There is the opportunity to use new sustainable materials for three-wheelers, an example will be a modular design with a choice of panels.
- Production automation: for the more developed countries have we reached the stage where the production of the three wheelers can aspire to reach 80-90% robotic process\ production automation (see appendices)?
Conclusion
Was this exercise worth it? I don’t know if it provided a precise answer but I learnt a lot and found multiple novel ideas below which might overlap with my initial thoughts above for three-wheelers:
1. Adaptive Suspension Systems: Integrate advanced adaptive suspension systems that can automatically adjust based on road conditions and driving dynamics, improving stability and comfort for three-wheelers.
2. Enhanced Safety Features: Incorporate state-of-the-art safety features such as advanced driver assistance systems (ADAS), including lane-keeping assist, automatic emergency braking, and collision avoidance technology.
3. Modular Designs: Develop modular three-wheeler platforms that allow for easy customization and scalability. This could cater to different market needs, from urban commuters to recreational vehicles.
4. Solar Integration: Explore the integration of solar panels on the vehicle’s surface to provide supplementary power, increasing overall energy efficiency and reducing dependency on charging infrastructure.
5. Smart Connectivity: Implement smart connectivity features, such as real-time navigation updates, remote diagnostics, and vehicle-to-vehicle (V2V) communication, to enhance the driving experience and safety.
6. Lightweight Materials: Use advanced lightweight \ composite materials like Carbon fibre, Hemp, Recycled materials to reduce the vehicle’s weight, further improving fuel efficiency and performance.
7. Battery Swapping Stations: Promote the development of standardized battery swapping stations to reduce downtime for electric three-wheelers, making them more practical for long-distance travel.
8. Shared Mobility Solutions: Develop three-wheelers specifically designed for shared mobility services, such as ride-sharing and micro-mobility platforms, addressing the growing demand for sustainable urban transportation.
9. User-Centric Design: Focus on ergonomic and user-centric design elements to enhance comfort, accessibility, and ease of use for a broader range of consumers, including those with mobility challenges.
10. Sustainable Manufacturing: Emphasize sustainable manufacturing practices, such as using recycled materials and reducing waste, to create eco-friendly three-wheelers that align with environmental goals.
11. Use of small\ micro engines for the hybrid engines: The technology is quite mature especially as deployed in Japan’s Kei Cars. The standards for size, the user experience and outcomes will provide valable input to an open source platform.
12. Responding to demand: Can multiple three wheelers be transported on trains or specialised trucks to respond to demand across a region, city or country.
Appendices
Some Three-wheeler cars: non-exhustive list:
- Aptera ,
- Carver Electric
- Morgan
- 10 cars that only had three wheels
- 15 Best and Incredibly Awesome Three-Wheeled Vehicles
- Three-wheeled motor vehicles
The percentage of a car that can be assembled by robots
The percentage of a car that can be assembled by robots varies depending on the manufacturer, the specific model, and the level of automation in the production facility. These figures are approximate and can change rapidly as technology advances. For the most current and specific information, it would be best to check with individual automakers or industry reports, as automation levels can vary significantly between manufacturers and even between different models produced by the same company. A general overview of the current state of robotic automation in car manufacturing (needs further confirmation and references):
As of 2024, a significant portion of car assembly can be done by robots, but the exact percentage varies widely. Here’s a breakdown:
1. Body Assembly: 80-100% – Welding, painting, and major body assembly are highly automated.
2. Powertrain Assembly: 60-80% – Engine and transmission assembly have high levels of automation.
3. Interior Assembly: 30-50% – This area still requires significant human involvement due to the complexity and variety of tasks.
4. Final Assembly: 20-40% – Many final assembly tasks still require human dexterity and decision-making.
Overall industry estimates:
– On average, around 50-70% of the total assembly process can be automated in modern car manufacturing plants.
– Some highly advanced facilities claim automation levels up to 90% for certain models.
– Tesla’s Fremont factory, known for its high automation, reportedly achieved about 75% automation in body manufacturing.
Key factors influencing automation levels:
1. Complexity of the vehicle model
2. Production volume
3. Investment in automation technology
4. Labor costs in the manufacturing location
5. Required flexibility in production lines
It’s important to note that:
– Full automation is not always desirable due to the need for flexibility and quality control.
– Human workers are still crucial for complex assembly tasks, quality checks, and problem-solving.
– The trend is towards increasing automation, but with a focus on collaborative robots (cobots) that work alongside humans.
Open-source platform for designing and producing affordable hybrid or electric three-wheelers
Creating an open-source platform for designing and producing affordable hybrid or electric three-wheelers involves several critical steps. These steps will include a combination of technological, community-building, and strategic initiatives to ensure the platform’s success. By following a structured pathway, the goal of creating an affordable, open-source hybrid or electric three-wheeler can be achieved, fostering innovation and providing sustainable transportation solutions globally. Here’s a framework and pathway for achieving this:
1. Initial Planning and Vision
Define Objectives:
– Develop a clear vision for the platform.
– Establish goals such as affordability, sustainability, and accessibility.
2. Core Platform Development
Open-Source Licensing:
– Choose an appropriate open-source license (e.g., GPL, MIT) to ensure that designs and technologies remain freely available and modifiable.
Platform Infrastructure:
– Set up a central repository (e.g., GitHub, GitLab) for design files, documentation, and collaboration tools.
3. Design and Engineering
Basic Vehicle Design:
– Develop initial design prototypes using CAD software.
– Focus on modular designs that can be easily customized and manufactured.
Technological Specifications:
– Define minimum technology requirements such as battery capacity, motor specifications, and control systems.
– Use standard and widely available components to ensure accessibility and reduce costs.
4. Material Science and Production Specifications
Sustainable Materials:
– Research and select sustainable materials that can be used in manufacturing.
– Ensure materials are durable, lightweight, and cost-effective.
Manufacturing Processes:
– Document manufacturing processes, focusing on methods that are accessible to small manufacturers and DIY enthusiasts.
– Include detailed instructions for both manual and automated production methods.
5. Community Building and Collaboration
Online Community:
– Create an online community for developers, engineers, and enthusiasts to collaborate, share ideas, and contribute to the project.
– Use forums, social media, and regular virtual meetings to engage the community.
Collaborative Development:
– Encourage community contributions through hackathons, design competitions, and collaborative projects.
– Implement a review and approval process for community contributions to ensure quality and coherence.
6. Prototyping and Testing
Prototype Development:
– Develop and test multiple prototypes to refine designs.
– Use feedback from the community and real-world testing to improve the vehicles.
Safety and Compliance:
– Ensure prototypes meet safety standards and regulations for the target markets.
– Document compliance procedures and provide guidelines for testing and certification.
7. Production and Distribution
Manufacturing Partnerships:
– Form partnerships with manufacturers to produce vehicle components, kits and complete units.
– Explore decentralized manufacturing to enable local production and reduce shipping costs.
Distribution Network:
– Develop a distribution network that can handle orders and deliver vehicles efficiently.
– Consider partnerships with existing logistics companies and setting up regional distribution centres.
8. Support and Maintenance
User Support:
– Provide comprehensive documentation, including assembly guides, maintenance manuals, and troubleshooting tips.
– Set up a support system for users, including community forums and a helpdesk.
Spare Parts and Upgrades:
– Ensure availability of spare parts and upgrades.
– Encourage community-driven development of aftermarket parts and enhancements.
9. Funding and Sustainability
Crowdfunding and Grants:
– Launch crowdfunding campaigns to raise initial funds for development and production.
– Apply for grants from governmental and non-governmental organizations supporting sustainable transportation.
Business Model:
– Develop a sustainable business model, such as offering premium versions or kits, licensing manufacturing rights, or providing consulting services.
10. Continuous Improvement and Expansion
Feedback Loop:
– Implement a continuous feedback loop to gather user experiences and data for ongoing improvement.
– Regularly update designs and documentation based on feedback and technological advancements.
Expansion:
– Explore opportunities to expand the platform to include other types of vehicles or new markets.
– Keep the platform adaptable to incorporate future technologies and innovations.
