TBD
Vehicle Design
The HPV project was divided into subsystems to manage the workload of the whole project. There is a total of three subsystems: frame, drivetrain, and fairing. The frame subsystem deals with the internal structure of the HPV. This is the foundation for which everything is then built upon; it provides the main support of the vehicle and also deals with the design of the seating. The drivetrain subsystem focuses on how to convert human power to the movement and the handling of the vehicle. This includes the braking and steering system of the vehicle. The fairing subsystem is what provides the HPV some protection while also giving some aerodynamic properties to protect against air resistance and comfort for the rider in the vehicle. These three subsystems combined together will function to give performance as the main priority while still being safe to use.
Subsystem-Frame
The proposed frame design is a reclined tadpole design with two front wheels and one rear wheel. The tadpole design was chosen due to its ability to have a better capability of turning, its aerodynamic design, and stability [7]. Also the choice of having two wheels in the front instead of the back will offer better overall braking because we must have front wheel breaks. The proposed frame will have a stable rollover protection system (RPS) in the incident of a rollover. Designed for ergonomics, the vehicle will have laterally adjustable seating to accommodate all riders.
Subsystem-Drive Train
For the drivetrain, the proposed design will have a internally geared rear hub, multiple gear crankset, and direct steering system. An internally/planetary geared crankset would eliminate the need for a chain tension compensation while at the same time maintain the ability to have multiple gears at the front of the vehicle [8]. The indirect steering system lacks a sharper steering angle because of the insufficient travel since the whole assembly is located under the vehicle. The direct steering system could be used to accommodate for this problem because it would have the spatial freedom since it is mounted above the vehicle also it would be a simpler design [9]. For the brake system, our team proposed to have an anti-lock brake system, but a disk braking system may be used because attaching a rim brake would require a mount to a fork similar to traditional road bicycles. Forks would also affect the manufacturing simplicity that comes with a direct steering system. Another thing is, disc brakes offers a better clamping force with less influence from the terrain, weather, and wheel material [10].
Subsystem-Fairing
The proposed fairing system comprises of a removable front fairing and a back fairing. A fairing is necessary to reduce aerodynamic drag as the vehicle moves through the air. Once a vehicle reaches a certain speed, air resistance plays a major factor for the total force acting to slow the vehicle down [9]. This means that more power would be needed to drive the vehicle forward at that speed. A well-designed fairing allows the rider to drive the vehicle with less force as compared to one without a fairing. The shape of a back fairing also redirects the airflow around the vehicle and increases the air pressure exerted on its rear, creating a forward push force on vehicle [11].
