Inclusive & Assistive Products
ISDN2001/2002: Second Year Design Project
Individual Research
By LU Yan (Lucy)
This research will study overall wheelchair design to meet standard wheelchair parameter and position of each component to improve the flexibility and user experience of PikaPilot wheelchair
Background
Our team plans to utilize four independent wheels to create a more versatile wheelchair capable of navigating narrow spaces, such as doorways and tunnels, in users' daily lives. This requires a complete redesign of the wheelbase and the wheelchair to accommodate these new wheels while supporting a weight capacity of at least 80 kg, necessitating a wheelbase structure that can withstand a holding force of at least 800 N. Apart from a robust frame, I am trying to design a wheelchair that closely aligns with the parameters of standard models on the market, such as ISO 7176 standard, to enhance user experience.
My ultimate goal is to effectively integrate each component and provide a comprehensive conclusion on an enhanced design for the new wheelchair. Additionally, I need to plan the positioning of each component and ensure the integration of all subsystems, including the four wheels, footrest, monitor, LiDAR, joystick, emergency stop (e-stop), chair, and footrest.
Research Question
How can I minimize the size of the wheelbase while ensuring stability, loading capacity, and manoeuvrability? Additionally, how can I integrate all components and subsystems to ensure compliance with the ISO 7176 standard?
Design Process
To meet the standard wheelchair requirement, there are some limitations of the hight and size. I adjust the height of seats by using customize profile instead of original long chair leg to modify the heigh.
Here is the comparison with standard wheelchair in dimension and centre of mass.
Frame structure design
Since the 4 big wheels has one more motor to control the raw instead of direct Drive Wheels, the wheels must be mount vertically, therefore here is the frame structure design. Additionally, the wheelchair is required to support a target static load of 35 kg, along with a human load of 110 kg, ensuring that the wheelbase can withstand these requirements. Meanwhile, the design has to maintain wheelBase's stability and manoeuvrability.
4mm Glass fibre Plate as connection with tolerance +0.2mm for holes and 3dp.
Using Stainless Steel Angle Bracket and 4mm gfp, with m5 screw to lock them with Aluminium profile together
Graph showing Stress Distribution Direction
Significance of Research
This research aims to develop a more user-friendly wheelchair by redesigning its components to enhance flexibility and movability of the wheelchair. By integrating four independent wheels and cooperate with software decision by mounting hardware on it, the wheelchair will be better equipped to navigate narrow spaces, such as doorways and tunnels, improving the daily experiences of users.
It is essential to compare the parameters with existing standard wheelchair as a reference, so that I could notice what can be improve from previous version especially in its centre of mass and component position. The project will involve assembling a physical wheelchair prototype to further software testing and validation of the new concept. By analysing existing wheelchairs on the market and incorporating user feedback, this research will contribute to a more effective and adaptable wheelchair design.