The problem
Shared electric vehicles are growing in Indian cities, but high steps, narrow doors, poor handles and no wheelchair space exclude many elderly and disabled people. Inclusive design needs evidence from the users themselves, not assumptions. Research that ties user needs to measured design changes can improve vehicle codes and products.
Objectives
- Identify barriers through interviews and observation with elderly and disabled users.
- Translate findings into measurable design requirements for boarding, seating and securing mobility aids.
- Design an accessible cabin in SOLIDWORKS and style it in Alias.
- Build a full-size mock-up and measure boarding time, effort and satisfaction against a baseline vehicle.
What you need
Tools and toolboxes
- SOLIDWORKS Part, Assembly and Weldments — Cabin structure, seats, ramp or low step, handles and wheelchair space in a parametric layout.
- SOLIDWORKS Motion or assembly mates — Animating a fold-out ramp or lift step and checking its range and clearances.
- SOLIDWORKS Simulation (Static) — Checking ramp and handle strength under stated loads.
- Autodesk Alias — Exterior and interior styling of the accessible design with clear visual cues.
- SOLIDWORKS Drawings — Mock-up build drawings and the final layout drawing.
Software
- SOLIDWORKS 2023 or later
- Autodesk Alias 2024 or later
- A statistics package and qualitative analysis tools (spreadsheets suffice)
Extra parts and data
- Full-size mock-up materials (timber, aluminium profiles, plywood) — Users must try the design physically before conclusions can be drawn.
- Wheelchair and walking aids for trials — Needed to test the ramp, space and securing points realistically.
- Ethics approval and partner organisations — Research with elderly and disabled participants needs approval and safe recruitment.
Key concepts
- Inclusive design
- Designing so that the widest range of people can use a product without special adaptation, with extreme users helping to reveal problems.
- Boarding effort
- How hard it is to get in, measured by time, assistance needed, handle force or a rated effort scale.
- Accessibility provisions in vehicle codes
- Indian bus body codes such as AIS-052 include accessibility provisions for buses; check the current revision and what applies to smaller vehicles.
- Mixed methods
- Combining qualitative findings from interviews with quantitative measurements from trials to support design decisions.
Step-by-step guide
- 1
Frame the research and get approval
Define the vehicle class, for example a shared e-rickshaw or a small e-shuttle, and the user groups: elderly people, wheelchair users and people with visual or hearing impairments. Write research questions and a study plan, and get approval from your institute's ethics committee. Partner with an organisation that works with these groups for safe recruitment and informed consent in accessible formats.
Checkpoint: Ethics approval, a recruitment plan with a partner organisation and accessible consent forms.
- 2
Study the baseline
Observe and video, with consent, users boarding and riding existing vehicles. Measure step heights, door widths, handle positions, seat heights and floor space of the baseline vehicle. Interview users about barriers and fears. Code interview transcripts into themes. Combine observations and measurements into a barrier list ranked by how many users mentioned each and how severe it was. Store recordings securely and anonymise transcripts as your ethics approval requires.
Checkpoint: A measured baseline vehicle, coded interview themes and a ranked barrier list.
- 3
Write measurable requirements
Turn each barrier into a requirement with a target value, such as a maximum step height, minimum clear door width for a wheelchair, handle diameter and position range, wheelchair space dimensions and a priority seat height. Check targets against available anthropometric data, accessibility codes such as the provisions in AIS-052 for buses, and the CMVR rules for your vehicle class, noting that current revisions must be checked.
Checkpoint: A requirements table where each requirement links to a barrier, a target value and its source.
- 4
Develop concepts in CAD
Build a parametric layout in SOLIDWORKS with the chassis, battery envelope and cabin. Develop two or three concepts, for example a low floor with a fold-out ramp, a side-entry lift step, and a rear-entry layout. Use Weldments for the frame and simple bodies for seats and wheelchair envelopes. Check each concept against the requirements table with measurements in CAD. Keep each concept in its own configuration so the scoring always uses the latest geometry.
Checkpoint: Concept configurations, each scored against every requirement with a measured value.
- 5
Check mechanisms and strength
Model the ramp or lift step with hinge mates and animate it in a motion study, checking deployed angle, stowed position and clearances with Interference Detection. Run static studies on the ramp under a stated wheelchair-plus-user load and on handles under a stated pull force. Compare with hand calculations and stated factors of safety. These are design checks, not certification.
Checkpoint: Mechanism clearances pass and static results meet the stated factor of safety and agree with hand calculations.
- 6
Style in Alias
Import the chosen layout into Alias and style the exterior and interior, keeping the measured openings, step and handle positions locked. Use contrast colour and form to make entry points, handles and the priority seat easy to see. Build surfaces with Skin and Rail, blend with Surface Fillet and check visible surfaces with Zebra and Continuity. Render key views in VRED or KeyShot.
Checkpoint: A styled model that keeps every accessibility dimension and passes continuity checks on visible surfaces.
- 7
Build the mock-up
Produce build drawings of a full-size mock-up of the boarding area, seats, handles and wheelchair space. Build it with timber and aluminium profiles, with adjustable step and handle positions. Measure the built mock-up against the CAD and record differences. Make sure it is strong and stable enough for safe trials, and have a supervisor or technician inspect it. Fit handles and steps with removable fixings so they can be moved between trial rounds.
Checkpoint: A safety-inspected mock-up whose key dimensions match the CAD within a stated tolerance.
- 8
Run comparative trials
Ask participants to board, sit and alight from the baseline vehicle and the mock-up, in a randomised order, with support staff present. Record boarding time, need for assistance, handle use, a rated effort score and satisfaction. Interview participants after each trial. Keep sessions short and stop if anyone is uncomfortable. Record wheelchair securing time where relevant. Note any assistance given and by whom, since needing help is itself an important outcome for these users.
Checkpoint: A complete dataset of times, effort ratings and interview notes for each participant and condition.
- 9
Analyse and iterate
Compare baseline and mock-up using suitable statistical tests for small samples, such as the Wilcoxon signed-rank test, and analyse interview notes for new themes. Change step height, handle positions or ramp angle on the mock-up and re-test with a smaller group if results show problems. Update the CAD and Alias models with the final values. Report effect sizes alongside p-values, since small samples can hide practically important differences. Keep the original and revised dimensions in one table.
Checkpoint: Statistical results with effect sizes, a list of design changes and an updated CAD model.
- 10
Report and propose guidelines
Write the thesis chapter or paper covering research questions, methods, baseline findings, requirements, design, mock-up trials and results. Propose a set of design guidelines with target values for accessible shared EVs of this class, and state how confident you are in each. Discuss limits such as sample size and the static mock-up. Share findings with the partner organisation and participants.
Checkpoint: A report and a guideline table with values, evidence and confidence for each guideline.
Testing & validation
- Ethics approval and informed consent for all participants.
- Measured baseline and mock-up dimensions against CAD.
- Static checks with hand calculations for ramp and handles.
- Statistical comparison of boarding time and effort between baseline and new design.
Expected results
An accessible shared EV cabin design backed by user research, CAD and Alias models, a tested full-size mock-up, measured improvements over a baseline vehicle and a draft set of design guidelines.
Research angle for your PhD
The research contribution is evidence linking specific dimensions, such as step height, handle position and ramp angle, to measured boarding time and effort for elderly and disabled users of shared EVs in Indian conditions. Mixed methods, a baseline comparison and a guideline table with confidence levels make the work suitable for design and transport accessibility journals, and useful for code committees.
Take it further
- Test the design in a moving vehicle trial on a closed course.
- Add audio and tactile wayfinding cues and test them with visually impaired users.
- Study the cost and mass impact of accessibility features.
Viva and review questions
Why involve users rather than relying on anthropometric data?
Data tell you body sizes, but not how people with limited strength, balance or vision actually board or what they fear. Observing and testing with users reveals barriers the data miss.
Why a mock-up instead of a full prototype vehicle?
A mock-up is cheaper, safer and adjustable, so we could test several step and handle positions quickly. It cannot show dynamic effects, which I note as a limit.
Which test did you use and why?
The Wilcoxon signed-rank test, because each participant tried both conditions and the sample was small and not clearly normally distributed.
How did ethics shape the method?
It required informed consent in accessible formats, support staff during trials, short sessions and the right to stop at any time.
Learn it at DIYguru
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