The problem
E-rickshaws carry many passengers in Indian cities, yet cabins are often built without measured layouts: high steps, hard edges, poor grab handles and cramped legroom. Elderly passengers and people with limited mobility find boarding hard. A measured, drawn cabin layout is a practical improvement students can make.
Objectives
- Lay out seating, legroom, headroom and step height for small and large passengers.
- Model the cabin frame with Weldments and the seats with Sheet Metal.
- Place grab handles and a step for safe boarding, including for elderly users.
- Produce drawings, a weight estimate and an accessibility checklist.
What you need
Tools and toolboxes
- SOLIDWORKS Weldments — Roof frame and seat frames built from structural members with trim and cut lists.
- SOLIDWORKS Sheet Metal — Seat pans, step and floor panels with bend allowances and flat patterns.
- SOLIDWORKS Assembly and Interference Detection — Cabin assembly with passenger manikin bodies and chassis envelopes.
- Mass Properties — Cabin weight and centre-of-mass position with and without passengers.
- SOLIDWORKS Drawings — Layout drawing, cut list and flat-pattern drawings.
Software
- SOLIDWORKS 2023 or later
- Excel for anthropometric data and the checklist
Extra parts and data
- A reference e-rickshaw to measure — Measuring an existing vehicle gives a realistic baseline for legroom and step height.
- Published anthropometric data — Passenger sitting height, knee height and buttock-knee length set the cabin dimensions.
Key concepts
- Seat reference point
- A defined point on each seat from which legroom, headroom and knee clearance are measured, so layouts can be compared.
- Step height
- The vertical rise from ground to the first step and then to the floor. Lower, evenly spaced steps make boarding easier for elderly passengers.
- Cut list
- A Weldments table listing every member with its profile and length, used for purchasing and fabrication.
- Centre of mass
- Passenger and cabin positions change the vehicle's centre of mass, which affects stability on turns.
Step-by-step guide
- 1
Collect requirements and baseline
Measure an existing e-rickshaw if possible: seat height, seat depth, legroom, roof height, step heights and grab-handle positions. List requirements for an example four-passenger rear cabin and driver seat, and note that the vehicle must meet the current CMVR requirements and relevant AIS documents for e-rickshaws, which you should check. Tabulate sitting height, knee height and buttock-knee length for small and large example passengers from a published source.
Checkpoint: A baseline measurement table and a requirements table with sources.
- 2
Draw the cabin layout
In a layout sketch, draw the chassis floor line, wheel arches, battery box under the seat and the driver partition. Place seat reference points for each passenger and the driver. Add sketched passengers from your data for the small and large example. Dimension legroom from the front of the seat cushion to the facing obstacle, headroom from the seat to the roof and the step heights. Drive key dimensions with global variables.
Checkpoint: A fully defined layout sketch where the large passenger has headroom and knee clearance meeting your targets.
- 3
Model the roof frame
Create 3D layout sketches for the roof pillars, roof rails and cross members, then insert Weldment structural members using a square tube profile from the library or a custom profile you define. Use Trim/Extend for clean joints and add gussets and end caps. Leave mounting points for the roof panel and side curtains. Update the cut list and check member lengths.
Checkpoint: The frame rebuilds with a complete cut list and no overlapping members at the joints.
- 4
Design seats and floor
Model seat pans and backrests as Sheet Metal parts with a stated bend radius and K-factor, folded flanges for stiffness and holes for cushion fixings. Model the floor panel with a chequer-plate appearance and drain holes. Add a battery access hatch under the seat. Generate flat patterns to confirm each part can be cut from standard sheet sizes. Keep fixing holes on a common pitch so cushions from one supplier fit every seat.
Checkpoint: Each sheet metal part flattens without errors and fits within a standard sheet size you state.
- 5
Plan boarding and grab handles
Design the step as a sheet metal tread with a non-slip pattern. Aim for low, even step rises and a tread depth that fits a full foot, with values you justify from the data. Place vertical and horizontal grab handles so a passenger can hold one while stepping in and while seated. Check the reach from the ground to the first handle for the small passenger.
Checkpoint: Step rises are even and within your target, and the first grab handle is within reach of the small passenger standing on the ground.
- 6
Check clearances
Convert the passenger sketches into thin bodies or simple solid manikins and insert them into the assembly in sitting and boarding positions. Run Interference Detection against the frame, seats and handles. Check head clearance to the roof rail when boarding and knee clearance between facing seats. Round hard edges near heads and knees with fillets or padding envelopes. Check the driver partition too, since rear passengers' knees often meet it during braking.
Checkpoint: Interference Detection passes for all manikin positions and every edge near a head or knee has a stated radius or padding.
- 7
Estimate mass and centre of mass
Assign steel to the frame and sheet parts and an estimated mass to cushions. Use Mass Properties to find cabin mass and its centre of mass. Add point masses for example 65 kg passengers in each seat using simple bodies with overridden mass, and compare the centre of mass empty and fully loaded. Note the lateral shift with all passengers on one side.
Checkpoint: A table of cabin mass and centre of mass for empty, full and one-side-loaded cases.
- 8
Accessibility review
Write an accessibility checklist covering step height, handle reach, seat height for sitting down and standing up, space for a walking stick or bag, contrast colour on step edges and handles, and a priority seat near the entrance. Score the baseline vehicle and your design against it. Where possible, ask two or three elderly volunteers to try a mock-up step and handle at your dimensions.
Checkpoint: A completed checklist comparing baseline and new design, with any volunteer feedback recorded.
- 9
Drawings and report
Produce a layout drawing with the key ergonomic dimensions, a weldment drawing with the cut list, and flat-pattern drawings for seats and step with ISO 2768 general tolerances. Render the cabin to show the boarding area. Write a report with the baseline, requirements, layout, clearance and mass results and the accessibility checklist, and list what needs physical testing. Include the accessibility checklist as a one-page appendix that a fabricator or operator can follow.
Checkpoint: A report with complete drawings, cut list, clearance evidence and the accessibility comparison.
Testing & validation
- Legroom, headroom and step heights meet stated targets for both passenger sizes.
- Interference Detection passes for seated and boarding manikins.
- Sheet metal parts flatten and the cut list is complete.
- Accessibility checklist shows improvement over the baseline.
Expected results
A measured e-rickshaw cabin layout with frame, seats and boarding aids, clearance checks, mass and centre-of-mass data, drawings and an accessibility comparison with an existing vehicle.
Take it further
- Run a static study of the roof frame for a rollover-type load you define.
- Design a fold-out ramp or lower step for wheelchair users.
- Add rain curtains and a roof drain and check water flow paths.
Viva and review questions
Why check both small and large passengers?
The small passenger sets reach to handles and step height, while the large passenger sets headroom and knee clearance. A layout must satisfy both.
How did you get the cut list?
Weldments generates it automatically from the structural members, with profile and length for each, and I checked lengths after trimming the joints.
What did the accessibility review change?
It led me to lower and even out the step rises, add a vertical handle at the entrance and mark step edges with a contrast colour.
Learn it at DIYguru
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