Compact Electric Car Exterior Concept Model in Alias

The problem

Electric car platforms change proportions: a flat battery floor raises the seating, a short front overhang is possible without an engine, and cooling needs differ. A student concept that ignores these factors is not convincing. Working from a credible package to a clean concept surface model teaches the link between engineering hard points and form.

Objectives

• Define a package with wheelbase, track, battery floor, occupants and ground clearance for an example compact EV.
• Explore proportions and stance with sketches and quick 3-D volumes.
• Build a concept surface model with body side, roof, front and rear, using symmetry and clean curve networks.
• Check highlights, proportions and package clearance.
• Produce renders and a short design review presentation.

What you need

Key concepts

Skateboard platform

A flat floor-mounted battery between the axles, with motors at one or both axles, which raises the floor and frees the front and rear.

Proportions

Relationships such as wheel size to body height, overhangs, dash-to-axle distance and greenhouse height that set a car's character before details.

H-point

The hip point of a seated occupant. It sets eye height, headroom and roof height, and in EVs is raised by the battery floor.

Feature line

A deliberate crease or change in surface direction that catches light and defines the body side.

Step-by-step guide

1. 1

   Set the package

   For an example compact EV with a 2500 mm wheelbase, 3800 mm length, a 120 mm thick battery floor and 16-inch wheels, draw side, top and front package views. Place occupants by H-point, head clearance and eye point, and include ground clearance, approach and departure angles, wiper and lamp positions and the charging port. Label every value as an example rather than a fact about a product.

   Checkpoint: A three-view package drawing with H-points, headroom and ground clearance dimensioned.

2. 2

   Explore proportions

   Sketch side views over the package with different cabin positions, roof lines, overhangs and wheel-to-body ratios. Then block out two or three quick 3-D volumes, using subdivision modelling if your Alias version includes it, to see the proportions in perspective. Compare them on screen with the same camera and lighting so the comparison is fair, and pick a direction tied to the package.

   Checkpoint: Two or three proportion studies with a chosen direction and reasons tied to the package.

3. 3

   Set up the reference

   Import the package curves and the chosen sketch as image planes in the side, top and front views at the correct scale. Set the centre plane on XZ and enable symmetry so you only build the left side. Organise layers for reference, curves, primary surfaces and details, and lock the reference layers. Confirm scale by measuring the wheelbase and overall length against the package drawing.

   Checkpoint: References aligned in all views with a measured wheelbase matching the package.

4. 4

   Build the primary curves

   Create the side silhouette, plan outline, beltline, shoulder feature line, roof crown and front and rear sections with low-span CV curves. Keep the curves consistent between views by projecting side and plan curves to make true 3-D lines. Check curvature combs on every curve and rebuild any that show noise. A clean curve network here saves hours of surface repair later.

   Checkpoint: A curve network that reads correctly in all views with clean combs.

5. 5

   Surface the body side

   Build the body side as a few large surfaces bounded by the feature line, beltline and wheel arches, using Rail and Square surfaces. Align boundaries with G1 first and G2 across the feature line where it should be soft. Trim the wheel arches with projected curves and add arch flares if they are part of the design, checking tyre clearance at full steering lock.

   Checkpoint: Zebra stripes on the body side flow smoothly and break only at intended feature lines.

6. 6

   Surface roof, front and rear

   Create the roof and glass as separate surfaces, then the front face with lamp and charging port positions and the rear with tail lamps and tailgate. Use Surface Fillet and Freeform Blend for transitions between the main surfaces. Keep checking the package as you go, especially headroom over the rear occupant and the lamp hard points at the front and rear.

   Checkpoint: A closed exterior with no gaps in shaded mode and headroom above the occupant envelope.

7. 7

   Add key details

   Add shut lines for doors, bonnet and tailgate, lamp graphics, a charging port door, mirrors and wheels as simple representations. Create shut lines by offsetting curves on the surface by a design gap value and trimming, then add short returns. Keep detailing consistent with the chosen design direction, and avoid shut lines crossing the strongest highlights on the body side.

   Checkpoint: Shut lines and details visible in renders without breaking surface quality.

8. 8

   Evaluate and refine

   Review all surfaces with Zebra and curvature shading from several angles. Cut sections at the H-points and wheel centres to check headroom, ground clearance and wheel clearance against the package. Compare the model's proportions against the chosen sketch from the same camera angle, and refine curves wherever the 3-D form has drifted from the sketch's intent. Save each refinement as a new file version.

   Checkpoint: Section views showing package clearance and before-and-after zebra screenshots of refined panels.

9. 9

   Render and review

   Render the car in three-quarter front and rear, side and plan views with a consistent environment and paint material, using VRED, KeyShot or SOLIDWORKS Visualize. Prepare a review board with the package, proportion studies, model, quality checks and renders, labelled as a student concept that does not represent any existing product, and note the next design questions to answer. Keep the scene file so renders can be repeated.

   Checkpoint: A design review board with renders and a short design rationale.

Testing & validation

• Occupant envelopes and package hard points clear the body.
• Zebra stripes flow across boundaries except at intended feature lines.
• Model dimensions match the package within stated tolerances.
• Shaded model has no gaps or overlapping surfaces.

Expected results

A package-based compact EV exterior concept in Alias with a clean surface model, proportion studies, highlight and clearance checks and design review renders.

Take it further

• Run a Flow Simulation of the body to estimate drag and refine the rear.
• Raise selected boundaries to G2 or G3 and compare highlights.
• Create an interior package and dashboard concept.
• Make a 1:10 or 1:18 scale print for a physical review.

Viva and review questions

Learn it at DIYguru

These DIYguru courses and programmes teach what this project needs.