Technical

History

The vehicle named Vera was developed in 2006. Year 2007 was the year of manufacturing and she finally saw daylight in the first half of 2007. Vera has undergone many changes during the years and can now be considered a venerable lady. In her first years she was propelled by the, in the context of eco marathon, very common GX35-engine produced by Honda. The engine was replaced in 2009 with an engine developed in house.

The vehicle was built up around a frame of carbon fiber, supporting all load taking elements. The body was bolted onto this frame. As years passed, the carbon fiber frame became weaker and in 2012 it was replaced by a frame of thin steel alloy tubes.

The vehicle consisted of three parts; two body panels and one load taking frame. The weight of the frame is roughly 8 kg whereas the body weighs close to 1 Kg. The frame was manufactured in thin walled CrMo steel tubes. The body was manufactured in single layer of carbon fiber. The vehicle had two steerable front wheels and one propelling rear wheel. The total weight of the car was roughly 30 kg.

Body and chassis

The current vehicle is made of one honeycomb-reinforced carbon fiber frame that is self-supporting, so no steel frame is needed. The frame/chassis weighs roughly 6 Kg and the car in total weighs about 28 Kg which was the second lightest vehicle at SEM 2015.

Engine

The engine has been developed since 2010 and is currently in its sixth generation. It is a single cylinder 4-stroke, port injected, two valve engine running on gasoline 95 or 98 octane. The first versions of the engine had a large stroke to bore ratio. Later on the stroke was reduced, resulting in a close to square engine. Several investigations have been performed during the years and the result is the generation six of the engine which is currently being developed. All pictures are from engine generation 1.

Engine management system

Since the very beginning of the Vera team a decade ago several different engine management systems was tested and utilized. We have finally developed our own system “Katla”. The ECU was developed as a bachelor thesis project at Chalmers University and is currently running in the car.

Aid systems
To aid the driver during the race two main systems has been developed for the vehicle. The first one is what we call the human machine interface (HMI) and aids to present information to the driver through a display located in the car. This display presents information such as speed, temperatures, lap time, error codes from the ECU etc. There is also a rear viewing camera mounted on the car in order to help the driver to make the best decisions when overtaking and cornering.

Engine specifications

Gen 1 Gen 2 Gen 3 Gen 4 Gen 5 Gen 6
Bore [mm]

29 29 29 39 39  39
Stroke [mm]

70 70 70 70 40  39
Displacement

26,2 cc 26,2 cc 26,2 cc 83,6 cc 47,8 cc  46,6
Exhaust/Intake valve diameter [mm]

12/13 12/13 12/13 12/13 13/13  13/13
Compression ratio

11:1 11:1 11:1 12,7:1 14:1  14:1
Crank shaft

Double sided Double sided Double sided Single sided Single sided  Single sided, reworked
Spark plugs Dual
NGK CM-6
Dual
NGK CM-6
Dual
NGK CM-6
Dual
NGK CM-6
Dual
NGK C2H
 Single
NGK C2H
Injector

Bosch Eco Marathon Honda
Zoomer
Honda
Zoomer
Honda
Zoomer
Honda
Zoomer
 Honda Zoomer/Currawong 16CC
Valve train Single
camshaft/
Dual lobes
Single camshaft/
Dual lobes
Single camshaft/
Dual lobes
Single camshaft/
Dual lobes
Single camshaft/
Dual lobes
 Single camshaft/
Dual lobes
ECU Civinco SA500 Civinco SA500 Civinco SA500 Civinco SA500 Microsquirt  Katla

Gen1 Full Assembly Engine Head Assembly Early Crankshaft Camshaft Exploded Gen1 Engine Head