15-01-2013, 04:13 PM
Construction of ecocars and windturbine cars following
the CDIO principle
Construction of ecocars and windturbine cars.pdf (Size: 174.15 KB / Downloads: 30)
Abstract
This paper describes the process of active learning in connection with the construction of
concept cars by the students at the Technical University of Denmark (DTU). The concept of
the ecocars is to develop a car where the top priority is energy efficient solutions in order to
make the car run as far as possible on one litre of gasoline energy equivalent. In parallel the
idea of the wind turbine cars is to design-build vehicles for driving directly against the wind,
powered by a wind turbine. The projects are applied in an elective course for bachelor
students with approximately 2 years of experience. However, students are also associated
from other student activities like bachelor and master projects. In order to carry over knowhow
from previous years, which is essential to the success of the whole process, some
“older” students are encouraged to participate in the activities for more than one year. This
also gives the students a possibility to evaluate new ideas that was generated during testing
and operation of the developed cars.
The projects is carried out over 2 semesters (1 year) for the ecocar and semester for the
wind turbine car giving a basis for a detailed comparison between two projects containing
similar teaching elements although with different origin. Both projects contains all 4 elements
of the CDIO1 principle in one teaching project, i.e. conceiving the engineering elements of the
cars, the design-build phase and finalizing at internationally organized races with the cars.
The project has been running repeatedly for 6 years and has been implemented more and
more smoothly in the teaching program at DTU. The organization of the projects is a very
essential task for a successful outcome and a very important learning process in itself.
Experiences from the projects will be compared and described in details in the paper
focusing on the development and evaluation of the teaching and active learning processes
observed over the years.
Introduction
Future engineers are expected to work in a very dynamic environment where facts will
change, be questioned and discussed. The education of engineers will therefore have to
change according to these trends and focus more on the necessary competences in this
environment. More specific communication and collaboration are strongly needed skills.
Traditional teaching in engineering has been organized primarily as one-way communication,
where the students are mainly passively following the teacher’s speech. This is indeed very
sensible and applicable for basic courses in mathematics, physics etc. with many students.
In this type of courses predefined exercises or problem solving in smaller groups is typically
an additional option for the students. Finally, assessment has usually been based on a
written exam. These type of courses are, however, rather uninspiring for late years students
and do not appeal at all to many students. Education in fairly narrow fields as in typical
courses trains skill towards analysis aspects of problems rather than synthesis, which real
engineering typically is about (Gustafsson2). Using CDIO in design-build projects opens to
multi disciplinary aspect engineering, however, a good setup for a design-build project has to
be well prepared since it does require a large number of factors to be taken into account
which traditional courses generally not include (Malmqvist et al.3). In the Internal Combustion
Engine Group (ICEG) we have implemented CDIO4 course activities in order to address the
above mentioned remarks.
In the following the two CDIO activities are described individually. Later on the experiences
from the activities are compared and evaluated.
2. Ecocars
The course is running over 2 semesters (1 year). The activities contain all 4 elements of the
CDIO principle in one teaching project, i.e. conceiving the engineering elements of the cars,
the design-build phase and finalizing at internationally organized races with the cars. The
project has been running repeatedly for 6 years and has been implemented more and more
smoothly in the teaching programme at DTU. The organization of the projects is a very
essential task for a successful outcome and a very important learning process in itself.
The general course objectives are: To let the students work on practical construction tasks,
based on theory. The idea is to construct a fuel economic vehicle. This vehicle should be
able to participate in an international university competition like "The Shell Eco-Marathon".
The learning objectives of the course are defined as:
A student who has met the objectives of the course will be able to:
Work creatively with a given problem
Design a functional solution based on a theoretical idea
Carry out an overall energy evaluation of a vehicle
Carry out an analysis of the existing knowledge about a certain topic
Apply engineering measurement principles as an assisting tool.
Put up a working plan for the practical carrying-out of an engineering problem
Work responsible in a team
Write a technical report
CDIO activities
In the following text the different elements of the CDIO principle is described in relation to the
activities. An overview of typical overall process elements is given in Table
Conceive
The basic idea is to have an inspiring goal to work towards. Therefore, a car is chosen as the
goal, since this is a product we can all relate to in our daily life. This is predefined from the
start and cannot be influenced by the students. Some basic ideas about the concept, in order
to improve the performance of the car are retrieved from experiences the previous year and
cannot either be influenced by the “new” students. These ideas are, however, a product of
the overall learning process that the “old” student have undergone and carries over to the
new team. With these predefinitions of the product the students start to conceive their own
ideas which are discussed and evaluated before the next step.
Design
Based on the ideas generated, the project is organized in smaller groups where the students
are discussing the design of the individual parts of the car. This process is followed by
production of, f. ex., drawings for a certain part of the car. It could also be setting up
specifications for a calculation tool, needed for simulation of the energy consumption for the
vehicle at variable conditions.
Implementation
After receiving the vehicle part from the workshop the students are supposed to build the
vehicles from the individual parts, which could be engine, frame, wheels, carbon fiber body,
electronic control system etc. This requires strict collaboration between the individual groups
and an early agreement on the time schedule (Gantt Schedule) for the whole project. The
individual components and part systems, like the drive train, are tested before integration in
the vehicle.
Operate
After assembling of the car the product is tested, in the end at an international fuel economy
race (Shell Eco Marathon).
The students
The “team” consists of students with skills from all over the university. The most represented
expertise comes from the mechanical engineering department, the electronic engineering
department and the design engineering department.