We are officially starting the open source project for the realization of the universal conversion kit of a traditional car in an electric vehicle. Several weeks have past since we have launched our website and finally I am posting the first part of the project.
As anticipated in my May 17, 2014 post, iaiaGi is based on designed guidelines described in Seth Leitman and Bob Brandt’s book (Build your Own Electric Vehicle – Third Edition). I have spent the past weeks to study, translate and adapt the entire process of mechanical dimensioning of the chosen car to electric. I have in fact based my choices on the following considerations:
- The iaiaGi project aims to reduce production costs of an electric car. For this to be possible, I have chosen to convert the car instead of projecting an entire new electric vehicle. I have also chosen to release the present project from patents, in order to permit everyone to offer their contribution with ideas, improvements and optimizations.
- Lower costs means also the possibility to contact a market of potential buyers who are interested in moving towards a zero emission vehicle, without having to take out a bank loan. In this way, the project will be directed initially to treat the conversion of subcompact and compact cars. The codenames for the conversion kit will be Kevin for the subcompact cars and Roxanne for the compact cars.
- The first document of the project will cover Kevin, so subcompact cars. As reference I have chosen the Renault Modus 1.5 dCi 2004 that my wife and I drive daily. This vehicle will help me with the construction of the first prototype using the kit (my wife has authorized me to disassemble her car).
This said, let’s begin a rough description of mechanical dimensioning of that part of the project regarding iaiaGi Kevin. You will find part 1.0 of the document here. Inside the iaiaGi repository on GitHub, in addition to the Read me and License files, you will find the folder Projects; inside this folder you will find another folder named Kevin that contains an Excel spreadsheet named “iaiagi_prj_kevin_v1.0_20140702.xlsx”.
The Excel file is basically a design tool divided into sheets. Each sheet contains information about a particular aspect of the mechanical design process of the kit:
- Equations: This table contains all the physics formulas used to design the kit along with dimensional analysis of each of them.
- Constants: List of physical constants.
- Measurement Units: Table for converting units of measurement from the American system to the International System and vice versa.
- Acceleration Force: normalized tables for the estimation of the forces in play during the acceleration phase relatively to the gear ratio used.
- Hill-Climbing Force: normalized tables for the estimation of the forces in play in relation to the slope of the terrain.
- Ev Conv. Weights Compared: example of weight distribution before and after the conversion to electric for a vehicle weight of 3000 lb (in this example the information is related to the American Ford Ranger pickup).
- Coefficient of Drag: tables and graphs for the estimation of various types of resistance to which is normally subject a land motor vehicle.
- Drivetrain Efficiencies: example values relating to transmission ratios (always referred to the American Ford Ranger pickup).
- Torque Required US and Torque Required IS: spreadsheets for estimating the values of force and torque needed to move the Renault Modus 1.5 dCi used as a reference vehicle of the subcompact Kevin car (obviously US stands for the American system of measurement units, while the IS system stands for the International System of measurement units).
As you can easily verify I translated from English into Italian all the concepts and information contained in the Excel spreadsheet. All this work will bring us enormous benefits in the future in interacting with those who are on the other side of the world.
I will stop here for now and invite you to check the next post which will contain more details about the project.