EV management system

We started by building an electric car and quickly we wanted to be masters of the entire system, knowing exactly what is going on under the hood.

Where is the power going, and how much? How warm are things getting? How fast are things turning? What is the hydraulic pressure inside our automatic transmission? Answering these questions will allow us to design the most efficient and refined EV Management System possible (and we are less likely to break anything.)

We set out to create the best EV Management System we could come up with. We wanted to build great electric cars, and share our knowledge, progress and products with others.

Overview

In order to make the system as versatile and universal as possible, we rely on software to handle the data. Software can easily manipulate, calibrate, display, record and analyze EV metrics. Before we can do this, however, we have to get the information into the computer. We decided to use USB as the communication method and our OpenAPI packet structure as the language.

Next, we need to accurately measure things in our Electric car. This is what our AutoBlocks do. Each AutoBlock is designed to gather specific pieces of information such as RPM (AutoBlock RPM) and Amperage (AutoBlock AMP), and communicate that to your central computer.

Basic setup

We designed our products to function alone or in a group for more advanced metering. Below you will see a basic setup where 2 of our AutoBlocks are used to measure Current and Motor RPM. Current is measured by the AutoBlock AMP by measuring the magnetic field around a cable using a Hall-effect sensor. Motor RPM is measured by the AutoBlock RPM by measuring the time between pulses (Period) from various pickup sensors and knowing the number of pulses occur in one revolution.

Creating 'Hybrid sensors'

The beauty of this system is revealed once the computer receives these raw values from sensors - in this example: Instantaneous Amperage and Period. Once the computer has these values, it becomes much easier to manipulate the data.

As a result, we can create our own formulas (using constant, known values, and measured variables) to display the exact type of information we are looking for.

For example:

  • Instantaneous EV efficiency: kW•h/mile
  • Average EV efficiency: kW•h/mile avg
  • Optimum motor RPM at various vehicle speeds
  • Best gear to drive in
  • many, many more! (probably)

    • Instrumentation

    Once your EV data is in a common format and available at one place, you can do whatever you want with it. How do you want your EV to tell you its feelings?

    • Should it be with a big colorful LCD with virtual meter or a simple 2-line graphical display?
    • Or how about a hand-held smart phone or one of those Netbooks?
    • What about a single-board computer hidden away somewhere moving some analog gauges and recording the data?
    • Maybe one of those Arduino Microcontrollers you've heard so much about?

    We don't care - do whatever you want.

    By using some sort of computer to drive actual physical gauges, one can retain the simple, immediate driver feedback with more advanced features such as saving your EV data for later analysis.

    All of these things (and probably more) are possible, and only limited by software. We encourage you to improve upon what we have done, as long as you share it with everyone.

    Stay tuned for more information and examples of how our AutoBlocks and the OpenAPI EV Management System is used.

    Let us know what you think via our Contact Page