So I have come to the conclusion that a car may be too big a project for my first attempt at electrical engineering.  So I am taking a step back.  I am going to try and retrofit a gas riding lawnmower with an electric motor.

This is a project I may actually be able to make progress on.  You see, I can buy a cheep, used riding lawnmower for $150 (especially since “runs” isn’t one of my primary concerns).  Then I only need to find a motor, controller and battery pack and get to work.  Also, because I only have half an acre of land…I won’t need a large number of batteries (though I will try to figure out how many batteries I need before finalizing my design).

So, here are my goals and mission statement for this project

Mission Statement: Build an operational electric riding lawn mower.

Goals:

1. The mower must be able to cut my grass on a single charge.
2. The mower must be rechargeable in one week
3. When overloaded (if the blades get stuck), the mower must not cause harm to the operator or anyone nearby
4. When overloaded, the mower must operate again when the overload is cleared without needing to replace parts.

That pretty much covers it.  Seems simple…now where do I start?

This is something else I like to do with my projects.  Much broader than system requirements, but more specific than the mission statement.  These goals also tend to me “Nice to haves”.  Their importance and relative complexity will determine if they make it in to the final product.

1. Travel 60 miles at 70 mph on a single charge
2. Charge in less than 8 hours using a specially designed charger
3. Charge in less than 16 hours using a standard 110 volt AC plug
4. Cost less than $6,500
5. Have an operational air conditioner that will still allow for travel for 45 miles at 70 mph
6. Do the entire project in metric (exception: miles will be used where necessary instead of kilometers)
7. Power Steering
8. Power Windows
9. Utilize Recouprative Braking
10. Display the relative power remaining on the dash
11. Display the distance that can be traveled at the current speed on the dash in miles

The nice thing about project goals is that I can add to them as necessary.  This will do for a start.

I like to start all of my projects with a mission statement.  This helps to focus my efforts.  By specifying what I am trying to accomplish, it helps to prevent my own tendency to add to the project because “it will be cool”.  So, with no further ado:

Retrofit a Honda Prelude to operate off of portable electric power for daily commuting to and from work.