Hello, Automo

I've decided to refer to my RC-to-autonomous truck project as Automo. There's no more particular motive for choosing this name than it sounds similar to "autonomous" and "automobile", both of which are relevant for this project. It's interesting to note that the character string "automo" is the matching substring for the words "autonomous" and "automobile", but this is coincidental in that it played no role in my choosing (I realized in while writing this update)!

I've been experimenting with various H-bridge and control logic circuit designs for the main driving motor, but haven't yet come up with one that is optimal. I haven't had time enough in the past few weeks to further develop the H-bridge circuit design due to school and work obligations, and haven't gotten anything tested on the truck.

Aside from tinkering with various circuits, I've written a simple application (using Visual Basic .NET with GDI+) that simulates the ultrasonic sensor and servo configuration I plan to use for basic environment map generation and navigation. A few screen captures of the program follow are shown below:

The "compete" program window:


The map of the physical world and the player and sensed distances:


The program generates a simple 2D physical world, places a "player" point (representing Automo) in the world, and then draws lines corresponding to the read distances taken by the ultrasonic sensor at a specified read frequency. In the shown screen captures, the read frequency is set to 12 reads/revolution, so readings are taken every 30 degrees. The ultrasonic sensor that I'm using for Automo has a maximum range of approximately 3 meters. I'm modeling this in the program such that if no distance is measured less than the maximum distance, the entire green line is drawn.

Before moving onto adding more features to the program, I'm going to clean up and organize the code code a bit, in order to make it easier to work with. After this brief janitorial intermission, I'll likely instate a consistent pixels-to-meters scale, better organize the ultrasonic distance readings, and add automated navigation based on this data. I also plan to add a simulated infrared sensor that sweeps 180 degrees back-and-forth (continuously) on the front of the player. The infrared sensor data might be used for more immediate navigation decisions, while the longer-range ultrasonic data might be used for things like planning ahead or guessing which general direction to move.

Expect a nice post regarding Automo's front steering circuit and associated AVR-C control code relatively soon (and maybe some other random information).