Inertial navigation peripheral/System design


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System schematics


note: Greg fails at typing "inertial"

Software Systems



The PIC device will connect to the laptop via USB and provide position/bearing values when requested. It will perform onboard numeric integration, and return values in meters and percent of circles.

Python "Driver" Class

The driver class for the Locograph will be a Python class called "Locograph". Locograph will handle connecting to the USB device using libusb, meaning a user of this class merely needs to instantiate one and start asking it for values.

Here is something like a UML diagram for Locograph:


A Locograph has the following attributes:

  • position: A tuple of length three - (x, y, z) - expressing coordinate change relative to the laptop in the global Cartesian space.
  • bearing: A number - 0 to 1 - expressing how much of a rotation the laptop has completed in the global Cartesian space.

A Locograph offers the following methods:

  • getPosition(): returns self.position
  • getBearing(): returns self.bearing
  • _updateFromDevice(): polls the USB device for new values.
  • _mapDevice(): sets up the USB device originally.
  • reset(): client asks for coordinate reset.
  • _reset(): ask USB device for coordinate reset.

Python "Game" App

An application using a Locograph can instantiate one, and ask it for values.

Form factor

(insert sketches)

(include sketch model picture)

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