This week I worked on both localization and mapping. More specifically, I ordered more materials for the anchors, such as Li-Po batteries as well as a Li-Po battery charger. I worked with Weelie to develop a debugging program that would take in the positions of anchors and use those as well as an incoming serial stream of the distances to the anchors to estimate the position of the tag. However, the current localization scheme is slow to update (around 2Hz), and rather inaccurate (fluctuates about an area larger than 1m^2). To remedy this, I am currently working on a gradient descent-based method of solving for the user’s position that I hope will be more robust. I also got started on mapping software for floor plans, that allows me to mark what areas of a floor are walkable space and what areas are not (such as walls, rooms, etc). When completed, this will plug into the A* algorithm to route the user around places they cannot traverse.
As with regards to the schedule, I am currently still on track. This next week is supposed to be the week where I finish the tag device by adding and programming the accelerometer. It is also the week I am supposed to map out at least a single hallway for tracking with the system.
In this coming week, I hope to program the accelerometer (something I have written the code for but have not yet wired up), assemble the finished tag device, test out the new localization method, and map out a hallway. To assist in this mapping effort, I also ordered a tape measure which also functions as a laser ranging device, which is arriving in this coming week.