This past week I worked on 1) debugging the HLS version of RRT, 2) system integration, mainly the communication between the Ultra96 and the laptop, and 3) the final presentation slides.
I was able to compile using HLS last week, but the tree that RRT generated at first glance seemed right but instead had some errors. Namely, RRT seemed to converge towards a configuration of the state space that wasn’t even a valid RRT tree that could be used for a motion plan. After K iterations of RRT in an empty state space (no obstacles), I saw two subtrees being grown from the initial start and end points, but the two subtrees did not connect. For some reason, further RRT iterations past K did not result in changes to the tree. I suspect the reason for this error is due to one of two possible causes—either I made an error when refactoring the code from being modular with many functions into one main function, or I made an error when altering the code to work in hardware (e.g. replacing uses of the C rand() function with a LFSR for random numbers. I discussed this problem with Chris, and we plan on meeting tomorrow to debug further.
While the UART library I found last week worked for transferring small number of bytes, I was not able to transfer the RRT data without losing info. I was not able to find a solution, and thus decided to move away from using UART and swapped to a more reliable but slower method of transferring the data: by sending the file over the network via scp.