Fall Validation Demonstration

System Integration Testings:

Total Trials26 (14 Front, 12 Overhead)
Use Case Success22
Success Rate84.62%
Average Time to Finish74s
Table 2. FVD results summary

For the Fall Validation Demonstration, the COBORG system was required to hold and stabilize a representative part while an operator used a drill and screws to attach the part to a forward-facing and overhead wall. The user also detached the board from these walls. Additionally, the user was allowed no more than five minutes for each task.  During FVD, the system successfully attached and detached the panel in both the forward-facing and overhead scenarios; these tasks took the user a little over a minute to complete, well within the allotted five minutes.  A human demonstration was also given for comparison, which took only slightly less time than the COBORG system.  For FVD Encore, the weight of the panels was increased from 3.5 lbs to 7.5 lbs and even 15 lbs.  The 7.5 lb panel was successfully attached and detached in the forward-facing and overhead scenarios.  The 15 lb panel was only tested in the forward-facing configuration for safety considerations.  It was successfully attached to the wall, but some slipping necessitated the user re-aligning the arm during detachment.  More statistics on the system’s success rate can be found in Table 2 above.

Another requirement for the system was that it would support typical usage for at least 20 minutes.  At the end of both FVD and FVD Encore, the total battery life of the system was extrapolated and indicated an entire lifespan of more than 2 hours, well over the required 20 minutes.

The comfort of the system was tested in an informal manner. The system was expected to be worn for 30 consecutive minutes without discomfort. After both FVD and FVD Encore, the user, who had been wearing the backpack for even longer, was asked to report on the device’s comfort.  The user remarked that the device was surprisingly snug and comfortable, with no issues standing out to them.  The user had also been wearing the COBORG backpack for multiple hours consecutively leading up to the demos.

The voice subsystem proved successful by our requirements by the end of spring, so the only changes before FVD were adding final commands and ROS publishers and subscribers for improved interfacing. Because the functionality was the same as the spring, no quantitative tests were used to validate the voice subsystem for FVD or FVD Encore. Instead, the voice subsystem was implicitly tested and validated through successful demonstration of the total integrated use case of the COBORG, with the voice subsystem serving as the control interface for the user to the robot. We tested extreme cases with the voice recognition subsystem during these demonstrations by proving successful functionality in environments with lots of background voices and with loud manufacturing plant background noise during FVD Encore. We faced some challenges during the FVD Encore when our original system microphone became unresponsive as the audience entered the room. Luckily, we had planned for this in risk analysis and had a backup microphone to hot-swap. However, the new microphone was not performing with the same sensitivity and directionality, causing some recognition issues during the demonstration. We also proved voice recognition capabilities during the poster presentation with our original microphone despite the background noise of many other people speaking and asking questions nearby. Through these passive trials, we implicitly validated the success of the voice recognition system integrated in the COBORG.