  Robots have become ubiquitous tools in various industries and households,
highlighting the importance of human-robot interaction (HRI). This has
increased the need for easy and accessible communication between humans and
robots. Recent research has focused on the intersection of virtual assistant
technology, such as Amazon's Alexa, with robots and its effect on HRI. This
paper presents the Virtual Assistant, Human, and Robots in the loop (VAHR)
system, which utilizes bidirectional communication to control multiple robots
through Alexa. VAHR's performance was evaluated through a human-subjects
experiment, comparing objective and subjective metrics of traditional keyboard
and mouse interfaces to VAHR. The results showed that VAHR required 41% less
Robot Attention Demand and ensured 91% more Fan-out time compared to the
standard method. Additionally, VAHR led to a 62.5% improvement in
multi-tasking, highlighting the potential for efficient human-robot interaction
in physically- and mentally-demanding scenarios. However, subjective metrics
revealed a need for human operators to build confidence and trust with this new
method of operation.
