## 6 Discussion
### Soft Robots Capable of Whole-Body Manipulation Convey the Idea of Safety and Human-Likeness  
One of the major limitations of how robot manipulation has been done in the past and even now with most bi-manual robot systems is that objects are manipulated using end-effectors. For example, humanoid robots in factories pick up medium-sized boxes between their 2 palms and hold the payload away from their body [77]. Humans use mechanical advantage and instead use their arms and chest in combination to grasp large, bulky, or unwieldy objects; this is called _whole-body manipulation_. A layer of softness further creates compliance so that the robot can securely hold onto an object [78].  
Whole-body manipulation is an inherent concept for TRIbot and Dex (from DUO); the _mod assist_ sit-to-stand maneuvers are based on best practices used by Occupational and Physical Therapists which leverage their whole bodies (see EI-8\({}_{US}\) in [13]). Because the robot contacts the Older Adult (OA) using its hands (open palms), its upper and lower arms, and its shoulders to have multiple contact areas, one of the biggest concerns participants had was whether the robot would be soft enough. Participants' concerns surrounding density are often related to safety concerns, similar to previous research [79]. Shown in Figures 7 and 9, the orange areas on the robots represented soft/padded/cushioned areas that the user would intentionally have high contact. Participants' safety concerns surround issues of falling or bumping into the robot. Thus, these soft areas could decrease the chance of impact injury, while also providing comfort to users when touching the robot in the cushioned zones. Using materials that are \"similar to soft biological materials\" can reduce the potential injury that can occur for users when using assistive robots [80].  
While general softness abated safety concerns, participants did not want the robot to be \"too soft\" as this was viewed as making the robot weak and unable to provide secure support. Participants expressed the need for a firm frame to absorb impact and provide secure support (see Section 5.1.3). Human-like robots with soft and gentle embrace can provide support that decreases users' concerns regarding safety and comfort [81]. 17 participants requested that the robot be soft on areas that touch them, but have a firm structure underneath the softness, often comparing this to human bodies with skin and bones (see Section 5.1.3); this analogy is consistent with prior research [79].  
Finally, the temperature is another aspect that participants requested to be comparable to human-likeness (\(n\) = 21) or having warmth (\(n\) = 16). Prior research shows that users prefer soft and warm physical interactions with robots [81]. A soft and warm robot capable of whole-body manipulation could provide comfortable functional physical assistance, such as helping an OA to sit up in bed first thing in the morning or get dressed. Beyond functional caregiving tasks, such a robot could also provide the sympathetic touch and hug [81], which could, in turn, help to foster a social relationship between an OA and a caregiving robot [82].