## 2 Material and Methods
### VR Application
A recent state-of-the art review of devices for performing physical therapy at home or assisting with ADLs identified at least 15 systems that employ VR feedback, and in most of these cases, wrist support (ROM assessment), and in a few cases grip function, was considered [42]. No further information on finger movements is given. Therefore, the definition of the virtual scenarios and the placement of the interactive virtual objects were done in such a way so the user must reach a certain ROM for each joint to actually perform the tasks. All six virtual scenarios are depicted in Figure 2.  
By applying inverse kinematics to the controllers' positional and rotational data, the ROMs in the sagittal and horizontal planes of these body joints were evaluated. Tables 1-6 detail the sequence of actions to be performed in each activity, the movements of the upper limb, and the ROMs involved for each joint. Each activity is further described in detail. _Hand-washing activity:_ In this task, the user must follow the instructions shown in the mirror, step by step, to complete the action of washing their hands. The user is located in front of the toilet cabin and must move to stand in front of the sink, whose tap can be opened and closed by interacting with the yellow and blue buttons. Small shelves are placed to the left and right of the tap. On top of those shelves there are objects that must be reached: gloves and soap (see Figure 2A). The height and distance of these shelves and \begin{table}
\begin{tabular}{c c c} \hline \hline
**Action** & **Upper Limb Movement** & **Target ROM** \\ \hline \multirow{5}{*}{Turn on/off the faucet} & Shoulder flexion & 90\({}^{\circ}\) \\ \cline{2-3}  & Elbow extension & 0\({}^{\circ}\) \\ \cline{2-3}  & Elbow pronation & 70\({}^{\circ}\) \\ \cline{2-3}  & Wrist flexion & 45\({}^{\circ}\) \\ \hline \multirow{5}{*}{Placing hands under water} & Shoulder flexion & 45\({}^{\circ}\) \\ \cline{2-3}  & Elbow flexion & 90\({}^{\circ}\) \\ \cline{2-3}  & Elbow neutral position & 0\({}^{\circ}\) \\ \cline{2-3}  & Wrist neutral position & 0\({}^{\circ}\) \\ \cline{2-3}  & elbow flexion & 45\({}^{\circ}\) \\ \cline{2-3}  & Wrist radial-ulnar rotation & 15\({}^{\circ}\) \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Sequence of actions and the upper limb movements involved in the hand-washing activity. Figure 2: Virtual environments for the activities. (**A**) The cabin area for the hand-washing activity, consisting of a faucet, a mirror, and the interactive objects: gloves and soap. (**B**) The barn dinning area for the pouring a drink activity. (**C**) The interactive keyboard for the playing the piano activity. (**D**) The toilet cabin area for the animal caring activity. (**E**) The forest area for the picking apples from trees activity. (**F**) The orchard field area for the picking vegetables up off the ground activity. the buttons on the faucet are configured according to user's position to ensure the proper shoulder extension, elbow movements, and wrist rotations (see Table 1). _Pouring a drink activity:_ In this task, the user must follow the instructions shown on the board, step by step, to complete the actions of pouring water into a glass and drinking from it. Initially, the user is placed in front of the bar where the interactive objects (bottle, glass and wooden board) are placed (see Figure 2B). They are arranged at a comfortable height and a distance appropriate to perform the flexion movements at the elbow, shoulder, and wrist to reach the objects; and elbow pronation and wrist movements to grab the objects (see Table 2). _Playing the piano activity:_ In this task, the user stands in front of the piano keyboard. The height of the piano is set to allow the subject to perform the elbow, shoulder, and slight wrist flexing movements (see Figure 2C). To complete the activity, the user must follow the melody for 2 min. This involves pressing the keys shown on the score panel (see Table 3).