# A Prototype Mechatronic Device for Upper Limb Rehabilitation and Analysis of Its Functionality
## 2 Motivation and Contribution  
The design of rehabilitation devices necessitates a thorough anatomical analysis of the targeted body segment, along with an assessment of motor capabilities in patients with specific impairments, such as limb paresis [34; 32; 35; 36; 37; 38; 39; 40; 41; 42; 43; 44; 45; 46; 47; 48; 49; 50; 51; 52; 53; 54; 55; 56]. Typically, a prototype is developed to verify the underlying design assumptions. During the design process--which extends into the construction phase--the development of both conceptual and prototype solutions is essential. A significant proportion of existing devices incorporate highly complex mechatronic systems [34; 32; 35; 36; 37; 38; 39; 40; 41; 42; 43; 44; 45; 46; 47; 48; 49; 50; 51; 52; 53; 54; 55; 56]. They are intended for function-specific evaluation, depending on the area of impairment, as well as for the ongoing monitoring of selected motor functions throughout the rehabilitation process [56; 57; 58; 59; 60]. Consequently, their high cost constitutes a primary barrier to widespread adoption. A review of current solutions reveals a lack of simple mechatronic devices on the market based on the Box and Block Test methodology, which could support active rehabilitation exercises [61; 62; 63; 64; 65; 66; 67; 68; 69; 70; 71]. A portable upper limb rehabilitation device is described in an American patent publication [61]. This device features a forearm support mounted on a movable base, enabling the monitoring of both limb movement and forearm pressure exerted on the support surface. The forearm attachment facilitates guided motion during exercises, thereby preventing uncontrolled and improper limb movements. Another relevant system within the scope of this study is the Bimeo PRO, designed specifically for upper limb rehabilitation, with a focus on enhancing hand motor function [62]. The system comprises a split spherical structure and two electronic measurement modules, which are affixed via straps to the wrist and elbow, along with a base on which the entire sphere or its halves may be mounted. Rehabilitation exercises are modelled on daily hand activities, with task instructions presented on a monitor to guide the process. A further mechatronic rehabilitation device for individuals with hand dysfunction is the Pablo system [63]. It includes a universal mechatronic shaft and a set of passive auxiliary external components into which the shaft can be inserted. This shaft is used for assessing and training finger and arm movements, measuring grip strength and range of motion, and providing audiovisual feedback via a monitor. An additional passive module combined with the shaft enables wrist and elbow training through exercises performed using a ball that supports the open hand. Tyromotion Myro [64] is another notable rehabilitation device for upper limb therapy, especially hand rehabilitation. It incorporates a touchscreen panel that enables virtual reality-based exercises. The adjustable screen allows task-based rehabilitation involving real objects--such as a pen--thereby enhancing user engagement. A similar approach is employed in a device developed at the University of Alberta, known as The Air Touch System [65]. This system enables users to complete rehabilitation tasks displayed on a touchscreen integrated into a tabletop. Exercises are performed by moving fingers across the display, creating an intuitive and interactive training environment. In the context of upper limb rehabilitation and assessment--particularly of hand function--virtual reality (VR) systems based on the Box and Block Test (BBT) and the Fugl-Meyer Assessment scale (FMA) have also been investigated. Several studies have examined the effectiveness of simplified rehabilitation devices such as Neuro-X(r) [66]. These systems rely on videographic communication and require participants to perform specific tasks, such as maintaining the balance of a virtual object on screen, responding exclusively with hand movements. Similarly, [PERSON] et al.