## 4 Conclusions  
In the context of the rehabilitation of the upper limbs of patients affected by spinal cord injury, VR technologies facilitate the performance of the necessary movement repetitions. By means of devices such as Leap Motion, it is possible to work on the motor aspects of the upper limbs, enabling tasks such as reaching, grasping, manipulating, and transporting virtual objects by executing certain hand movements and gestures. However, in those cases there is no sensitive information about the objects being manipulated. Therefore, VR needs to be coordinated with robotics devices. Unfortunately, these technologies are often expensive and cumbersome. Some devices are uncomfortable to wear, and some rehabilitation platforms do not provide any feedback to the affected limb. This often leads to an abandonment of rehabilitation platforms. For these reasons, they are not suitable for domestic use, which would allow the amount of therapy results to be increased further. On the contrary, the work presented in this manuscript took advantage of low-cost VR systems and a custom-made haptic device to enhance the involvement and engagement of patients, provide a congruent afferent feedback during motor exercises, and benefit from the flexibility of virtual scenarios. Since this research was carried out in patients with cervical spinal cord injury, it is of special interest to integrating sensory functions because they are altered and/or modified after injury. In this way, through the haptic feedback delivered by the thimble developed in this manuscript together with the use of Leap Motion, the therapeutic objective in neurological patients is enriched. It is not possible to generate detailed sensory information about the size and texture of the virtual object but it is possible to recreate the sensation of holding an object in the hand. From a rehabilitation point of view, this is crucial for patients with neurological diseases. Three games were designed and implemented for SCI patients, meeting the needed requirements for adequate rehabilitation. The user can interact with the games just by using their hand, thus focusing only on moving the arm and the hand in the correct way. To achieve this, the platform takes advantage of the Leap Motion device to represent the hand movements and access the data relative to the positions and velocity of the user's index fingertip. The platform was developed to provide the user with the ability to receive haptic feedback that allows them to be more aware of the interaction with the virtual environment. The work also focused on the development of an easily wearable device that can provide two different types of tactile feedback: vibration and pressure. Vibration was chosen because of its significant effect in neurorehabilitation. Several previous studies reported improvements in movements and a reduction in spasticity [36]. Pressure was selected as a direct association regarding the distance to the correct path and to feel the hardness of the materials [34]. The design and implementation of the mechanical parts, the connections, and the control were oriented to allow the patient to interact with the virtual environment without interfering with performance. A proof of concept to check the functionality of the platform with both SCI patients and healthy subjects was conducted. The results obtained in terms of movement, error, and time showed some small differences between the groups. A statistical analysis with a larger sample must be carried out to clinically validate the system and to obtain statistical conclusions related to the degree of motor impairment in SCI patients. Nonetheless, the proof of concept provided glimpses into some benefits of the system, which are exposed hereafter:  
* All the devices used to build the platform are low-cost and easily adaptable for different people, with a short preparation for the session. * The configuration options used in this project allows different virtual scenarios and training situations personalized for different patients to be created.