In the early stages of learning a technical skill, trainees require guidance from a mentor through augmented feedback to develop higher expertise. However, the impact of such feedback and the different modalities used to communicate it remain underexplored in immersive virtual environments (IVE). This paper presents a study in which 27 participants were divided into three groups to learn a tool manipulation trajectory in an IVE. Two experimental groups received guidance from an expert using visual and/or haptic augmented feedback, while the control group received no feedback. The results indicate that both experimental groups showed significantly greater improvement in tool trajectory performance than the control group from pre- to post-test, with no significant differences between them. Analysis of their learning curves revealed similar performance improvements in tool trajectory across trials, outperforming the control group. Additionally, the visual-haptic feedback condition was linked to lower task load in three out of six dimensions of the NASA-TLX and a higher perceived interdependence with the expert's actions. These findings suggest that augmented feedback from an expert enhances the learning of tool manipulation skills. Although adding haptic feedback did not lead to better learning outcomes compared to visual feedback alone, it did enhance the overall user experience. These results offer valuable insights for designing IVEs that support mentor-trainee interactions through augmented feedback.

With the mentoring model, a mentee can learn technical skills under the supervision of more experienced peers who demonstrate their knowledge through several communication modalities. Supporting the mentoring model within shared immersive training simulators holds promise in enhancing mentor-mentee interactions and learning outcomes in a safe environment. However, efficient communication within these spaces remains an open issue. This work presents a user study that explores the combination of communication modalities (verbal-visual, verbal-haptic, visual-haptic, and verbal-visual-haptic) to convey instructions to learners on the amplitude of movements to perform during a tool-handling task in an immersive environment. The study aims to examine the impact of the four modality combinations on performance (speed and accuracy of movement replication), mental workload, and participants’ user experience. The results show that participants achieved higher accuracy with the visual-haptic and verbal-visual-haptic conditions. Moreover, they performed the movements faster, and their movement trajectories were closer to the reference trajectories in the visual-haptic condition. Finally, the most preferred verbal-visual-haptic combination enhanced the users’ sense of presence, co-presence, social presence, and learning experience. No impact on the mental workload was observed. These results suggest that combining haptic and visual modalities is the best suited for enhancing learners’ performance. Adding the verbal modality can also improve the user experience in the immersive learning environment. These findings contribute to improving the design of immersive collaborative systems and pave the way for exploring novel avenues of research into the efficacy of multimodal communication for enhancing the mentoring-based acquisition of technical skills in VR. These tools hold promise for diverse applications, including medical simulation.