Search Results (28)

This research addresses the enhancement of operational efficiency in apple-picking robots through the design of a bimanual spatial configuration enabling obstacle avoidance in contemporary orchard environments. A parallel coordinated harvesting paradigm for dual-arm systems was introduced, leading to the construction and validation of a six-degree-of-freedom bimanual apple-harvesting robot. Leveraging the kinematic architecture of the AUBO-i5 manipulator, three spatial layout configurations for dual-arm systems were evaluated, culminating in the adoption of a “workspace-overlapping Type B” arrangement. A functional prototype of the bimanual apple-harvesting system was subsequently fabricated. The study further involved developing control architectures for two end-effector types: a compliant gripper and a vacuum-based suction mechanism, with corresponding operational protocols established. A networked communication framework for parallel arm coordination was implemented via Ethernet switching technology, enabling both independent and synchronized bimanual operation. Additionally, an intersystem communication protocol was formulated to integrate the robotic vision system with the dual-arm control architecture, establishing a modular parallel execution model between visual perception and motion control modules. A coordinated bimanual harvesting strategy was formulated, incorporating real-time trajectory and pose monitoring of the manipulators. Kinematic simulations were executed to validate the feasibility of this strategy. Field evaluations in modern Red Fuji apple orchards assessed multidimensional harvesting performance, revealing 85.6% and 80% success rates for the suction and gripper-based arms, respectively. Single-fruit retrieval averaged 7.5 s per arm, yielding an overall system efficiency of 3.75 s per fruit. These findings advance the technological foundation for intelligent apple-harvesting systems, offering methodologies for the evolution of precision agronomic automation. Full article

Ensuring mathematics education for all learners, including students with blindness learning in mainstream classrooms, is crucial. This exploratory research aims to clarify the characteristics of geometric learning among students with blindness and to identify the factors contributing to the challenges faced by this population. The Van Hiele theory of geometric thought served as a reference framework. Qualitative data were gathered through group interviews with specialists in the field of education for students with blindness and analyzed using inductive analysis. Participants affirmed that students with blindness progress through Van Hiele levels of geometric thought in a manner similar to sighted students, suggesting that much of the learning can take place alongside sighted peers in mainstream classrooms. However, they also highlighted the unique challenges these students face in reaching level 0, a level where students recognize shapes without a formal understanding of their properties or attributes. Among the reasons for these challenges were that for these particular students, subskills, such as bimanual exploration, hand coordination, and cognitive integration, are required to reach level 0. The study also identified the necessity for specialists in visual impairment education to guide students using appropriate tasks and learning materials that reflect the characteristics of haptic perception. Since level 0 serves as a gateway to both basic and advanced geometry, the findings underscore the importance of providing differentiated support that targets these subskills early in students’ schooling. To ensure meaningful geometry instruction, mainstream teachers are encouraged to collaborate with specialists in visual impairment education, who can guide the selection of appropriate learning tools and support the development of the subskills. Full article

Background/Objectives: The steady increase in the global older adult population highlights critical challenges, including the development of preventive strategies to extend healthy life expectancy and support independence in activities of daily living. Although there is an aging-related reduction in manual dexterity, the difference in bimanual coordination performance between young and older adults remains unclear. We aimed to elucidate the characteristics of bimanual coordination among young, young-old, and old-old adult participants. Methods: The participants performed in-phase (tapping the thumb and index finger together as fast as possible) and anti-phase (alternating movement between the left and right fingers) bimanual coordination tasks, and intergroup comparison of the task parameters was performed. The receiver operating characteristic curve was also conducted to calculate age cut-off points for bimanual coordination. Results: The number and frequency of taps significantly decreased sequentially in young, young-old, and old-old adults, whereas the average of tap interval significantly increased in this order (p < 0.05). There was no significant difference between the young-old and old-old groups in the average local maximum distance (p > 0.05). These findings indicate that bimanual coordination task performance varies depending on specific parameters. Furthermore, the age cut-off points for bimanual coordination were determined as 68.5 years for the right-hand number of taps (AUC = 0.73) in the anti-phase task, 73.5 years for the right-hand average of tapping interval (AUC = 0.72) in the anti-phase task, and 65.5 years for the left-hand frequency of taps (AUC = 0.72) of the anti-phase task. Conclusions: the number of taps, average of tapping interval, and frequency of taps are potential indicators of aging-related changes in bimanual coordination. Full article

Grasping others’ intentions from their actions is essential for learning, as it enhances the ability to identify collaborative acts and anticipate others’ actions, facilitating effective coordination toward shared goals. From a young age, children seem to recognize when others are working together based on their interactions and use this understanding to inform their own learning. Although much of early learning occurs in joint contexts, little attention has been devoted to understanding how children learn by participating in joint actions and by observing others acting together. Using a puzzle box paradigm, we tested 3–6-year-old children’s imitation of an inefficient performance following individual and joint demonstrations in which the inefficient performance did or did not involve bimanual or joint coordination. This allowed us to test whether the tendency to overimitate extends to joint actions and how action coordination modulates imitative behavior. We found that overimitation extends to joint actions, as indicated by similar rates of inefficient copying following individual and joint action demonstrations. Furthermore, our results suggest that action coordination did not play a significant role in modulating children’s tendency to overimitate. Taken together, the results of the study advance our understanding of how learning occurs in social interactions. Full article

Individuals with hemiparetic cerebral palsy (CP) exhibit reduced use of their more affected (MA) arm, yet the factors that influence its use during activities of daily living remain elusive. The objectives of this study were to describe the relative use of the MA arm during an ecological task, examine its relationship with the level of impairment, and investigate its association with performance in various unilateral and bilateral tasks. Methods: Participants took part in two sessions comprising robotic assessments and clinical assessments of motor functions, as well as accelerometry measurement during kitchen tasks. Four variables were derived from accelerometry data. Stepwise regression analyses were used to identify the best contributors to the accelerometry variables among robotic and clinical assessments. Results: Nineteen adults with CP (34.3 years old ± 11.5; MACS I = 7, II = 6, III = 6) were included. The Use Ratio measured during the kitchen tasks ranged between 0.10 and 0.63. The best predictors of all accelerometry metrics were two bilateral assessments (r² = 0.23–0.64). Conclusions: The importance of assessing bilateral tasks was reaffirmed by the key role played by two bilateral tasks in determining the relative use of the MA arm. The results support the use of intensity-based accelerometry metrics to measure MA arm use. Full article

Background/Objectives: This quasi-experimental study examined the effectiveness of an intensive, group-based pediatric constraint-induced movement therapy (pCIMT) program for young children. Methods: Thirty-five children aged 21 months to 6 years, with unilateral hemiparesis (HP), or weakness on one side of the body from varying etiologies, participated in a 4-week intensive, interprofessional, theme- and group-based pCIMT clinic program in the Midwest, United States. The program ran for 4 weeks with 3 h of therapy per day, 5 days per week with 3 weeks of 24 h casting for the unaffected arm, followed by 1 week of bimanual focus. Outcome measures included the Quality Upper Extremity Skills Test (QUEST), Assisting Hand Assessment (AHA), Canadian Occupational Performance Measure (COPM), and Pediatric Evaluation of Disability Inventory (PEDI). Results: The participants statistically significantly improved the unilateral function of the HP arm in four of five QUEST variables (p < 0.009), bimanual coordination as measured by the AHA (p < 0.001), and some areas of occupational performance as measured by the COPM (p < 0.001) and PEDI (p < 0.05). Conclusions: This study revealed the intensive, group-based pCIMT clinic model was effective and feasible to implement with the support from various stakeholders. Full article

Complex motor skills can be acquired while observing a model without physical practice. Transcranial direct-current stimulation (tDCS) applied to the primary motor cortex (M1) also facilitates motor learning. However, the effectiveness of observational practice for bimanual coordination skills is debated. We compared the behavioural and brain causal connectivity patterns following three interventions: primary motor cortex stimulation (M1-tDCS), action-observation (AO) and a combined group (AO+M1-tDCS) when acquiring a bimanual, two-ball juggling skill. Thirty healthy young adults with no juggling experience were randomly assigned to either video observation of a skilled juggler, anodal M1-tDCS or video observation combined with M1-tDCS. Thirty trials of juggling were performed and scored after the intervention. Resting-state EEG data were collected before and after the intervention. Information flow rate was applied to EEG source data to measure causal connectivity. The two observation groups were more accurate than the tDCS alone group. In the AO condition, there was strong information exchange from (L) parietal to (R) parietal regions, strong bidirectional information exchange between (R) parietal and (R) occipital regions and an extensive network of activity that was (L) lateralized. The M1-tDCS condition was characterized by bilateral long-range connections with the strongest information exchange from the (R) occipital region to the (R) temporal and (L) occipital regions. AO+M1-tDCS induced strong bidirectional information exchange in occipital and temporal regions in both hemispheres. Uniquely, it was the only condition that was characterized by information exchange between the (R) frontal and central regions. This study provides new results about the distinct network dynamics of stimulating the brain for skill acquisition, providing insights for motor rehabilitation. Full article

Introduction: Advanced endoscopic therapy techniques have been developed and have created alternative treatment options to surgical therapy for several gastrointestinal diseases. This work will focus on new endoscopic tools for special indications of advanced endoscopic resections (ER), especially endoscopic submucosal dissection (ESD), which were developed in our institution. This paper aims to analyze these specialized instruments and identify their status. Methods: Initially, the technical process of ESD was analyzed, and the following limitations of the different endoscopic steps and the necessary manipulations were determined: the problem of traction–countertraction, the grasping force needed to pull on tissue, the instrument tip maneuverability, the limited angulation/triangulation, and the mobility of the scope and instruments. Five instruments developed by our team were used: the Endo-dissector, additional working channel system, external independent next-to-the-scope grasper, 3D overtube working station, and over-the-scope grasper. The instruments were used and applied according to their special functions in dry lab, experimental in vivo, and clinical conditions by the members of our team. Results: The Endo-dissector has a two-fold function: (1) grasping submucosal tissue with enough precision and strength to pull it off the surrounding mucosa and muscle, avoiding damage during energy application and (2) effectively dividing tissue using monopolar energy. The AWC system quickly fulfills the lack of a second working channel as needed to complete the endoscopic task on demand. The EINTS grasper can deliver a serious grasping force, which may be necessary for a traction–countertraction situation during endoscopic resection for lifting a larger specimen. The 3D overtube multifunctional platform provides surgical-like work with bimanual-operated instruments at the tip of the scope, which allows for a coordinated approach during lesion treatment. The OTSG is a grasping tool with very special features for cleaning cavities with debris. Conclusions: The research and development of instruments with special features can solve unmet needs in advanced endoscopic procedures. The latter may help to increase indications for the endoscopic resections of gut lesions in the future. Full article

The purpose of this study was to quantify characteristics of bimanual movement intensity during 30 h of hand–arm bimanual intensive therapy (HABIT) and bimanual performance (activities and participation) in real-world settings using accelerometers in children with unilateral cerebral palsy (UCP). Twenty-five children with UCP participated in a 30 h HABIT program. Data were collected from bilateral wrist-worn accelerometers during 30 h of HABIT to quantify the movement intensity and three days pre- and post-HABIT to assess real-world performance gains. Movement intensity and performance gains were measured using six standard accelerometer-derived variables. Bimanual capacity (body function and activities) was assessed using standardized hand function tests. We found that accelerometer variables increased significantly during HABIT, indicating increased bimanual symmetry and intensity. Post-HABIT, children demonstrated significant improvements in all accelerometer metrics, reflecting real-world performance gains. Children also achieved significant and clinically relevant changes in hand capacity following HABIT. Therefore, our findings suggest that accelerometers can objectively quantify bimanual movement intensity during HABIT. Moreover, HABIT enhances hand function as well as activities and participation in real-world situations in children with UCP. Full article

In this study, we developed a new haptic–mixed reality intravenous (HMR-IV) needle insertion simulation system, providing a bimanual haptic interface integrated into a mixed reality system with programmable variabilities considering real clinical environments. The system was designed for nursing students or healthcare professionals to practice IV needle insertion into a virtual arm with unlimited attempts under various changing insertion conditions (e.g., skin: color, texture, stiffness, friction; vein: size, shape, location depth, stiffness, friction). To achieve accurate hand–eye coordination under dynamic mixed reality scenarios, two different haptic devices (Dexmo and Geomagic Touch) and a standalone mixed reality system (HoloLens 2) were integrated and synchronized through multistep calibration for different coordinate systems (real world, virtual world, mixed reality world, haptic interface world, HoloLens camera). In addition, force-profile-based haptic rendering proposed in this study was able to successfully mimic the real tactile feeling of IV needle insertion. Further, a global hand-tracking method, combining two depth sensors (HoloLens and Leap Motion), was developed to accurately track a haptic glove and simulate grasping a virtual hand with force feedback. We conducted an evaluation study with 20 participants (9 experts and 11 novices) to measure the usability of the HMR-IV simulation system with user performance under various insertion conditions. The quantitative results from our own metric and qualitative results from the NASA Task Load Index demonstrate the usability of our system. Full article

The smooth movement of hand/surgical instruments is considered an indicator of skilled, coordinated surgical performance. Jerky surgical instrument movements or hand tremors can cause unwanted damages to the surgical site. Different methods have been used in previous studies for assessing motion smoothness, causing conflicting results regarding the comparison among surgical skill levels. We recruited four attending surgeons, five surgical residents, and nine novices. The participants conducted three simulated laparoscopic tasks, including peg transfer, bimanual peg transfer, and rubber band translocation. Tooltip motion smoothness was computed using the mean tooltip motion jerk, logarithmic dimensionless tooltip motion jerk, and 95% tooltip motion frequency (originally proposed in this study) to evaluate their capability of surgical skill level differentiation. The results revealed that logarithmic dimensionless motion jerk and 95% motion frequency were capable of distinguishing skill levels, indicated by smoother tooltip movements observed in high compared to low skill levels. Contrarily, mean motion jerk was not able to distinguish the skill levels. Additionally, 95% motion frequency was less affected by the measurement noise since it did not require the calculation of motion jerk, and 95% motion frequency and logarithmic dimensionless motion jerk yielded a better motion smoothness assessment outcome in distinguishing skill levels than mean motion jerk. Full article

Integrating physical activity interventions at the workplace can have positive effects on the employees’ health. This study aimed to evaluate a physical activity break with coordinative exercises (PAB) including juggling and balance tasks and to assess its effects on motor abilities. Thirty-two university employees were randomly allocated to an intervention (IG:20) or a control (CG:12) group. The IG participated two times per week for 12 weeks in a PAB with a duration of 15 to 20 min. We measured the unimanual, bimanual finger, and hand dexterity with the Purdue Pegboard Test, the reaction time with the Fall Stick Test, and the dynamic balance with the Y Balance Test. Juggling performance was assessed by measuring the time(s) of performing a three-ball-cascade. Furthermore, an evaluation of the PAB was executed. Participants in the IG improved their juggling performance after six and twelve weeks. These increases were significantly different compared to the CG. However, no other parameters changed significantly. The evaluation showed that the PAB was enjoyable and led to subjective improvements in the participants health and working routine. To conclude, PAB can lead to improvements in juggling performance, subjective health, and the working routine. Full article

This study explored the biological autonomy and control of function in circumstances that assessed the presumed relationship of an organism with an environmental cycle. An understanding of this behavior appeals to the organism–environment system rather than just the organism. Therefore, we sought to uncover the laws underlying end-directed capabilities by measuring biological characteristics (motor synchrony) in an environmental cycle (circadian temperature). We found that the typical elementary coordination (bimanual) stability measure varied significantly as a function of the day–night temperature cycle. While circadian effects under artificially manipulated temperatures were not straightforward during the day–night temperature cycle, the circadian effect divided by the ordinary circadian rhythm remained constant during the day–night cycle. Our observation of this direct, robust relationship between the biological characteristics (body temperature and motor synchrony) and environmental processes (circadian temperature cycle) could mirror the adaptation of our biological system to the environment. Full article

With aging comes degradation of bimanual movement performance. A hallmark feature of bimanual movements is movement-related beta desynchronization (MRBD), an attenuation in the amplitude of beta oscillations associated with sensorimotor activation. Here, we investigated MRBD in 39 healthy adults (20 younger and 19 older adults) in frontal, central, and parietal regions across both hemispheres, during the planning and execution of a bimanual tracking task. Task accuracy decreased with age and during more difficult conditions when both hands had to move at different relative speeds. MRBD was mostly situated in the central region, and increased in older versus younger adults during movement execution but not planning. Irrespective of age, motor planning and execution were associated with increased MRBD in the left and right hemispheres, respectively. Notably, right central MRBD during motor planning was associated with bimanual task performance, particularly in older adults. Specifically, persons who demonstrated high MRBD during motor planning performed better on the bimanual tracking task. Our results highlight the importance of lateralized MRBD during motor planning, thereby shining new light on previous research and providing a promising avenue for future interventions. Full article

Different music training involves different hand coordination levels and may have a significant influence on brain oscillation for the executive function. However, few research has focused on the plasticity of executive function and the brain oscillation modulated by different musical instrument training modules. In this study, we recruited 18 string musicians, 20 pianists, and 19 non-musicians to perform a bimanual key pressing task during EEG recording. Behavioral results revealed that pianists have the highest accuracy and the shortest response time, followed by string musicians and non-musicians (p < 0.05). Time-frequency analyses of EEG revealed that pianists generated significantly greater theta power than the other groups from 500 ms to 800 ms post-stimulus in mid-central, frontal brain areas, and motor control areas. Functional connectivity analyses found that the pianists showed significantly greater connectivity in the frontal-parietal area in theta band based on phase-locking value analysis, which suggests that piano training improves executive function and enhances the connectivity between prefrontal and mid-central regions. These findings contribute to a better understanding of the effects of different music training on executive function. Full article