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Does an exoskeleton really make me walk lighter? Why does an exoskeleton help lower my heart rate and reduce stress on my knees?

The core logic of exoskeletons in making walking lighter, lowering heart rate, and reducing knee joint stress (mechanical assistance to share muscle load → reduced energy consumption → decreased heart rate; optimized force line to distribute joint pressure → reduced load on the knee joint);   • **Sub-Principle 1 (Lighter Walking):** Breaks down the mechanical assist mechanism (lever effect, torque compensation, real-time sensor perception), such as "the exoskeleton's hip joint motor provides thrust when lifting the leg, sharing 50% of the thigh muscle load"; replacing the gastrocnemius and quadriceps muscles in exertion. Includes laboratory data on reduced muscle stress. • **Sub-Principle 2 (Lower Heart Rate):** Explains the physiological metabolic pathway (reduced muscle load → reduced oxygen uptake → reduced cardiovascular system stress → decreased heart rate), including data on decreased heart rate. • **Sub-Principle 3 (Reduced Knee Joint Pressure):** Analyzes biomechanical optimization (reduced knee adduction torque, force line dispersion, gait correction), such as "the flexible exoskeleton reduces knee adduction torque through hip abduction torque, reducing the risk of cartilage damage"; includes laboratory research papers. • **Implementation Supplement:** Supplements the impact of product design considerations (such as lightweighting and adaptability) on the effect, aligning with the product definition requirements. Includes product assist stability, assist fit to the human body, and terrain recognition. 1) The impact of structural stability on the assist       2) Impact on Human Body Matching Accuracy: AI Human Body Adaptation (Learning Algorithm) This point should be supplemented by information about the π6's camera. Terrain Recognition: This point should be added regarding the π6's camera.     (I)                               Definition of Weight Reduction and Assistance In the field of exoskeleton robots, "weight reduction" generally refers to the device actively bearing part of the user's weight load through mechanical structures (such as straps and support rods), reducing the pressure on the user's lower limb joints or muscles.  "Assistance" refers to the system providing additional torque or force to compensate for or enhance the user's voluntary muscle strength, usually quantified as the percentage of assistive force to the total required force.   (I) Mechanism and Principle of Achieving Weight Reduction and Assistance The core of the weight reduction mechanism is to transfer part of the body weight directly to the ground during the gait cycle (such as the middle of the standing phase) through the rigid frame and intelligent joints of the exoskeleton, thereby reducing the load on the user's knee and hip joints. 1.  Theoretical research indicates that optimized design can reduce the weight of the equipment to less than 5% of the user's weight, thus avoiding it becoming an additional burden. 2. The assist mechanism is primarily based on "human-machine interaction force" measurement and "assist torque" control. The system identifies the user's movement intention through sensors, and then a motor or elastic element outputs precise torque at the joint to share the work required by the muscles. The percentage of assistance can be determined by adjusting the ratio of the output torque to the estimated human joint torque. 3. Relevant Experiments and Quantitative Verification Regarding the weight loss effect, studies have confirmed through electromyography (Figure 1) that exoskeletons can significantly reduce the activation level of related muscles. Wearing a lower limb exoskeleton can reduce the activity of specific muscles by 36%-97%, and the reduction in muscle activity is directly related to the reduction in joint load. 4. Experiments have also shown that by directly measuring with force platforms and other equipment, the use of a specific passive exoskeleton can achieve a 27% weight load transfer during the peak foot phase of gait. Figure 1. Electromyography showing the effect of working height and exoskeleton on lower limb muscles. Regarding quantitative data on assistive effects, several independent studies have reported assistive effects ranging from 20% to 35%. For example, some soft exoskeletons have provided up to 35% power reduction in seated tasks. 5. Other studies have reported that an average of 20% assistance or handling tasks can reduce the median force by 27%. 6. Empirical Analysis of Relevant Application Cases   In clinical trial reports of ReWalk ReStore™ for stroke rehabilitation, the average plantar flexion assistance reached 92.0%. This strongly demonstrates that exoskeletons achieving 30% or even higher assistance rates in specific rehabilitation scenarios are supported by solid clinical data. ⑦ Furthermore, in an evaluation report from Yueyang Hospital of Integrated Traditional Chinese and Western Medicine affiliated with Shanghai University of Traditional Chinese Medicine (Figure 2), Kenqing Technology's exoskeleton robot provided significant assistance and support in common daily life scenarios such as walking, climbing stairs, and bending over. ⑧ Figure 2. Summary of body data changes when wearing the Kenqing Technology exoskeleton in different body scenarios.    References     ①　A Wearable Lower Limb Exoskeleton: Reducing the Energy Cost of Human Movement ②　Development of Knee Power Assist using Backdrivable Electro-Hydrostatic Actuator ③　Evaluation of the Effects of Passive Lower-Limb Exoskeletons on Muscle Activities                                       According to Working Heights ④　Development and Testing of Passive Walking Assistive Exoskeleton with Upward                                          Force Assist ⑤　Design and Evaluation of a Soft Assistive Lower Limb Exoskeleton ⑥　A case study on occupational back-support exoskeletons versatility in lifting and                                      carrying ⑦　The ReWalk ReStore™ soft robotic exosuit: a multi-site clinical trial of the safety,                                     reliability, and feasibility of exosuit-augmented post-stroke gait rehabilitation ⑧　https://mp.weixin.qq.com/s/fnKMD90KZgYXABV-WjcisA