Walking Control Method for Bipedal Robots Using Multi-Mass Point Segmentation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing bipedal walking robot control methods fail to effectively control walking speed and maintain stability when disturbances occur, as they rely on single-mass point models that do not account for the dynamics of swing leg motion and distributed mass, leading to errors in following target speeds and potential falls.
Innovation Solution
A walking control method that decomposes the robot into multiple mass points, constrains the motion of these points to maintain a conservative system, and adjusts energy to control walking speed by generating constraint trajectories for the swing leg, ensuring robustness during disturbances.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single-mass point model is used for walking control, then the control system is simple, but the walking speed control precision deteriorates when leg mass is not negligible
Solution Approach 1:
The robot body is segmented into multiple mass points including the main body mass point and swing leg mass point. This segmentation allows the control system to account for the distributed mass of the swing leg while maintaining a manageable control structure. The multi-mass point model captures the dynamics more accurately without requiring full complex rigid-body dynamics.
Solution Approach 2:
The invention changes the modeling parameters from a single mass point to multiple mass points with specific constraints. By defining the swing leg mass point position as an affine transformation of the main body mass point position, the model incorporates leg mass effects while maintaining mathematical tractability for control design.
2Device complexity
If a conservative system model is used, then the mathematical model is simple, but the model accuracy deteriorates when swing leg motion dynamics are not considered
Solution Approach 1:
The conservative system is segmented into multiple mass points with the swing leg mass point explicitly included. This allows the model to capture swing leg dynamics while maintaining the energy conservation property of conservative systems, balancing simplicity and accuracy.
Solution Approach 2:
The invention introduces dynamic elements by including the swing leg mass point with affine transformation constraints. This adds the necessary dynamics of swing leg motion to the conservative system model without breaking the energy conservation framework, improving model accuracy.
3Ease of operation
If intermittent control is used to adjust trajectory energy, then the control is simple, but the walking speed following capability deteriorates when leg mass is significant
Solution Approach 1:
The intermittent control is applied to the multi-segmented mass point system rather than a single mass point. This allows energy adjustment to account for swing leg dynamics, improving speed following capability while maintaining the intermittent control framework and its simplicity.
Solution Approach 2:
The control method incorporates dynamic effects of the swing leg by using a multi-mass point model. The affine transformation constraints ensure that energy adjustments properly account for swing leg motion, enabling accurate speed following even when leg mass is significant.
4Ease of manufacture
If the swing leg mass is neglected in the model, then the control design is easier, but the robot stability deteriorates when disturbances occur
Solution Approach 1:
The robot is segmented into mass points that include the swing leg, allowing control design to account for swing leg dynamics. This improves disturbance rejection capability while maintaining reasonable control design complexity through the affine transformation framework.
Solution Approach 2:
The control design incorporates swing leg dynamics through the multi-mass point model with affine constraints. This enables the controller to properly account for angular momentum and dynamic effects during disturbances, improving stability while keeping the design tractable.
Data Source
AI summary
A walking control method of an embodiment includes decomposing a mobile device with legs into a plurality of mass points, decomposing the plurality of decomposed mass points into a first interest mass point and mass points other than the first interest mass point, making a length between the first interest mass point and a contact point on a walking plane constant, making the mass points other than the first interest mass point constrained to an affine-transformed position of the first interest mass point, and generating a constraint trajectory of the mass points other than the first interest mass point in accordance with the constraint when the first interest mass point is moved.