Concrete Pump Articulated Arm Geometry Control for Safe TCP Motion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Controlling the articulated arm of a concrete pump is complex due to multiple rotational degrees of freedom in a three-dimensional workspace, leading to a high risk of uncontrolled movement of the end hose and potential endangerment of construction site personnel, especially with single-axis control.
Innovation Solution
An articulated arm control system that includes a geometry control module, which solves an optimization problem to determine a trajectory for the movement of the lathe and joints, minimizing deviations from target configurations and taking into account system and environmental restrictions, including hydraulic limitations and collision avoidance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If single-axis control is used for the articulated arm, then the control system is simpler, but the risk of uncontrolled movement of the end hose increases and operator safety deteriorates
Solution Approach 1:
The control system continuously receives feedback from sensors monitoring the actual position and movement of the articulated arm segments. This feedback is processed to generate corrective control signals that prevent uncontrolled movement, thereby maintaining operator safety without requiring overly complex control architecture
Solution Approach 2:
The control system dynamically adjusts control parameters and trajectories in real-time based on the current state of the articulated arm and external conditions. This dynamic adaptation allows the system to maintain safety while managing complexity through intelligent, state-dependent control strategies
2Manufacturing precision
If geometry control with optimization problem solving is implemented, then the precision of TCP movement improves, but the computational time and processing requirements increase
Solution Approach 1:
The system pre-calculates and stores optimal trajectories and control parameters for common articulation configurations. When operating, the controller retrieves and adapts these pre-computed solutions rather than solving optimization problems from scratch, significantly reducing computational time while maintaining precision
Solution Approach 2:
The optimization approach dynamically adjusts problem parameters and constraints based on the current operational context. By changing parameters such as weighting factors, constraint tightness, and search space boundaries according to the situation, the system achieves high precision efficiently without excessive computational overhead
3Measurement precision
If multiple sensors are added to monitor articulated arm position and joints, then the control precision improves, but the system complexity and cost increase
Solution Approach 1:
The control system uses a multi-functional sensor suite where each sensor serves multiple purposes. For example, encoders on joints not only measure joint angles for position control but also provide data for collision detection, stability monitoring, and trajectory verification, thereby achieving high measurement precision without proportionally increasing system complexity
Solution Approach 2:
The system combines multiple measurement functions into integrated sensor assemblies and unified processing algorithms. By merging position sensing, velocity estimation, and configuration monitoring into a cohesive sensor-processing framework, the system achieves comprehensive measurement precision while minimizing the actual number of discrete sensors and processing channels required
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The present invention relates to an articulated arm control system for the articulated arm of a concrete pump, wherein the articulated arm has a swivel base rotatable about a vertical axis and at least two segments pivotable about horizontal axes by means of joints, wherein the swivel base is movable about the vertical axis via an actuator and the segments are pivotable about the horizontal axes via actuators, wherein sensors are preferably provided for determining the rotation angle of the swivel base and for determining the joint angles of the joints, wherein the articulated arm control system serves to control the actuators and comprises a geometry control system which generates a trajectory with target values for movement of the swivel base and/or the joints from input values for a target TCP movement.The geometry control is designed to determine the trajectory by solving an optimization problem, where the optimization problem has as its first objective function a deviation between the target TCP movement and a TCP movement resulting from the trajectory in a physical model of the articulated arm, and as its second objective function a deviation of a configuration of the articulated arm from a target configuration.