Concrete Pump Boom Vibration Control via Feedforward
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Concrete pumps face significant vibrations during concrete delivery, which affect the manageability and functionality of the equipment, particularly due to the slenderness and inertia of segments and the elastic properties of materials, leading to operator challenges and potential machine damage.
Innovation Solution
A concrete pump with a control system that applies disturbance variables based on a physical model of concrete delivery, including frictional and inertial forces, to reduce vibrations by controlling the actuators of the distribution boom, without the need for feedback from the vibration state of the boom.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If the articulated arm segments are made slender to achieve better positioning precision and extended reach, then the placing precision and reach are improved, but the vibrations induced by concrete delivery increase significantly
Solution Approach 1:
The control system applies preliminary anti-action by calculating disturbance forces from a physical model of concrete delivery and generating counteracting control signals before the vibrations occur. The disturbance variable feedforward control computes the expected vibrations based on pump operating parameters and articulated arm configuration, then applies compensating forces through the actuators to prevent vibration excitation rather than reacting after vibrations occur.
Solution Approach 2:
The system uses feedback by continuously monitoring the actual position and orientation of the articulated arm segments through sensors, comparing them with the desired positions from the physical model, and adjusting the actuator commands to minimize deviations. This closed-loop control ensures that placing precision is maintained while the feedforward component compensates for vibration-inducing forces.
2Ease of operation
If the articulated arm segments are made lighter to reduce inertia and improve maneuverability, then the ease of operation is improved, but the vibrations and stability issues worsen
Solution Approach 1:
The disturbance variable feedforward control calculates the inertial forces and moments that will result from the lightweight articulated arm's acceleration and deceleration, based on the physical model. The control system applies counteracting forces through the actuators before these inertial effects cause excessive vibrations, allowing lightweight segments to be used without compromising stability.
Solution Approach 2:
The system performs preliminary action by pre-calculating the optimal actuator commands that achieve the desired motion trajectory while minimizing vibration excitation. The physical model predicts the dynamic response of the lightweight articulated arm, and the control system prepares compensating forces in advance, allowing the lightweight structure to operate smoothly without excessive vibrations.
3Productivity
If the pump frequency is increased to improve productivity, then the concrete delivery speed is improved, but the vibrations of the placing boom increase excessively
Solution Approach 1:
The disturbance variable feedforward control calculates the disturbance forces generated by the pump's delivery action based on the physical model of concrete flow and pipe dynamics. When pump frequency is increased for higher productivity, the control system computes the resulting vibrations and applies counteracting forces through the articulated arm actuators, allowing high-speed delivery without excessive boom vibrations.
Solution Approach 2:
The system dynamically adjusts the control parameters of the articulated arm actuators based on the pump operating frequency. The physical model provides real-time predictions of vibration forces at different pump frequencies, and the control system modifies actuator commands accordingly, enabling the system to operate at high productivity levels while maintaining vibration levels within acceptable limits through parameter optimization.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach effectively reduces vibrations induced by concrete delivery, improving the manageability and functionality of the concrete pump by compensating for disruptive forces before they cause significant oscillations, thus enhancing operator control and extending equipment lifespan.
Implementation Method 1
the physical model describes frictional forces of the concrete against the inner wall of the concrete pipe
Implementation Method 2
inertial forces due to the deflection of the concrete flow in the pipe bends
Data Source
Figure 1
Figure 2~3
Figure 4~5
AI summary
The present invention relates to a concrete pump, in particular a truck-mounted concrete pump, comprising a delivery pump, a concrete line and an articulated arm forming a placing boom, along which the concrete line is guided, wherein the articulated arm has a swivel base rotatable about a vertical axis and/or at least one segment pivotable about a horizontal axis by means of a joint, wherein the swivel base is movable about the vertical axis via an actuator and/or the at least one segment is pivotable about the horizontal axis via an actuator, wherein the concrete pump further comprises a control system for controlling the actuators of the placing boom, wherein the control system includes a disturbance variable feedforward to reduce the vibrations of the placing boom induced by the concrete delivery.It is characterized by the fact that the disturbance variable feed-in is based on a physical model of concrete conveying, which describes the flow-related disturbance forces of the concrete conveying on the distribution mast.