Resolver Positioning System for Robot Axis Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing resolver positioning systems for industrial robots require high energy consumption, leading to the need for large and costly batteries, and are complicated due to the requirement of multiple resolvers and extensive cable arrangements, which increases the complexity and cost of the system.
Innovation Solution
A resolver positioning system that uses a pulse generator to send pulses to an excitation coil in a resolver, with signals processed by comparators to determine the quadrant position, allowing for reduced power consumption by minimizing sampling frequency and verifying axis movement only after two quadrant changes, thereby reducing battery current and enabling the use of smaller, cheaper batteries.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If continuous sampling of resolver signals is used to ensure accurate position detection, then measurement precision is improved, but energy consumption increases
Solution Approach 1:
The system performs resolver signal sampling periodically at reduced intervals instead of continuously. The control unit samples the resolver signals only at specific time points determined by pulse transitions from the pulse transducer, thereby maintaining adequate measurement precision while dramatically reducing energy consumption during battery operation.
Solution Approach 2:
The sampling frequency of the resolver position transducer is made dynamically adjustable based on system state. During battery-powered operation, the sampling rate is automatically reduced compared to mains-powered operation, allowing the system to adapt its energy consumption to available power sources while maintaining sufficient positioning accuracy.
2Measurement precision
If two resolvers are used per robot axis to achieve absolute measurement, then measurement precision is improved, but device complexity increases
Solution Approach 1:
The system combines a single resolver with a pulse transducer into an integrated positioning system. The resolver provides high-resolution angular position within each revolution, while the pulse transducer provides absolute revolution counting. By merging these two transducer types and using their outputs together in the control unit, the system achieves absolute position measurement equivalent to dual-resolver systems but with reduced component count and complexity.
Solution Approach 2:
The control unit acts as an intermediary that processes and combines signals from both the resolver and pulse transducer. It integrates the high-resolution incremental data from the resolver with the absolute revolution count from the pulse transducer to compute the complete absolute position, eliminating the need for extensive cable arrangements and complex external processing hardware.
3Speed
If high sampling frequency is used to detect axis movement quickly, then response speed is improved, but energy consumption increases
Solution Approach 1:
The system uses feedback from the pulse transducer to trigger resolver sampling only when actual axis movement occurs. The pulse transducer detects pulse transitions indicating axis movement and triggers the control unit to sample the resolver signals at these specific moments, ensuring rapid movement detection while avoiding continuous high-frequency sampling that would waste energy during stationary periods.
Solution Approach 2:
Instead of maintaining constant high sampling frequency, the system applies partial sampling action only when needed. By sampling resolver signals only at pulse transitions detected by the pulse transducer rather than continuously, the system achieves adequate movement detection speed with significantly reduced energy consumption during battery-powered operation.
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
The system significantly reduces battery current consumption by 0.41 times, allowing for the use of smaller and cheaper batteries while maintaining accurate axis position detection, and simplifies the system by eliminating the need for multiple resolvers and extensive cable arrangements.
Implementation Method 1
a resolver arranged to detect an axis position of a robot
Implementation Method 2
a first comparator connected to the resolver for reading of a first resolver value from the resolver, wherein the first comparator comprises means to provide two different reference levels for the first resolver value; a second comparator connected to the resolver for reading of a second resolver value from the resolver
Data Source
AI summary
The present invention relates to a resolver positioning system for a robot, which system is connectable to a battery supply (402) and is drivable in a pulsed mode. The system comprising: a resolver (32) arranged to detect an axis position of a robot; a first comparator (80, 81) connected to the resolver for reading of a first resolver value from the resolver, wherein the first comparator comprises means (82-87) to provide two different reference levels for the first resolver value; a second comparator (80, 81) connected to the resolver for reading of a second resolver value from the resolver, wherein the second comparator comprises means (82-87) to provide two different reference levels for the second resolver value; and a controller (20) connected to the first and second comparators, wherein the controller is configured to provide a quadrant evaluation of the axis position from the first and second resolver values.