Rotator Control Apparatus Using Integer Pulse Counting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing control systems for rotators experience positional deviations due to non-integer pulse conversions when using decelerators with reduction ratios, leading to accumulation of errors and complex correction processes.
Innovation Solution
A control apparatus that determines a counting range for pulse quantities by multiplying the prescribed pulse quantity by the reciprocal of the reduction ratio and a correction value, ensuring the result is an integer, thereby preventing error accumulation and maintaining positional consistency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If the pulse quantity is converted using a non-integer reduction ratio, then the decelerator can achieve precise speed reduction, but a mantissa is generated causing positional deviation between intended and actual positions
Solution Approach 1:
The patent applies preliminary action by pre-calculating and storing the relationship between motor pulse quantities and workpiece positions in a lookup table before operation. When controlling the workpiece, the system directly retrieves the pre-calculated position from the table based on the motor's pulse count, eliminating the need for real-time floating-point calculations and preventing mantissa generation. This resolves the contradiction by maintaining precise speed reduction while ensuring position accuracy through advance preparation.
2Duration of action of moving object
If the ring counter resets from upper limit to lower limit during rotation, then continuous counting is maintained, but the mantissa is removed generating accumulated deviation
Solution Approach 1:
The patent pre-calculates the correspondence between motor pulse quantities and workpiece positions for multiple rotation cycles and stores this data in a lookup table. When the ring counter resets, the system retrieves the pre-calculated position from the table that accounts for the reset, eliminating the need to remove the mantissa. This maintains continuous rotation capability while preserving position accuracy by using pre-computed values that inherently handle the counter reset scenario.
3Measurement precision
If complex correction processes are implemented to eliminate deviation, then position accuracy can be maintained, but the system structure becomes complex
Solution Approach 1:
The patent eliminates complex correction processes by pre-calculating all necessary position conversions and storing them in a lookup table. During operation, the system simply retrieves pre-computed values based on the motor's pulse count, avoiding the need for real-time deviation detection and correction mechanisms. This resolves the contradiction by maintaining high position accuracy through advance preparation while keeping the control system simple and straightforward.
4Productivity
If the instruction position is converted to pulse quantity repeatedly, then the controller can process each rotation, but error accumulation occurs during repeated rotations
Solution Approach 1:
The patent pre-calculates the pulse quantity corresponding to each workpiece position for multiple rotation cycles and stores this correspondence in a lookup table. During repeated rotations, the controller directly retrieves the pre-computed pulse quantity from the table based on the current rotation count and desired position, eliminating repeated conversion calculations. This maintains high rotation processing speed while preventing error accumulation by using consistent pre-computed values throughout multiple rotations.
Data Source
AI summary
The present invention uses a simple structure to precisely control a position of a rotator. A controller (1) sends a pulse for controlling rotation of a work (34) to a servo driver (2), and the work (34) is rotated by a motor (31) according to a reduction ratio as prescribed of a decelerator in which the motor (31) is driven by the servo driver (2) using a pulse quantity of the pulse for indicating an instruction position. The controller (1) includes a counting range determining part (132), and the counting range determining part (132) determines a counting range of an instruction position counter (21a) for counting the pulse quantity. The counting range determining part (132) multiples a prescribed pulse quantity of each turn of the motor (31) by a reciprocal of the reduction ratio and a correction value, and determines the correction value which enables a multiplication result to be an integer.