Resolver positioning system, robot and method therefor

Patent metadata

Field	Value
Publication number	US-9658084-B2
Application number	US-201214443988-A
Country	US
Kind code	B2
Filing date	Nov 19, 2012
Priority date	Nov 19, 2012
Publication date	May 23, 2017
Grant date	May 23, 2017

Abstract

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.

First claim

The invention claimed is:

1. A method for detecting a change in positing of an axis of a robot, comprising the following steps:
firstly, reading a first resolver value from a first comparator of a resolver positioning system, and reading a second resolver value from a second comparator of said resolver positioning system, wherein said first and second comparators are configured with a first reference value;
changing said first reference value to a second reference value different from said first reference value;
secondly, reading a first resolver value from said first comparator, and reading a second resolver value from said second comparator, wherein said first and second comparators are configured with the second reference value; and
detecting a change in position of an axis of a robot only when said first reading indicates a first new resolver value and said second reading indicates a second new resolver value that is the same as the first new resolver value.

2. The method according to claim 1 , wherein the changing step includes changing a resistance value of an input of said first and second comparators.

3. The method according to claim 1 , wherein a difference of the first and second reference values is set to at least a noise level of the first and second resolver values.

4. A resolver positioning system for a robot, which system is connectable to a battery supply and is drivable in a pulsed mode, said system comprising:
a resolver arranged to detect an axis position of a robot;
a first comparator connected to said resolver and configured to read a first resolver value from said resolver, wherein said first comparator is configured to provide two different reference levels for said first resolver value;
a second comparator connected to said resolver and configured to read a second resolver value from said resolver, wherein said second comparator is configured to provide two different reference levels for said second resolver value; and
a controller connected to said first and second comparators, wherein said controller is configured to provide a quadrant evaluation of said axis position from said first and second resolver values, and wherein said controller is configured to change between the two reference levels of said first comparator and said second comparator between two consecutive readings of said first resolver value and said second resolver value, respectively.

5. The resolver positioning system according to claim 4 , comprising a first resistor connected to an input of said first comparator and a second resistor connected to an input of said second comparator.

6. The resolver positioning system according to claim 4 , wherein a difference between the two different reference levels are at least equal to a noise level of said first resolver value and second resolver value, respectively.

7. The resolver positioning system according to claim 4 , wherein said controller is configured to increase a sampling frequency of said resolver positioning system when a change of axis position is determined.

8. The resolver positioning system according to claim 4 , wherein said controller is configured to detect a change in axis position only when two consecutive readings of said first and second comparators, separated by a change of reference level, both indicate a new resolver value.

9. A robot drivable in pulsed mode, comprising a battery supply and a resolver positioning system according to claim 4 .

10. The method according to claim 1 , wherein the first and second comparators each include two analog input terminals and one binary digital output terminal; and
wherein the method further comprises inputting a respective analog comparator signal into each of the two analog input terminals of the first and second comparators.

11. The resolver positioning system of claim 4 , wherein the first comparator and the second comparator each include two analog input terminals and one binary digital output terminal.

Assignees

• Abb Schweiz Ag

Inventors

• Jonsson Ingvar

Classifications

• G01D5/20 Primary

  by varying inductance, e.g. by a movable armature · CPC title

• G01D5/204 Primary

  by influencing the mutual induction between two or more coils (G01D5/22 takes precedence) · CPC title

• G01B7/004

  for measuring coordinates of points · CPC title