Movement detection device, electronic device, movement detection method and computer readable medium

• US 20110208472A1
• Filed: 02/18/2011
• Published: 08/25/2011
• Est. Priority Date: 02/22/2010
• Status: Active Grant

• Current Assignee: LAPIS Semiconductor Co., Ltd. (ROHM Co., Ltd.)
• Original Assignee: Oki Semiconductor Company Limited (ROHM Co., Ltd.)
• Inventors: Fujiwara, Kazunori
• Granted Patent: US 8,793,098 B2
• Time in Patent Office: Days
• US Class Current: 702/141
• CPC Class Codes: G01P 13/04 Indicating positive or negative direction of a linear movement or clockwise or anti-clockwise direction of a rotational movement
• CPC Class Codes: G01P 15/18 in two or more dimensions
• CPC Class Codes: G06F 3/017 Gesture based interaction, e.g. based on a set of recognized hand gestures interaction based on gestures traced on a digitiser G06F3/04883
• CPC Class Codes: G06F 3/0346 with detection of the device orientation or free movement in a 3D space, e.g. 3D mice, 6-DOF [six degrees of freedom] pointers using gyroscopes, accelerometers or tilt-sensors
• CPC Class Codes: H04M 2250/12 including a sensor for measuring a physical value, e.g. temperature or motion telephones including GPS signal receivers H04M2250/10

Abstract

Tri-axial acceleration component data detected by a tri-axial acceleration sensor of acceleration acting on a movement detection device is split into respective stationary components obtained by low-pass filtering processing and movement components of the acceleration component data from which the respective stationary component has been removed. Which axial direction has been moved in is detected based on the split movement component expressing the maximum value. A shake duration is detected as a period of time from the point in time when this maximum movement component exceeded a threshold value expressing an upper limit value of a specific range up to once again becoming a value in the specific range after becoming less than a threshold value expressing a lower limit value, or as a period of time from the point in time when the movement component became less than the lower threshold value up to once again becoming a value in the specific range after exceeding the upper threshold value. The magnitude of movement is determined by whether or not the shake duration is a determination period or longer, or by whether or not the vector integral value over the shake duration is a determination threshold value or greater.

Claims

1. A movement detection device comprising an acceleration detection section and a movement detection section, wherein:

the acceleration detection section detects each respective acceleration component of acting acceleration for each axis of a three-dimensional orthogonal coordinate system and outputs respective acceleration component data;

the movement detection section detects an axial direction in which the acceleration component has moved along the respective axes based on acceleration component data output from the acceleration detection section;

for cases in which the acceleration component data of the given axial direction exceeded an upper limit value of a specific range encompassing 0 before becoming less than a lower limit value of the specific range, the movement detection section detects the magnitude of movement based on a first time period from a point in time when the acceleration component data exceeded the upper limit value up to once again becoming a value in the specific range after becoming less than the lower limit value, or based on a first integral value of the magnitude of the acceleration component within the first time period; and

for cases in which the acceleration component exhibiting a maximum value became less than the lower limit value before exceeding the upper limit value, the movement detection section detects the magnitude of movement based on a second time period from a point in time when the acceleration component became less than the lower limit value up to once again becoming a value within the specific range after exceeding the upper limit value, or based on a second integral value of the magnitude of the acceleration component within the second time period.

2. The movement detection device of claim 1, further comprising a splitting section that splits the respective acceleration component data output from the acceleration detection section into a stationary component obtained by low-pass filter processing and a movement component that is the respective acceleration component data from which the respective stationary component has been removed, wherein the movement detection section detects an axial direction in which the acceleration component has moved along the respective axes based on the movement component split by the splitting section expressing the maximum value.

3. The movement detection device of claim 2, wherein:

for cases in which the movement component expressing the maximum value for movement of the acceleration detection section to and from along one of the axial directions has first exceeded the upper limit value before becoming less than the lower limit value, the movement detection section detects the acceleration detection section as having moved in the axial direction corresponding to the movement component expressing the maximum value when a period of time from the point in time the movement component exceeded the upper limit value up to becoming less than the lower limit value is longer than a predetermined specific duration; and

for cases in which the movement component expressing the maximum value has become less than the lower limit value before exceeding the upper limit value, the movement detection section detects the acceleration detection section as having moved in the axial direction corresponding to the movement component expressing the maximum value when a period of time from the point in time the movement component became less than the lower limit value up to exceeding the upper limit value is longer than the predetermined specific duration.

4. The movement detection device of claim 1, further comprising a splitting section, wherein;

the splitting section splits the respective acceleration component data output from the acceleration detection section into a stationary component obtained by low-pass filter processing and a movement component that is the respective acceleration component data from which the respective stationary component has been removed;

the movement detection section detects whether which of the axes is an gravitational axis corresponding to the direction of gravity based on the stationary component when the acceleration detection section has been moved in the direction of gravity with one of the axes facing in the direction of gravity; and

the movement detection section detects the magnitude of movement based on the movement component in the axial direction.

5. The movement detection device of claim 4, wherein:

for cases in which the movement component of the gravitational axis first exceeded the upper limit value before becoming less than the lower limit value, the movement detection section detects the acceleration detection section as having moved in the direction of gravity when a period of time from the point in time the upper limit value was exceeded up to becoming less than the lower limit value is longer than a predetermined specific duration; and

for cases in which the movement component of the gravitational axis became less than the lower limit value before exceeding the upper limit value, the movement detection section detects the acceleration detection section as having moved in the direction of gravity when a period of time from the point in time the movement component became less than the lower limit value up to exceeding the upper limit value is longer than the predetermined specific duration.

6. The movement detection device of claim 1, wherein the movement detection section detects the level of the magnitude of movement by:

comparing the first time period or the second time period against a plurality of predetermined determination periods, and determining whether the first time period or the second time period is longer than one of the plurality of determination periods;

or, by comparing the first integral value or the second integral value against a plurality of predetermined determination values, and detecting whether the first integral value or the second integral value are greater than one of the plurality of predetermined determination values.

7. An electronic device comprising the movement detection device of claim 1.

8. A movement detection method comprising:

detecting with an acceleration detection section each respective acceleration component of acceleration acting on the acceleration detection section for each axis of a three-dimensional orthogonal coordinate system and outputting respective acceleration component data;

detecting with the acceleration detection section an axial direction in which the acceleration component has moved along the respective axes based on output acceleration component data;

for cases in which the acceleration component data of the detected axial direction exceeded an upper limit value of a specific range encompassing 0 before becoming less than a lower limit value of the specific range, detecting the magnitude of movement with a movement detection section based on a first time period from a point in time when the acceleration component data exceeded the upper limit value up to once again becoming a value in the specific range after becoming less than the lower limit value, or based on an integral value of the magnitude of the acceleration component within the first time period; and

for cases in which the acceleration component exhibiting the maximum value became less than the lower limit value before exceeding the upper limit value, detecting the magnitude of movement with the movement detection section based on a second time period from a point in time when the acceleration component became less than the lower limit value up to once again becoming a value within the specific range after exceeding the upper limit value, or based on an integral value of the magnitude of the acceleration component over the second time period.

9. A computer readable storage medium stored with a movement detection program that causes a computer to function as:

an acquisition section that acquires-respective acceleration component data output from an acceleration detection section that detects respective acceleration component of acting acceleration for each axis of a three-dimensional orthogonal coordinate system and outputs the respective acceleration component data; and

a movement detection section that detects an axial direction in which the acceleration component has moved along the respective axes based on acceleration component data output from the acceleration detection section acquired by the acquisition section, and

for cases in which the acceleration component data of the detected axial direction exceeded an upper limit value of a specific range encompassing 0 before becoming less than a lower limit value of the specific range, detecting the magnitude of movement based on a first time period from a point in time when the acceleration component data exceeded the upper limit value up to once again becoming a value in the specific range after becoming less than the lower limit value, or based on an integral value of the magnitude of the acceleration component within the first time period, and

for cases in which the acceleration component exhibiting the maximum value became less than the lower limit value before exceeding the upper limit value, detecting the magnitude of movement based on a second time period from a point in time when the acceleration component became less than the lower limit value up to once again becoming a value within the specific range after exceeding the upper limit value, or based on an integral value of the magnitude of the acceleration component within the second time period.