机器人学基础 第6章 机器人传感器 蔡自兴

Compound Force: detect forces along multiple directions.
Proximity: non-contact detection of objects. Simple Vision: detect feature such as holes, lines, and corners. Compound Vision: recognition of object.
6.1 Introduction to Robot Sensors
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6.1 Introduction to Robot Sensors 6.2 Internal Sensors（内部传感器）
6.3 External Sensors（外部传感器）
6.4 Robot Sensor Application Considerations
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6.1.1 Classification of Robot Sensors Most needed sensory abilities for robot:
Simple Touch: detect whether the object is there or not. Compound Touch: detect the size and shape of the object. Simple Force: detect force along one direction.
6.2 Internal Sensors
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2．Relative Angle Sensor
In this approach, no matter the clockwise (CW) rotation, or counter-clockwise (CCW) rotation, output of the sensing light always alternate between H and L, so we can not get the direction of rotation.
6.2 Internal Sensors
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2．Relative Angle Sensor
Adding another sensor (B) 1/4 cycle away from sensor A. Typically, when clockwise (CW) rotation, signal A changes before B, vice versa.
a)光电位置传感器
b) 感光量曲线
6.2 Internal Sensors
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6.2.2 Angle Sensors
1．Absolute Optical Angle Sensor For example, resolution of a 12 bit encoder is 2-12 = 4096, so we have光学式绝对型旋转编码器 a round of 360 degrees). a resolution of 1 / 4096 (for
6.1 Introduction to Robot Sensors
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6.1.1 Classification of Robot Sensors Robot sensors can be divided into two main categories: Internal state
Detect position and orientation in the coordinate of the robot itself, deal with the detection of variables such as arm joint position, velocity, and acceleration.
6.2 Internal Sensors
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1．Gyro Sensor 陀螺仪 A gyroscope is a device for measuring or maintaining orientation, based on the principles of conservation of angular momentum.
Environment
Camera 1
Camera 2
Ultrasonic
InfraRed
ForБайду номын сангаасe Sensor
Tactile Sensor
Stereo Vision
Landmark Detection
Obstacle Detection
Target Detection
Natural Object Recognition
Shown right is a rate gyro.
1—电动机2—角度传感器3—转子4一弹簧
6.2 Internal Sensors
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2．Other Gyros
gas rate gyroscope 气体速率陀螺仪 optical gyroscope 光陀螺仪 piezoelectric vibratory gyroscope 压电振动式陀螺 (shown on the right)
6.2 Internal Sensors
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1．Absolute Optical Angle Sensor Absolute rotary encoders can also be used to detect angular velocity. By comparing current value and stored values, we can obtain the corresponding angular velocity.
6.2 Internal Sensors
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6.2.3 Attitude Sensors 姿态传感器
Attitude sensors are used to detect the relative relationship between the robot and ground. When the robot is fixed (just as the majority of industrial robot), there is no need to install such sensors. Attitude sensors are essential for mobile robots. Attitude sensors detect moving changes in position and orientation of the robot that can be used to control the robot implement desired instruction.
External state
Localize the robot to the environment, deal with the detection of variables such range, proximity, and touch.
6.1 Introduction to Robot Sensors
a) 导电塑料型
b) 线圈型
6.2 Internal Sensors
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3. Electro-optical Position Sensor
Find the relationship between the distance and the received light volume (shows in Fig. b) in advance, we can measure the displacement x of the light source.
Fusion
Internal Sensor
Sensory Ability
Environmental Model
Localization
Obstacle Avoidance
Operation Planning
Learning
Trajectory Planning
Task Planning
Instruction
6.5 Summary
Ch.6 Robot Sensors
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6.2 Internal Sensors
6.2.1 Position/Displacement Sensors 位置传感器
A position sensor is any idea that permits position measurement. It can either be an absolute position sensor or a relative one (displacement sensor). Position sensors can be either linear or angular. Inductive Non-Contact Position Sensors, String Potentiometer, Linear variable differential transformer (LVDT) , Potentiometer, Capacitive transducer, Hall effect sensor, Proximity sensor (optical), Grating sensor, Rotary encoder (angular), Photodiode array, etc.
6.2 Internal Sensors
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6.2.1 Displacement/Position Sensors 1. Linear Potentiometer 线性电位计
Consists of a wirewound resistor (or a thin film resistor), and a sliding contact point.