Sensors
What are Sensors?
noun
a device which detects or measures a physical property and records, indicates, or otherwise responds to it.
"to ensure greater response and surer handling, the engineers used electronic sensors to monitor each wheel"
A sensor is a device that measures physical input from its environment and converts it into data that can be interpreted by either a human or a machine. Most sensors are electronic (the data is converted into electronic data), but some are more simple, such as a glass thermometer, which presents visual data.
Distance Sensor: 2M
The REV Robotics 2m Distance Sensor uses the ST Microelectronics VL53L0X Time-of-Flight (ToF) laser-ranging module to measure distances up to 2 meters with millimeter resolution. Unlike other ranging sensors that rely on the intensity of reflected light, this sensor can measure how long it takes for the light to bounce back, the "time of flight." This results in much more accurate measurements that are independent of the target's reflectance.
See our sample code for a REV 2M Distance Sensor here.
Specifications
Measurement Range: 5cm - 200cm
Measurement Resolution: 1mm
Field of View: 25°
Laser Type: 940nm (IR) Class 1
Sensor Type: I2C
I2C Address: 0x52
Voltage Range: 3.3V - 5.0V
Max. Operating Current: 40mA
Dimensions: 39.4mm x 16.5mm x 15mm
Mounting holes: 2 x M3 holes on 32mm pitch
Color Sensor: V3
This sensor can be used to read and compare colors, and also has a built-in IR (optical) Proximity Sensor and white LED for active target lighting. Supports High-Speed I2C Communication (400kHz), as well as auto-increment register, read which allows the user to return all the color register and status register data in one read command instead of 4 separate read commands.
Version 3 of the REV Color Sensor introduces a new sensor chip by Broadcom due to the end of life of the V1/V2 sensor. The physical form factor is the same as V2, however, there are some minor changes to the FTC SDK. Be sure to update to the latest SDK and configure your robot to use the "REV Color Sensor V3". Color values will not be consistent between V2 and V3 sensors.
See our sample code for a REV Color Sensor V3 here.
Specifications:
Max Operating Voltage: 3.3V
Sensor Type: I2C
I2C Address: 0x52
Color Sensor Part: APDS-9151
Measurement channels: Red, Green, Blue, Alpha, and Proximity
Proximity Sensor Range: 1cm - 10cm
Mounting Holes: 2 x M3 Holes on a 32mm pitch
Dimensions: 41.7mm x 17mm x 15mm
Magnetic Limit Switch
The REV Robotics Magnetic Limit Switch is a three-sided active-low digital hall effect switch with three internal hall effect elements located on the top and sides of the sensor. The three elements are connected in parallel so that any one of them will trigger the sensor.
Hall effect sensors detect the presence of magnetic fields. The REV Magnetic Limit Switch is an omnipolar momentary switch meaning it will trigger when there is sufficient field strength of either magnetic pole (north or south) detected.
See our sample code for the REV Magnetic Limit Switch here.
Specifications:
Sensor Type: Digital, Active-low
Voltage Range: 3.3V - 5.0V
Signal Pinout: n & n+1
Magnetic Polarity: Omnipolar (both north & south)
Typical Trigger Distances*
Top: 10mm
Side: 5mm
Typical Hysteresis*: 5mm
Typical Included Magnet Strength: 4300G (0.43T) *Using the included magnet.
Touch Sensor
The touch sensor is best used for user input, but can also be used as a limit switch.
See our sample code for the REV Touch Sensor here.
Configuration:
The REV Touch Sensor is a digital sensor that is wired to the N+1 channel on our standard 4-pin JST PH connector. In other words, the REV Expansion Hub digital ports are grouped with two input/output channels per port: 0-1, 2-3, 4-5, 6-7. In general we refer to each channel as N and N+1. When pressed, the touch sensor pulls the digital channel low from its default high state.
Through Bore Motor Encoder
The REV Through Bore Encoder is specifically designed with the end user in mind, allowing teams to place sensors in the locations closest to the rotation that they wish to measure. This rotary sensor measures both relative and absolute position through its ABI quadrature output and its absolute position pulse output. Mounting an encoder has never been easier with a 1/2in Hex Through Bore paired with the molded mounting holes which allow users to quickly place this encoder on the object they want to measure. Using one of the included inserts allows for the 1/2in hex to convert to 3/8in hex, 5mm hex, or 1/4in round for additional flexibility.
See our sample code for the REV Through Bore Motor Encoder here.
Specifications:
Input Voltage: 3.3V - 5.0V
Logic Level: 3.3V (5V tolerant)
Incremental Output:
Quadrature Resolution: 2048 Cycles per Revolution (8192 Counts per Revolution)
Index Pulse Width: 90°e
Index Pulse Frequency: Once per Revolution
Absolute Pulse Output (Duty Cycle):
Output Period: 1025μs
Output Frequency: 975.6Hz
Minimum Pulse (0°): 1μs
Maximum Pulse (360°): 1024μs
Pulse Resolution: 10-bit
Connector: JST-PH 6-pin
Mounting Holes: #10 Clearance
Maximum Rotation Speed: 10000 RPM
Weight(s):
1/2in Hex (default): 23.0g (0.05lbs)
3/8in Hex: 23.5g (0.051lbs)
5mm Hex: 24.0g (0.052lbs)
1/4in Round: 24.0g (0.052lbs)