WT81B003-0202 (Ultrasonic long distance sensor) - Revision history

Michael: /* Some consideration about "AP_RangeFinder" library */

2017-08-20T13:27:43Z

‎Some consideration about "AP_RangeFinder" library

2017-08-20T13:26:12Z

‎Implement Sonar support into Pixhawk firmware

2017-08-16T16:10:05Z

2017-08-16T16:08:43Z

Add a rough TODO list to implement the Waytronic sonar in the pixhawk fw

2017-08-03T21:45:37Z

2017-08-03T21:42:35Z

Documented the sensor tests made

2017-08-03T21:32:54Z

Added prototyping script

2017-08-02T23:00:42Z

UART with raspberry

2017-07-29T09:45:29Z

Added some prosa for better understanding

2017-07-29T09:35:57Z

@@ Line 62: / Line 62: @@
 TODO:
 #Define a new RangeFinder driver type adding a member in the "RangeFinder_Type" enum. (RangeFinder.h)
-#Add the device in the "void RangeFinder::detect_instance(uint8_t instance)" method so it can be detected. (RangeFinder.cpp)
+#Add the support for the sonar in the "void RangeFinder::detect_instance(uint8_t instance)" method so it can be detected. (RangeFinder.cpp)
 #....(you tell me 師傅 (shifu))

@@ Line 58: / Line 58: @@
 =Implement Sonar support into Pixhawk firmware=
-In order to add the Waytronic sonar support in the Pixhawk fw we need to implement a new library class in the /ardupilot/libraries/ folder and integrate it in the "RangeFinder" class.
+In order to add the Waytronic sonar support in the Pixhawk fw we first need to implement a new class for our specific device (AP_RangeFinder_WayTronic18mSerial) in the /ardupilot/libraries/ folder then integrate it in the generic "RangeFinder" class.
 ==Some consideration about "AP_RangeFinder" library==
 TODO:

@@ Line 61: / Line 61: @@
 ==Some consideration about "AP_RangeFinder" library==
 TODO:
-#Define a new RangeFinder driver type adding a member in the "RangeFinder_Type" enum.
+#Define a new RangeFinder driver type adding a member in the "RangeFinder_Type" enum. (RangeFinder.h)
-#Add the device in the "void RangeFinder::detect_instance(uint8_t instance)" method so it can be detected.
+#Add the device in the "void RangeFinder::detect_instance(uint8_t instance)" method so it can be detected. (RangeFinder.cpp)
 #....(you tell me 師傅 (shifu))

@@ Line 56: / Line 56: @@
 * Stable state machine implementation with timeouts and failure mode
 * Full sensor frequency usage (~ 10Hz)
 = Datasheet =
 The original datasheet is in Chinese, the following version was translated with Google Translate:
 <pdf>File:WT81B003-0202-datasheet-google-translate-en.pdf</pdf>

@@ Line 9: / Line 9: @@
 To quickly see what the sensor transmits on the UART ports, we can use a raspberry pi and a python script. See [https://electrosome.com/uart-raspberry-pi-python/ Using UART on Raspberry PI]
-The wiring is simply the TX UART pin connected with the RX pin of the sensor and the TX of the sensor connected through a voltage divider (5K1, 10K) to the RX UART pin of the raspberry.
+The wiring is simply the TX UART pin connected with the RX pin of the sensor and the TX of the sensor connected through a voltage divider (5K1, 10K) to the RX UART pin of the raspberry. The raspberry was connected via Ethernet + SSH to the PC and printed the results on the terminal, so no keyboard + monitor needed.
 [[File:Raspberry-pi-2-gpio-pinout.png|thumb|GPIO Pinout]]

@@ Line 14: / Line 14: @@
 The following python script then does all the work easily. A test output can be '''1.26m 25.1°'''.
@@ Line 37: / Line 44: @@
 </syntaxhighlight>
 = Datasheet =

← Older revision		Revision as of 21:32, 3 August 2017
Line 8:		Line 8:

	To quickly see what the sensor transmits on the UART ports, we can use a raspberry pi and a python script. See [https://electrosome.com/uart-raspberry-pi-python/ Using UART on Raspberry PI]		To quickly see what the sensor transmits on the UART ports, we can use a raspberry pi and a python script. See [https://electrosome.com/uart-raspberry-pi-python/ Using UART on Raspberry PI]
		+
		+	The wiring is simply the TX UART pin connected with the RX pin of the sensor and the TX of the sensor connected through a voltage divider (5K1, 10K) to the RX UART pin of the raspberry.
		+
		+	[[File:Raspberry-pi-2-gpio-pinout.png\|thumb\|GPIO Pinout]]
		+
		+	The following python script then does all the work easily. A test output can be '''1.26m 25.1°'''.
		+
		+
		+	<syntaxhighlight lang="python" line>
		+	#!/usr/bin/env python
		+	# -- coding: utf-8 --
		+
		+	import serial
		+	import binascii
		+	from struct import *
		+
		+	ser = serial.Serial("/dev/ttyAMA0")
		+	ser.baudrate = 9600
		+
		+	ser.write("\0")
		+	output = ser.read(6)
		+	header, distance, temp, checksum = unpack(">cHhc", output)
		+
		+	#print(binascii.hexlify(output))
		+
		+	print("%.2fm, %.1f°" % (distance/1000.0, temp/10.0))
		+	ser.close()
		+
		+	</syntaxhighlight>

	= Datasheet =		= Datasheet =

@@ Line 4: / Line 4: @@
 Using an Arduino board equipped with an uart port it's possible to test the sonar performance.
 The sketch can be found at https://mega.nz/#F!Bo8jHabQ!kwxQR5jFZorFaOLdQKsTdw)
 = Datasheet =

← Older revision		Revision as of 09:35, 29 July 2017
Line 8:		Line 8:
	The original datasheet is in Chinese, the following version was translated with Google Translate:		The original datasheet is in Chinese, the following version was translated with Google Translate:

−	<pdf>~~File:~~File:WT81B003-0202-datasheet-google-translate-en.pdf</pdf>	+	<pdf>File:WT81B003-0202-datasheet-google-translate-en.pdf</pdf>