APPROVED BY CHECKED BY DRAWN BY DESIGNED BY TITLEDRAWING NO. SYMBOL CORRECTED REASON PAGES DATE CORRECTORNO URG-Series Communication Protocol Specification (SCIP Version 2.0) - 1/15 DATE: OCT. 11, 2006 URG SeriesCommunication Protocol Specification SCIP-Version2.0 Kawata Kawata Maejima Mori Ｃ－４２－０３３２０Ｂ  X 3 1. Change of URL. 2. Added explanation about LED blinking. 3. Added detail explanation about MD/MS command due to bug fix from F/W version 3.1.04. 4. Baud Rate -> Bit Rate. 2, 8, 13Kawata PR532503/Aug./2007 X 6 X 5  Add explanation about Firmware update mode1. HAdded link to IROS paper.H 2. Notice on release of URG_Configure.exe. 3. Corrected mistakes in encoding example. 4. Added detail explanation about string characters. 2, 4, 5 Kawata PR520508/Dec./2006 5, 19 Kawata01/Nov./2006 PR5181TITLE DRAWING NO. URG-Series Communication Protocol Specification(SCIP Version 2.0) - 2/15 Ｃ－４２－０３３２０Ｂ URG-Series Communication Protocol Specification (SCIP Version2.0) ♦ Introduction ♦ URG-Series are laser scanning-sensors (SOKUKI sensor) developed for robotic applications*1. Its communication specifications are designed to comply with command system in SCIP ver2.0 and SCIP ver1.1 developed by sensor interface research group*2. Command systems in SCIP are the set of pre-defined characters that are used to communicate between host (computer) and sensor in order to perform different sensor tasks or settings. This specification explains the command system defined in SCIP ver2.0. To use SCIP ver2.0 the sensor must be updated with the compatible firmware (see the Table1 for the details). Firmware and updating tools can be downloaded form the company’s web site http://www.hokuyo-aut.jp/02sensor/07scanner/urg.html(See below of the page.).  Table 1 Firmware Version SCIP ver1.1 SCIP ver2.0 0.2.91a or earlier YES NO 3.0.00 YES YES *1 See our paper for details about the sensor. H. Kawata, W. Santosh, T. Mori, A. Ohya and S. Yuta, "Development of ultra-small lightweight optical range sensor system", IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS2005), pp.3277-3282, 2005-8, Edmonton *2 For detail, contact Intelligent Robot Lab. Univ. of Tsukuba: http://www.roboken.esys.tsukuba.ac.jp/ ♦ Switching to SCIP Ver2.0 ♦ Even if the sensor is SCIP Ver2.0 compatible it will always start in SCIP Ver1.1 by default. It should be switched to SCIP Ver2.0 by sending the following [SCIPver2.0 Changing Command] [SCIPVer2.0 Changing Command] (HOST → SENSOR) S C I P 2 . 0 LF (SENSOR → HOST) S C I P 2 . 0 LF Status LF LF z Status: 00 --- Changed to SCIPver2.0 successfully. NOTE１: Default setting causes sensor to always start in SCIP ver1.1 mode even if it was changed to SCIP ver2.0 earlier. However by using specific software “URG_Configurer.exe” it can be made to start in SCIP ver2.0 by default. This software has been released. To download this tool, access http://www.hokuyo-aut.jp/02sensor/07scanner/urg.html. NOTE２:  SCIP2.0 prescribes that sensor must turn off its laser till receiving commands which mean to turn on it. Therefore, the sensor’s LED blinks after switching to SCIP2.0 by this command.TITLE DRAWING NO. URG-Series Communication Protocol Specification(SCIP Version 2.0) - 3/15 Ｃ－４２－０３３２０Ｂ ♦ Interface ♦ Sensor is equipped with RS232C and USB for external interface. Communication between sensor and host can be established using any one of these devices. However, if host and sensor is connected with both the devices, USB connection will have priority. It is also possible to switch between USB and RS232C connection by connecting and disconnecting with host by the USB cable even when the sensor is operating. USB has Communication Device Class (CDC) standard with its settings similar to RS232C. Therefore programs written for RS232C can also be used for USB. RS232C and USB setting details are given below. RS232C Bit Rate :19.2Kbps(initial setting),57.6Kbps,115.2Kbps, 250Kbps, 500Kbps, 750 Kbps Parity :None Data Bit :8 Stop Bit :1 Flow Control :None USB Version :2.0 Speed :Full Speed (Windows: 9Mbps, Linux: 256 Kbps when using standard driver) Class :Communication Device Class Caution: Port should be opened only after the OS assigns it to the device. Access to the device from the application should be done only when the host-device configuration is complete and host recognizes the device.TITLE DRAWING NO. URG-Series Communication Protocol Specification(SCIP Version 2.0) - 4/15 Ｃ－４２－０３３２０Ｂ ♦ Measurement and Data Encoding ♦ Angular resolution of URG-series is 0.3515625° (360° /1024 step). Step numbers 0, 384 and 768 represents sensor angles -135°, 0° and +135°with sensor’s front axis (measurement reference) respectively (Figure 1). Sensor’s measurable range is 240° between step 44 and 725. Figure 1: Top View DEAD ZONEFRONT Step0 (-135°) Step768 (+135°)Step384 (0°) Step725Measurable Range Direction of Rotation Step44 Sensor outputs measurement data of each step from 44 to 725 (Figure 1). Minimum measurement is 20mm and maximum can be set to either 4095 or 5600mm. Measurement data are supplied to the host after encoding. Data are expressed in 12 bits and encoded to 2-characters in 4095mm mode. It is expressed in 18 bits and encoded to 3 characters in 5600mm mode. In order to reduce the data volume, 6-bits binary data are converted to 1-byte character codes. The encoding process is very simple where, the 12 or 18 bits data is separated into 6 bits each and 30H added to them. Decoding is reverse of encoding where 30H is subtracted form every 6 bits. And if data are 2-characters 12 bits are merged or 18 bits merged if they are 3-characters 2-Character Coding Example: 1234mm = 0100110100102 ↓ Separation (0100112,0100102) = (13H, 12H) ↓ Add 30H (43H, 42H) = (C, B) 3-Character Coding Example: 5432mm = 10101001110002 ↓ Separation (0000012, 0101002, 1110002) = (1h, 14h,38h) ↓ Add 30H (31h, 44h, 68h) = (1, D, h) TITLE DRAWING NO. URG-Series Communication Protocol Specification(SCIP Version 2.0) - 5/15 Ｃ－４２－０３３２０Ｂ ♦ Communication Format ♦ The basic communication format in SCIP system is shown below. Communication always starts from host side by sending pre-defined Command consisting of Command Symbol, Parameter and String