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IR Sensor Array

Introduction

Specifications

Item Specifications
Weight 18g
Resolution 10bit(1,024)
Operation Temperature -5°C ~ +85°C
Voltage 7 ~ 15V (Recommended Voltage 11.1V)
Maximum Current 100mA
Command Signal Digital Packet
Protocol Type Half duplex Asynchronous Serial Communication (8bit,1stop,No Parity)
Link (Physical) TTL Level Multi Drop (daisy chain type Connector)
ID 254 ID (0~253)
Communication Speed 7,843bps ~ 1 Mbps
Feedback Input Voltage, IR Sensor Data x 7

How to Use

LED

The LEDs will be turned on if the sensor value is smaller than the sensor value for black color detection.

Black Color Detecting Calibration

The 3-Pin connector provides power; pressing the right button initializes the array with set threshold values. Press the button one more time the arrays halts auto-calibration and reverts back to set threshold values. Set values = (MAX_VALUE + 2 * MIN_VALUE) / 3; where MAX_VALUE is max value of sensors between the first and second button presses, and MIN_VALUE is the min value of sensors between the first and second button presses.

Reset

Press the left button once and the IR array will reset via the supplied 3Pin cable. Note that this will not change set black detection values.

Communications Protocol

IR array communications and communications-related hardware are shown here.

Control Table

Control Table consists of data regarding the current status and operation, which exists inside of Dynamixel. The user can control Dynamixel by changing data of Control Table via Instruction Packet.

EEPROM and RAM

Data in RAM area is reset to the initial value whenever the power is turned on while data in EEPROM area is kept once the value is set even if the power is turned off.

Address

It represents the location of data. To read from or write data to Control Table, the user should assign the correct address in the Instruction Packet.

Access

Dynamixel has two kinds of data: Read-only data, which is mainly used for sensing, and Read-and-Write data, which is used for driving.

Initial Value

In case of data in the EEPROM Area, the initial values on the right side of the below Control Table are the factory default settings. In case of data in the RAM Area, the initial values on the right side of the above Control Tables are the ones when the power is turned on.

Highest/Lowest Byte

In the Control table, some data share the same name, but they are attached with (L) or (H) at the end of each name to distinguish the address. This data requires 16bit, but it is divided into 8bit each for the addresses (low) and (high). These two addresses should be written with one Instruction Packet at the same time.

EEPROM Area

Address Data Name Description Access Initial Value
0(0x00) Model Number(L) Lowest Byte of Model Number R 74(0x4A)
1(0x01) Model Number(H) Highest Byte of Model Number R 1(0x01)
2(0x02) Firmware Version Firmware Version R -
3(0x03) ID DYNAMIXEL ID RW 100(0x64)
4(0x04) Baud Rate Communication Speed RW 1(0x0x)
5(0x05) Return Delay Time Response Delay Time RW 250(0xFA)
6(0x06) IR Threshold_L 1 Low Byte of IR Sensor #1 Threshold RW 16(0x10)
7(0x07) IR Threshold_H 1 High Byte of IR Sensor #1 Threshold RW 3(0x03)
8(0x08) IR Threshold_L 2 Low Byte of IR Sensor #2 Threshold RW 16(0x10)
9(0x09) IR Threshold_H 2 High Byte of IR Sensor #2 Threshold RW 3(0x03)
10(0x0A) IR Threshold_L 3 Low Byte of IR Sensor #3 Threshold RW 16(0x10)
11(0x0B) IR Threshold_H 3 High Byte of IR Sensor #3 Threshold RW 3(0x03)
12(0x0C) IR Threshold_L 4 Low Byte of IR Sensor #4 Threshold RW 16(0x10)
13(0x0D) IR Threshold_H 4 High Byte of IR Sensor #4 Threshold RW 3(0x03)
14(0x0E) IR Threshold_L 5 Low Byte of IR Sensor #5 Threshold RW 16(0x10)
15(0x0F) IR Threshold_H 5 High Byte of IR Sensor #5 Threshold RW 3(0x03)
16(0x10) Status Return Level Select Types of Status Return RW 2(0x02)
17(0x11) IR Threshold_L 6 Low Byte of IR Sensor #6 Threshold RW 16(0x10)
18(0x12) IR Threshold_H 6 High Byte of IR Sensor #6 Threshold RW 3(0x03)
20(0x14) IR Threshold_L 7 Low Byte of IR Sensor #7 Threshold RW 16(0x10)
21(0x15) IR Threshold_H 7 High Byte of IR Sensor #7 Threshold RW 3(0x03)

RAM Area

Address Data Name Description Access Initial Value
24(0x18) IR Data_L 1 Low Byte of IR Sensor #1 Value R -
25(0x19) IR Data_H 1 High Byte of IR Sensor #1 Value R -
26(0x1A) IR Data_L 2 Low Byte of IR Sensor #2 Value R -
27(0x1B) IR Data_H 2 High Byte of IR Sensor #2 Value R -
28(0x1C) IR Data_L 3 Low Byte of IR Sensor #3 Value R -
29(0x1D) IR Data_H 3 High Byte of IR Sensor #3 Value R -
30(0x1E) IR Data_L 4 Low Byte of IR Sensor #4 Value R -
31(0x1F) IR Data_H 4 High Byte of IR Sensor #4 Value R -
32(0x20) IR Data_L 5 Low Byte of IR Sensor #5 Value R -
33(0x21) IR Data_H 5 High Byte of IR Sensor #5 Value R -
34(0x22) IR Data_L 6 Low Byte of IR Sensor #6 Value R -
35(0x23) IR Data_H 6 High Byte of IR Sensor #6 Value R -
36(0x24) IR Data_L 7 Low Byte of IR Sensor #7 Value R -
37(0x25) IR Data_H 7 High Byte of IR Sensor #7 Value R -
40(0X28) Buzzer Data 0 Buzzer Notes RW -
41(0X29) Buzzer Data 1 Buzzer Ringing Time RW -
42(0x2A) Auto Threshold Set Automatic Object Detection Mode RW 0(0x00)
43(0x2B) IR Obstacle Detected IR Object Detection R -
44(0X2C) Registered Registration of Instruction RW 0(0X00)
47(0X2F) Lock Locking EEPROM RW 0(0X00)
48(0X30) IR Threshold_L 1 Low Byte of IR Sensor #1 Set Value RW 16(0x10)
49(0X31) IR Threshold_H 1 High Byte of IR Sensor #1 Set Value RW 3(0x03)
50(0X32) IR Threshold_L 2 Low Byte of IR Sensor #2 Set Value RW 16(0x10)
51(0X33) IR Threshold_H 2 High Byte of IR Sensor #2 Set Value RW 3(0x03)
52(0X34) IR Threshold_L 3 Low Byte of IR Sensor #3 Set Value RW 16(0x10)
53(0X35) IR Threshold_H 3 High Byte of IR Sensor #3 Set Value RW 3(0x03)
54(0X36) IR Threshold_L 4 Low Byte of IR Sensor #4 Set Value RW 16(0x10)
55(0X37) IR Threshold_H 4 High Byte of IR Sensor #4 Set Value RW 3(0x03)
56(0X38) IR Threshold_L 5 Low Byte of IR Sensor #5 Set Value RW 16(0x10)
57(0X39) IR Threshold_H 5 High Byte of IR Sensor #5 Set Value RW 3(0x03)
58(0X3A) IR Threshold_L 6 Low Byte of IR Sensor #6 Set Value RW 16(0x10)
59(0X3B) IR Threshold_H 6 High Byte of IR Sensor #6 Set Value RW 3(0x03)
60(0X3C) IR Threshold_L 7 Low Byte of IR Sensor #7 Set Value RW 16(0x10)
61(0X3D) IR Threshold_H 7 High Byte of IR Sensor #7 Set Value RW 3(0x03)

Control Table Description

Model Number (0)

This address stores model number of the DYNAMIXEL.

Firmware Version (2)

This address stores firmware version of the DYNAMIXEL.

ID (3)

The ID is a unique value in the network to identify each DYNAMIXEL with an Instruction Packet. 0~252 (0xFC) values can be used as an ID, and 254(0xFE) is occupied as a broadcast ID. The Broadcast ID(254, 0xFE) can send an Instruction Packet to all connected DYNAMIXELs simultaneously.

Note Please avoid using an identical ID for multiple DYNAMIXELs. You may face communication failure or may not be able to detect Dynamixels with an identical ID.

Baud Rate (4)

Baud Rate determines serial communication speed between a controller and DYNAMIXELs.

Value Baud Rate(bps) Margin of Error
1 1M 0.000%
3 500,000 0.000%
4 400,000 0.000%
7 250,000 0.000%
9 200,000 0.000%
16 115200 -2.124%
34(Default) 57600 0.794%
103 19200 -0.160%
207 9600 -0.160%

Note Less than 3% of the baud rate error margin will not affect to UART communication.

Return Delay Time (5)

After the DYNAMIXEL receives an Instruction Packet, it delays transmitting the Status Packet for Return Delay Time (9). For instance, if the Return Delay Time(9) is set to ‘10’, the Status Packet will be returned after 20[μsec] when the Instruction Packet is received.

Unit Value Range Description
2[μsec] 0 ~ 254 Default value ‘250’(500[μsec]), Maximum 508[μsec]

IR Detecting Threshold

Set black values for IR #1 ~ #7 This value is referred when detecting black and white color.

Values Black detection LED
Sensor value <= Threshold BIT 1 ON
Sensor value > set value BIT 0 OFF

When the sensor is powered, the value in EEPROM area will be used to initialize RAM area Threshold.

IR sensor values (1 ~ 7)

If infrared light is emitted with enough intensity it will reflect off walls, objects, the receiver will detect the reflected light. Light reflected from bright walls and objects will be read as a high value. Measured value range is 0-1,023.
Infrared light measured from walls, objects, textures may be output differently including a difference in measurement.

Buzzer Notes

A buzzer is installed in AX-S1, and simple beep sounds can be made. Total 52 musical notes can be made in Buzzer Notes, and various notes can be made because there are whole tones and halftones in each octave. The values of Buzzer Notes are assigned as the table below.

Buzzer Ringing Time

AX-S1 has a function to control the buzzer alarming time. It is possible to control by the unit of 0.1 second, and the minimum length is set to 0.3 seconds; the time can be extended up to maximum 5 seconds. That is, if 0~3 is entered, the buzzer rings for 0.3 seconds; if the value over 50 is entered, the buzzer rings only for 5 seconds regardless of the value. Moreover, if the ringing is finished, the buzzer ringing time is automatically initialized to ‘0’. There are 2 special buzzer ringing time functions for AX-S1. Firstly, the buzzer can be ringing without stopping. If 254 is entered in buzzer ringing time, and the number of desired musical notes is entered, the buzzer rings without stopping. To stop the ringing, ‘0’ is entered in buzzer ringing time. Secondly, the buzzer can play special melodies. If 255 is entered in buzzer ringing time, and then the value 0~26 is entered in buzzer notes, 27 melodies corresponding to each number can be played. If the ringing is finished, the buzzer ringing time is automatically initialized to ‘0’.

Automatic set black detection mode

Mode for automatic black detection set-up from start to finish paramenters. From ‘0’ to ‘1’ starts; from ‘1’ to ‘0’ finishes.

In the IR array if each IR sensor detected black value is lower than the set black valuethe values will be assigned as shown below; the LED turns on.

BIT Name
Bit 0 Black detection for IR sensor #1
Bit 1 Black detection for IR sensor #2
Bit 2 Black detection for IR sensor #3
Bit 3 Black detection for IR sensor #4
Bit 4 Black detection for IR sensor #5
Bit 5 Black detection for IR sensor #6
Bit 6 Black detection for IR sensor #7

Registered Instruction

Value Meaning
0 There are no commands transmitted by REG_WRITE
1 There are commands transmitted by REG_WRITE.

Note If ACTION command is executed, the value is changed into 0.

Lock

Value Meaning
0 EEPROM area can be modified.
1 EEPROM area cannot be modified.

Caution If Lock is set to 1, the power must be turned off and then turned on again to change into 0.