DYNAMIXEL Motor 控制使用TTL

DYNAMIXEL Motor 

Dynamixel智能馬達是模組化形式，採用菊鏈多串接方式。這讓用戶可以輕鬆地更改和添加馬達關節，以獲得所需的扭力和自由度。

DYNAMIXEL Motor 有的是使用TTL,有的是使用RS485的訊號來做控制

而XL430-W250 則是使用TTL訊號來做控制

控制器 <----------TTL-------------> DYNAMIXEL Motor (XL430-W250 )

 TTL 共有3個Pin 

Data ---- 5V

VDD ---12V

GND 

所謂TTL 訊號控制可以看成是UART的半雙工模式，即出去(TX)和進來(RX) 都是走同一個TTL 的Data訊號

 UART TX -----------------------> TTL Data

 UART RX <----------------------- TTL Data

原廠的控制器如 OpenCM9.04, OpenCR, CM-150 and CM-200 等..

2.) 若要使用PC來控制 XL430-W250, PC端可以透過U2D2來達成

PC  <------UART over USB------ > U2D2  <-----TTL---->  XL430-W250,

PC可使用U2D2 來控制DYNAMIXEL 

關於U2D2

U2D2 is a small size USB communication converter that enables to control and operate DYNAMIXEL with PC.

 https://emanual.robotis.com/docs/en/parts/interface/u2d2/

Ports	Description
4Pin UART	Convert USB and UART
3Pin TTL Level	Connect to DYNAMIXEL with 3Pin TTL Level Communication
4Pin RS-485	Connect to DYNAMIXEL with 4Pin RS-485 Communication
Status LED	Display status of Power supply, TxD(Data write) and RxD(Data Read)
Micro-B USB	Connect to the PC with USB cable

關於 Dynamixel XL430-W250 Servo 

XL430-W250 servo 規格:

(TurtleBot3 Burger 漢堡款用之馬達)

– MCU 單晶片: ST Cortex-M3 (STM32F103C8 @ 72Mhz, 32Bit)
– 位置感測器: Contactless absolute encoder (12Bit, 360°)
– 馬達: Cored Motor
– 傳輸速度: 9,600 bps – 4.5 M bps
– 控制演算法: PID 控制
– 解析度: 0.088° (=360°/4,096)
– 操作模式:
• 速度控制
• 位置控制(0-360°)
• 延伸位置控制(多圈旋轉)
• PWM 控制(電壓控制)
– 重量: 57.2g
– 尺寸(W x D x H): 28.5 x 34 x 46.5 mm
– 齒輪比: 258.5 : 1
– 靜止轉距:
• 1.0N.m(9.0V, 1.0A)
• 1.4N.m(11.1V, 1.3A)
• 1.5N.m(12.0V, 1.4A)
– 無負載速度:
• 47 rpm(9.0V)
• 57 rpm(11.1V)
• 61 rpm(12.0V)
– 操作溫度: -5 ~ +72℃
– 工作電壓: 6.5V – 12.0V (建議 11.1V)
– 待機電流: 52 mA
– 指令訊號: Digital Packet
– 通訊介面:
• Half Duplex Asynchronous Serial Communication (8bit,1stop, No Parity)
– 連結(實體層):
• TTL Level Multidrop Bus (3-pin 串接式連結)
– 可用編號: 253 ID (0-252), 可串接
– 訊號回授: 位置, 速度, 負載, 即時 Tick, 軌跡, 溫度, 輸入電壓等
– 材質: 工程塑材
– 數據如有變更，請以原廠規格為準

出廠設定:

– ID = 1
– Baud Rate: 57,600bps (請依需要, 自行變更 ID 及 Baud Rate)

Control Table

The Control Table is a structure of data implemented in the device. Users can read a specific Data to get status of the device with Read Instruction Packets, and modify Data as well to control the device with WRITE Instruction Packets.

Control Table 內容有記錄在EEPROM區域及RAM區域

改寫EEPROM區域的值會一直記錄著, 而RAM區域馬達重置後值會回到初始值

修改EEPROM值, 要先將Torque Enable （位置64）設為０，才能修改

Control Table of EEPROM Area

Address	Size (Byte)	Data Name	Access	Default Value	Range	Unit
0	2	Model Number	R	1,060	-	-
2	4	Model Information	R	-	-	-
6	1	Firmware Version	R	-	-	-
7	1	ID	RW	1	0 ~ 253	-
8	1	Baud Rate	RW	1	0 ~ 7	-
9	1	Return Delay Time	RW	250	0 ~ 254	2 [μsec]
10	1	Drive Mode	RW	0	0 ~ 1	-
11	1	Operating Mode	RW	3	0 ~ 16	-
12	1	Secondary(Shadow) ID	RW	255	0 ~ 252	-
13	1	Protocol Type	RW	2	1 ~ 2	-
20	4	Homing Offset	RW	0	-1,044,479 ~ 1,044,479	1 [pulse]
24	4	Moving Threshold	RW	10	0 ~ 1,023	0.229 [rev/min]
31	1	Temperature Limit	RW	72	0 ~ 100	1 [°C]
32	2	Max Voltage Limit	RW	140	60 ~ 140	0.1 [V]
34	2	Min Voltage Limit	RW	60	60 ~ 140	0.1 [V]
36	2	PWM Limit	RW	885	0 ~ 885	0.113 [%]
44	4	Velocity Limit	RW	265	0 ~ 1,023	0.229 [rev/min]
48	4	Max Position Limit	RW	4,095	0 ~ 4,095	1 [pulse]
52	4	Min Position Limit	RW	0	0 ~ 4,095	1 [pulse]
63	1	Shutdown	RW	52	-	-

Control Table of RAM Area

Address	Size (Byte)	Data Name	Access	Default Value	Range	Unit
64	1	Torque Enable	RW	0	0 ~ 1	-
65	1	LED	RW	0	0 ~ 1	-
68	1	Status Return Level	RW	2	0 ~ 2	-
69	1	Registered Instruction	R	0	0 ~ 1	-
70	1	Hardware Error Status	R	0	-	-
76	2	Velocity I Gain	RW	1,000	0 ~ 16,383	-
78	2	Velocity P Gain	RW	100	0 ~ 16,383	-
80	2	Position D Gain	RW	4,000	0 ~ 16,383	-
82	2	Position I Gain	RW	0	0 ~ 16,383	-
84	2	Position P Gain	RW	640	0 ~ 16,383	-
88	2	Feedforward 2nd Gain	RW	0	0 ~ 16,383	-
90	2	Feedforward 1st Gain	RW	0	0 ~ 16,383	-
98	1	Bus Watchdog	RW	0	1 ~ 127	20 [msec]
100	2	Goal PWM	RW	-	-PWM Limit(36) ~ PWM Limit(36)	-
104	4	Goal Velocity	RW	-	-Velocity Limit(44) ~ Velocity Limit(44)	0.229 [rev/min]
108	4	Profile Acceleration	RW	0	0 ~ 32,767 0 ~ 32,737	214.577 [rev/min2] 1 [ms]
112	4	Profile Velocity	RW	0	0 ~ 32,767	0.229 [rev/min]
116	4	Goal Position	RW	-	Min Position Limit(52) ~ Max Position Limit(48)	1 [pulse]
120	2	Realtime Tick	R	-	0 ~ 32,767	1 [msec]
122	1	Moving	R	0	0 ~ 1	-
123	1	Moving Status	R	0	-	-
124	2	Present PWM	R	-	-	-
126	2	Present Load	R	-	-1,000 ~ 1,000	0.1 [%]
128	4	Present Velocity	R	-	-	0.229 [rev/min]
132	4	Present Position	R	-	-	1 [pulse]
136	4	Velocity Trajectory	R	-	-	0.229 [rev/min]
140	4	Position Trajectory	R	-	-	1 [pulse]
144	2	Present Input Voltage	R	-	-	0.1 [V]
146	1	Present Temperature	R	-	-	1 [°C]
168	2	Indirect Address 1	RW	224	64 ~ 661	-
170	2	Indirect Address 2	RW	225	64 ~ 661	-
172	2	Indirect Address 3	RW	226	64 ~ 661	-
…	…	…	…	…	-	-
218	2	Indirect Address 26	RW	249	64 ~ 661	-
220	2	Indirect Address 27	RW	250	64 ~ 661	-
222	2	Indirect Address 28	RW	251	64 ~ 661	-
224	1	Indirect Data 1	RW	0	0 ~ 255	-
225	1	Indirect Data 2	RW	0	0 ~ 255	-
226	1	Indirect Data 3	RW	0	0 ~ 255	-
…	…	…	…	…	-	-
249	1	Indirect Data 26	RW	0	0 ~ 255	-
250	1	Indirect Data 27	RW	0	0 ~ 255	-
251	1	Indirect Data 28	RW	0	0 ~ 255	-
578	2	Indirect Address 29	RW	634	64 ~ 661	-
580	2	Indirect Address 30	RW	635	64 ~ 661	-
582	2	Indirect Address 31	RW	636	64 ~ 661	-
…	…	…	…	…	-	-
628	2	Indirect Address 54	RW	659	64 ~ 661	-
630	2	Indirect Address 55	RW	660	64 ~ 661	-
632	2	Indirect Address 56	RW	661	64 ~ 661	-
634	1	Indirect Data 29	RW	0	0 ~ 255	-
635	1	Indirect Data 30	RW	0	0 ~ 255	-
636	1	Indirect Data 31	RW	0	0 ~ 255	-
…	…	…	…	…	-	-
659	1	Indirect Data 54	RW	0	0 ~ 255	-
660	1	Indirect Data 55	RW	0	0 ~ 255	-
661	1	Indirect Data 56	RW	0	0 ~ 255

如何使用

可以下載 R+ Manager 2.0 進行測試 (baudrate : 57600) 先使用工具操作

參考如下說明 

 http://blog.ittraining.com.tw/2020/08/dynamixel-motor-r-manager-20.html

*更多關於 R+ Manager 2.0 操作手冊 

控制協定

PC或控制器 <-----------Protocol 2.0------------> DYNAMIXEL Motor

兩邊之間的通訊協定 DYNAMIXEL Protocol 2.0

DYNAMIXEL SDK

DYNAMIXEL SDK supports various programming languages such as C, C++, C#, MATLAB, LabVIEW, Python and Java in order to help developing DYNAMIXEL control software. DYNAMIXEL SDK provides a bundle of functions/methods that can be used for operating DYNAMIXEL with protocols in the form of digital packet. DYNAMIXEL SDK is free to download from GitHub.

• ROBOTIS GitHub
• DYNAMIXEL SDK Manual

step1 下載DYNAMIXEL SDK
git clone https://github.com/ROBOTIS-GIT/DynamixelSDK.git

step 2 在rapsberry pi上安裝 DYNAMIXEL library libdxl_sbc_c.so
cd ~/DynamixelSDK/c/build/linux_sbc
make
sudo make install

step 3: 執行範例程式

~/DynamixelSDK/c/example/protocol2.0/read_write/linux_sbc

make 

./read_write

Note: 原始碼都要經過修改以配合使用的馬達型號

// Available Dynamixel model on this example : All models using Protocol 2.0
// This example is designed for using a Dynamixel PRO 54-200, and an USB2DYNAMIXEL.
// To use another Dynamixel model, such as X series, see their details in E-anual(emanual.robotis.com) and edit below "#define"d variables yourself.
// Be sure that Dynamixel PRO properties are already set as %% ID : 1 / Baudnum : 1 (Baudrate : 57600)

[References]

[1] https://emanual.robotis.com/docs/en/dxl/x/xl430-w250

[2] UART over TTL/RS232  http://blog.ittraining.com.tw/2022/10/uart-over-ttlrs232.html