How to Use Raspberry Pi Model 3B to

Control Alpha 1 Pro

Version 1.0

Note: This article is a tutorial for novices to use Raspberry Pi to connect with

Alphal 1 Pro humanoid robot, which only teaches how to build the connection

via Bluetooth on board, and how to control the robot motions based on the

corresponding protocols. Assume that the readers are already familiar with the

basic operations of Alpha 1 Pro and Raspberry Pi, and has some knowledge of

programming, etc.

Update Time Author Version

2017/06/16 Nick, CUI Ning V1.0, original release

1. How to Control Alpha 1 Pro Robot

Generally, there are several ways to control Alphal 1 Pro:

Use the official PC software for motion editions. The PC software can be

downloaded from the link below:

http://www.cn.ubtrobot.com/product/aboutinfo4.html

However, only the motions could be edited through the PC software, which

has no opened interfaces for developers.

If you want to use Raspberry Pi or other controllers to communicate with

Alpha 1 Pro, the Bluetooth inside the Alpha 1 Pro should be used.

Download the communication protocol for bluetooth from this link:

http://www.cn.ubtrobot.com/product/aboutinfo4.html

There are also three ways to control Alpha 1 Pro robot via Bluetooth:

Use an additional USB-to-Bluetooth communication module plugged

into Raspberry Pi

Use the Bluetooth on Raspberry Pi directly

Open the cover of Alpha 1 Pro, bypass the Bluetooth module on the

controller PCB, and connect with Raspberry Pi’s UART port through

Wires.

In the following, we will introduce how to use the bluetooth on Raspberry Pi

to connect and control Alpha 1 Pro humanoid robot.

2. Motion Editions and Bluetooth

Communication Protocol

Although there are some commands in the Bluetooth protocol to control the

actions of Alpha 1 robot servo by servo, it is difficult to edit some complicated

motions through single servo motor control; therefore, if you want to create your

own actions, the official PC software is recommended. After creating and

editing, the action will be saved in the storage in the format of hts file. The name

of the action file can be listed through a unique Bluetooth command. Once the

action list got, you can use the action command to control the robot perform the

corresponding actions edited.

2.1 How to edit the actions with PRP programming

Step 1: Alpha 1 Pro is able to be connected with your PC via USB-to-mini USB

cable. Install the PC software on your computer, open it, register an account,

and login. (If you want to see the existed action files in the storage, click the

Synchronize button on the top menu and then click the turning your robot to the

U-disk mode icon on the bottom.)

Step 2: Get familiar with the programming interface. The picture of the robot

head in the top right corner shows the connect status between the PC and the

robot.

Step 3: Now we start to use PRP to edit the actions.

PRP, Pose Record Playback, is a programming method developed by UBTech

Robot. The principle of it is to divide the action sequence frame by frame, and

record all the servo angles in each frame, and then make the robot playback

the action sequence following the action frames recorded.

For example, let’s edit the action of swing arms:

Click the button of adding a new action frame

Click the button of recording the servo angles in the arms. Then the servos

in arms will be powered off, and move the arms to the target pose you want

to edit. Then click the button of recording the servo angles in the arms again.

Click the button of adding a new action frame again.

Click the playback button to perform the actions recorded.

2.2 Bluetooth Communication Protocol

Both parties to communicate with each other correctly and efficiently should

be based on a regulated protocol. According to the communication protocol

document downloaded from the official website of UBTech Robot, many

functions could be achieved.

Here list some main commands. Download a Serial Port Bluetooth App on

your Android mobile phone, connect with Alpha 1 Pro via bluetooth and send

the commands below to test it.

Acquisition of action list:

Transmit: FB BF 06 02 00 08 ED

Receive: [Note] please decode the action name according to the bluetooth

communication protocol

67 65 74 20 75 70 D0

48 61 70 70 79 20 42 69 72 74 68 64 61 79 EC

BA F3 CD CB (后退/move backwards)

D0 A1 C6 BB B9 FB (小苹果舞蹈/Dance with a music)

D7 F3 B3 F6 C8 AD

C4 BE C2 ED CD C0 B3 C7 BC C7

BD AD C4 CF 73 74 79 6C 65

D7 D4 CE D2 BD E9 C9 DC 2D BC D3 B3 A4 B0 E6

D7 D4 CE D2 BD E9 C9 DC

Execution of action:

Transmit example1: FB BF 09 03 BA F3 CD CB 51 ED （后退）

Transmit example2: FB BF 0B 03 D0 A1 C6 BB B9 FB B4 ED （小苹果）

Powering off of all the servos:

Transmit: FB BF 06 0C 00 12 ED

Controlling the actions of a servo:

FB BF 0A 22 10 57 0A 00 0A A7 ED 16 号舵机转到 87°位置（16 号舵机的角度转动范

围为 57°至 111°）/ Rotate the servo motor (ID=16) to the target position at 87°

Acquisition of robot status:

Transmit: FB BF 06 0A 00 10 ED

Receive: FB BF 07 0A 00 01 12 ED 声音状态/ Speaker

FB BF 07 0A 01 00 12 ED 播放状态/ Play

FB BF 07 0A 02 80 93 ED 音量 / Volume

FB BF 07 0A 03 01 15 ED 舵机灯状态 / Servo LEDs

FB BF 07 0A 04 01 16 ED TF 卡状态 / TF storage

Acquisition of the angles of a servo:

Transmit: FB BF 06 24 10 3A ED 16 号舵机

Receive: FB BF 07 24 10 6F AA ED 6F:111°

FB BF 07 24 10 57 92 ED 57: 87°

FB BF 07 24 10 3F 7A ED 3F: 63°

FB BF 07 24 10 39 74 ED 57°

There are still some other functional commands in the Bluetooth

Communication Protocol document, and you can test them if your project needs

to.

3. Bluetooth Configurations of

Raspberry Pi

3.1 Add SPP to your Raspberry Pi

The controller board of Alpha 1 Pro has a Bluetooth module, which supports

Serial Port Profile. Therefore, it is imperative to configure your Raspberry Pi to

be compatible with SPP.

Commands: nano /etc/systemd/system/dbus-org.bluez.service

Modify the two lines of codes to:

ExecStart=/usr/lib/bluetooth/bluetoothd -compat

ExecStartPost=/usr/bin/sdptool add SP

Check the Bluetooth Service:

Command: hciconfig

Please refer to the link below to configure the SPP service:

http://blog.csdn.net/wanyeye/article/details/52909869

3.2 Connect the Raspberry Pi with Alpha 1 Pro

Command: rfcomm bind hci0 <Alpha 1 pro bluetooth mac address>

(Note: don’t use “connect” command)

4. Example

Here is an example source code to control the Alpha 1 pro via Bluetooth:

After binding with the Bluetooth on Alpha 1 Pro, compile and link the c

program file test_spp_client, and then execute it. Alpha 1 Pro will receive the

command to dance with music.

#include <stdio.h>

#include <stdlib.h>

#include <unistd.h>

#include <fcntl.h>

int main()

{

int fd,ret,i;

char buf[]={0xfb,0xbf,0x06,0x01,0x00,0x07,0xed};

char buf_1[] = {0xfb,0xbf,0x06,0x02,0x00,0x08,0xed};

char buf_2[] =

{0xfb,0xbf,0x0b,0x03,0xD0,0xA1,0xC6,0xBB,0xB9,0xFB,0xB4,0xED};

char rbuf[99];

fd = open("/dev/rfcomm0", O_RDWR);

if(fd < 0){ printf("open dev/rfcomm error!\r\n");

return -1;}

//write(fd,buf_1,sizeof(buf_1));

//write(fd,buf_1,sizeof(buf_1));

write(fd,buf_2,sizeof(buf_2));

printf("write end!\r\n");

while(1){

ret = read(fd,rbuf,sizeof(rbuf));

printf("recv ret:%d\r\n",ret);

for(i=0; i<ret; i++)

printf("[%d]:%x ",i, rbuf[i]);

sleep(1);

}

close(fd);

}