> For the complete documentation index, see [llms.txt](https://drcl.mju.ac.kr/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://drcl.mju.ac.kr/research/project/mj-vesc/mjvesc-framework.md).

# MJ-VESCuino

{% hint style="info" %}
If you have any question on MJ-VESC, please leave a topic on 'Board' or send a email to <dongilc@mju.ac.kr>.&#x20;
{% endhint %}

## 1. What is MJ-VESC?

#### The MJ-VESC Project was launched to apply the VESC, which is commonly used in electric-skating board, to *"the Robotics area"*.&#x20;

#### The unique thing of MJ-VESC is stack-able design. The board form factor is Arduino Shield Type. So, it can be stacked on the Arduino.

<div align="center"><img src="/files/-LYqH4dgPHVFfbliFklL" alt="MJ-VESC ver0.1"></div>

![Stacked three MJ-VESCs with 3D printed Case.](/files/-LYqHwKfCEGJbuijVFQK)

![Stacked four MJ-VESCs on Arduino Due with 3D printed Case.](/files/-LYqJNSGoAIQA7MJXYSJ)

#### The hardware improvements from the existing VESC are as follows:

1. In **FOC** control, we provide **high torque** control even at **low speed**.&#x20;
2. **Position control** is possible at **Hall sensor** commutation with AB encoder (without index).
3. Hall & Encoder **Hybrid Commutation** for more precise position control.
4. More **accurate current control** by changing shunt resistor from 0.5mohm to 2mohm.
5. **Improved CAN** Communication Noise Filter using split terminal resistor and EMI filter.

#### The software improvements from the existing VESC are as follows:

1. High accuracy position control using "**DPS speed control**" (Degree Per Second).
2. VESC - **Arduino** high speed communication using **SPI communication**.
3. **Debugging terminal** using extra serial communication.

## 2. MJ-VESC Firmware Github Page

### 2.1. Firmware for MJ-VESC VER0.1

{% hint style="info" %}
The **MJ-VESC Firmware** version is based on **vesc bldc firmware 3.40** and compatible **VESC-TOOL** version is **0.95** at this moment.
{% endhint %}

{% embed url="<https://github.com/dongilc/bldc-mjvesc_v01_3.40>" %}

### 2.2. Original Firmware of VESC

{% embed url="<https://github.com/vedderb/bldc>" %}

### 2.3. VESC-TOOL 0.95

{% embed url="<https://github.com/vedderb/vesc_tool>" %}

## 3. ROS Control Framework for MJ-VESC

In this page, I will explain how to setup MJ-VESC when the high-level controller is based on **ROS** and communication method is **USB**.

1\. First, run VESC-TOOL (I assume that the motor setup of all the MJ-VESC is already finished)

```
./vesc_tool_0.95
```

Connect MJ-VESC ID=0.

```
Go to App Settings -> General -> APP to USE : Custom User App 
Go to App Settings -> General -> Send CAN Status : False.
```

2\. Connect MJ-VESC ID=1\~ using CAN-FORWARD (Setup all the other MJ-VESCs as below in case of ID>=1)

```
Go to App Settings -> General -> APP to USE : UART
Go to App Settings -> General -> Send CAN Status : True
```

The VESC-TOOL setup is finished.

3\. Download attached source code named 'vesc\_control\_ex1.zip'. You also need vesc library for ROS. Download 'vesc.zip' which is ros driver for MJ-VESC.

4\. Unzip and put those folders at your catkin workspace and then build. When you build, you may need dependencies as follows:

```
serial
ackermann-msgs
```

You can install above packages like this (when you use 'ros-melodic' then replace 'kinetic' to 'melodic').&#x20;

```
sudo apt-get install ros-kinetic-ackermann-msgs ros-kinetic-serial
```

5\. Run the ROS example using launch file below. Change argument 'port' depend on your condition.

```
roslaunch vesc_control_ex1 vesc_control_ex1_teleop.launch port:=/dev/ttyACM1
```

The main function of 'vesc\_control\_ex1\_node.cpp' is as below.

```
/*
 * Main Function
 * 
 */
int main(int argc, char **argv)            
{
  ros::init(argc, argv, "vesc_control_node");

  // loop freq
  int rate_hz = 50;	//hz

  // TeleopVesc Class
  const int num_of_vesc = VESC_ID_END+1;//4;
  TeleopVesc *teleop_vesc = new TeleopVesc(num_of_vesc);
  teleop_vesc->enable.data = false;

  // ROS Loop
  int cnt_lp = 0;
  ros::Rate loop_rate(rate_hz); //Hz
  ROS_INFO("Start Tele-operation");
  while (ros::ok())
  {
		teleop_vesc->enable.data = true;

		// read encoder data.
		//teleop_vesc->requestCustoms();
		//ROS_INFO("rps_0:%.2f(dps_0:%.2f), rad_0:%.2f", teleop_vesc->rps[0], teleop_vesc->rps[0]*RPS2DPS, teleop_vesc->rad[0]);
		//ROS_INFO("rps_1:%.2f(dps_1:%.2f), rad_1:%.2f", teleop_vesc->rps[1], teleop_vesc->rps[1]*RPS2DPS, teleop_vesc->rad[1]);
		//ROS_INFO("rps_2:%.2f(dps_2:%.2f), rad_2:%.2f", teleop_vesc->rps[2], teleop_vesc->rps[2]*RPS2DPS, teleop_vesc->rad[2]);
		//ROS_INFO("rps_3:%.2f(dps_3:%.2f), rad_3:%.2f", teleop_vesc->rps[3], teleop_vesc->rps[3]*RPS2DPS, teleop_vesc->rad[3]);

		// // current example (A)
		//teleop_vesc->current[0] = 4.0;
		//teleop_vesc->current[1] = 4.0;
		//teleop_vesc->current[2] = -1.0;
		//teleop_vesc->current[3] = 1.0;
		//teleop_vesc->setCurrentOut();

		// // brake example (A)
		//teleop_vesc->brake[0] = 10.0;
		//teleop_vesc->brake[1] = 10.0;
		//teleop_vesc->brake[2] = 5.0;
		//teleop_vesc->brake[3] = 8.0;
		//teleop_vesc->setBrakeOut();

		// // speed example (erpm = rev/min*polepair, polepair=Encoder Ratio@vesc_tool)
		//teleop_vesc->speed[0] = 0.//-(15000.0 - 5000.0);
		//teleop_vesc->speed[1] = 1000.//(15000.0 + 5000.0);
		//teleop_vesc->speed[2] = -1000.0;
		//teleop_vesc->speed[3] = 5000.0;
		//teleop_vesc->setSpeedOut();

		// // duty example (0.005~0.95)
		//teleop_vesc->duty[0] = 0.1;
		//teleop_vesc->duty[1] = 0.1;
		//teleop_vesc->duty[2] = 0.1;
		//teleop_vesc->duty[3] = 0.5;
		//teleop_vesc->setDutyCycleOut();

		// // position example (0~360 deg)
		//teleop_vesc->position[0] = 0.;
		//teleop_vesc->position[1] = 15.;
		//teleop_vesc->position[2] = 270.;
		//teleop_vesc->position[3] = -45.;
		//teleop_vesc->setPositionOut();

		// Custom example
		teleop_vesc->custom_cmd_type[0] = COMM_SET_DUTY;
		teleop_vesc->custom_cmd_value[0] = 0.6;
		teleop_vesc->custom_cmd_type[1] = COMM_SET_DPS;
		teleop_vesc->custom_cmd_value[1] = 1000.;
		//teleop_vesc->custom_cmd_type[2] = COMM_SET_DPS;
		//teleop_vesc->custom_cmd_value[2] = -1000.;
		//teleop_vesc->custom_cmd_type[3] = COMM_SET_DPS;
		//teleop_vesc->custom_cmd_value[3] = 1000.;
		//teleop_vesc->custom_cmd_type[1] = COMM_SET_DPS;
		//teleop_vesc->custom_cmd_value[1] = 0.;
		teleop_vesc->setCustomOut();

		ros::spinOnce();
		loop_rate.sleep();
  }

  return 0;
}
```

You can test 'SetCurrent', 'SetDutyCycle', 'SetSpeed', 'SetPosition', 'SetBrake', 'SetDPS' by un-commenting each functions. "COMM\_SET\_DPS" is only valid when you use 'teleop\_vesc->custom\_cmd\_type'.

{% hint style="info" %}
All the encoder data are stored at 'teleop\_vesc->rps\[id]' and 'teleop\_vesc->rad\[id]'. The 'rps' is rad/sec' and The 'rad' is Radian. You can easily use these variables at main function.
{% endhint %}

### Attachment

{% file src="/files/-LYqLpciwrCe2HfhBHEQ" %}
VESC ROS Driver
{% endfile %}

{% file src="/files/-LYqLslDC-JhKGCFUGaT" %}