# Operate MR-Buggy 3 using NavQPlus and FMURT6 ## Introduction This tutorial describes how to operate [MR-Buggy 3](https://nxp.gitbook.io/nxp-cup/mr-buggy3-developer-guide-2022/getting-started) with [Logitech Joystick](https://www.logitechg.com/en-in/products/gamepads/f310-gamepad.940-000112.html?searchclick=logi) using [NavQPlus](https://nxp.gitbook.io/8mpnavq/) and [FMURT6](https://www.nxp.com/part/RDDRONE-FMURT6#/). The [synapse](https://github.com/CogniPilot?q=synapse\&type=all\&language=\&sort=) packages from [CogniPilot](https://github.com/CogniPilot) are built on NavQPlus which will read input from the Joystick and send the appropriate commands to FMURT6 over ethernet. The [mrbuggy](https://github.com/CogniPilot/cerebri/tree/main/app/mrbuggy3) application in [CogniPilot/cerebri](https://github.com/CogniPilot/cerebri/tree/main) running on FMURT6 takes commands from NavQPlus and sends operation signals to MR-Buggy 3 servo and motor controller. ## Items Needed

S. No.	NAME	QUANTITY
1	RDDRONE-FMURT6	1
2	Pixhawk Debug Adapter	1
3	J-Link EDU Mini	1
4	JST SH 10-Pin Cable	1
5	USB-C (Male) to USB-A (Male) Cable	4
6	Micro-USB (Male) to USB-A (Male) Cable	1
7	.05" 10-Pin Ribbon Cable	1
8	MR-Buggy 3 Kit	1
9	Logitech G F310	1
10	USB-A (Female) to USB-C (Male) Adaptor	1
11	NavQPlus	1
12	Cat6a (Male) ix Industrial to RJ45 (Male) Ethernet Cable	1
13	USB-UART serial debugger	1
14	E3648A 100W Dual Output Power Supply	1
15	JST GH 1.25mm Pitch 2 Pin Cable (Female to Female)	1
16	JST GH 1.25mm Pitch 6 Pin Cable (Female to Female)	1

## Hardware Procedure

Block Diagram of the Complete Hardware Setup

Pixhawk Debug Adaptor and J-Link EDU Mini

#### Power Supply Setup 1. Press "Power" Button. 2. Press "Output On/Off" Button. 3. Select "Voltage" from "Voltage/Current" Button. 4. Set the Voltage to 7.4 V from the "Tuning Nob." 5. Connect the output wires to XT60 M1 on buggy.

## FMURT6 Software Procedure (on host machine) #### Prerequisites 1. Unrestricted network connection 2. [Ubuntu 22.04](https://releases.ubuntu.com/jammy/) on native machine 3. Setup ssh keys ``` sudo apt update sudo apt upgrade sudo apt install git ``` #### Software Setup ``` mkdir -p ~/git/cognipilot/ cd ~/git/cognipilot/ git clone git@github.com:CogniPilot/helmet.git cd helmet ./scripts/install.sh -f dream/mrbuggy3.yaml ``` {% hint style="info" %} Type "y" + "enter" when required. {% endhint %} ``` source ~/.bashrc source ~/.profile ``` #### Building and Flashing ``` cd ~/git/cognipilot/ws/cerebri/app/mrbuggy3 west build -b mimxrt1062_fmurt6 -p ``` {% hint style="info" %} Download and install Jlink from: {% endhint %} ``` west flash ``` {% hint style="warning" %} If you get an error with "west flash," make sure J-Link EDU Mini is directly connected to your machine. If that doesn't work then unplug and re-plug the FMURT6 board. {% endhint %} ## NavQPlus Software Procedure (on navq+ board) #### Prerequisites 1. [Ubuntu 22.04.3 Humble Image](https://github.com/rudislabs/navqplus-create3-images/releases/tag/v22.04.3) 2. Unrestricted network connection 3. Setup ssh keys {% hint style="info" %} NavQ+ requires internet connection for the following setup. If an ethernet connection is not available, connect the board to the native ubuntu machine via ethernet and [create a network bridge from wifi to ethernet on your machine](https://amigotechnotes.wordpress.com/2019/01/25/share-usb-tethering-to-wifi-and-ethernet-devices/). {% endhint %} #### Accessing Shell ``` minicom -D /dev/ -b 115200 ``` {% hint style="info" %} username=user password=user {% endhint %} #### Software Setup ``` sudo apt update sudo apt upgrade sudo apt install ros-humble-actuator-msgs mkdir -p ~/git/cognipilot/src cd ~/git/cognipilot/src git clone git@github.com:CogniPilot/synapse_ros.git git clone git@github.com:CogniPilot/synapse_msgs.git git clone git@github.com:CogniPilot/synapse_protobuf.git git clone git@github.com:CogniPilot/synapse_tinyframe.git cd ~/git/cognipilot colcon build --symlink-install ``` {% hint style="warning" %} Comment out both the interfaces listed in \~/CycloneDDSConfig.xml; {% endhint %} #### Network Setup ```` sudo vi ~/.net.sh ``` (Add the following lines in ~/.net.sh) #!/bin/bash sudo ethtool -s eth0 master-slave forced-slave sudo ifconfig eth0 192.0.2.2 netmask 255.255.255.0 ``` ```` {% code fullWidth="false" %} ``` echo "bash /home/$USER/.net.sh" >> ~/.bashrc source ~/.bashrc ``` {% endcode %} ## Running and Demonstration #### Execution on NavQPlus {% hint style="info" %} Since, ros2 commands block the shell, we will need two shells for the following. {% endhint %} ``` ros2 run joy joy_node --ros-args -r /joy:=/cerebri/in/joy cd ~/git/cognipilot/install source setup.bash ros2 launch synapse_ros synapse_ros.launch.py ``` {% hint style="warning" %} If the TCP connection fails, reset FMURT6. {% endhint %} #### Operation from Joystick

1. Set the Joystick to X-Input Mode (from the switch behind the controller). 2. Press the mode button such that the green light next to it is turned on. 3. Press green button A (0) to select manual mode. 4. Press start button (7) to arm in the selected mode. 5. Use vertical d-pad axis (1) for acceleration/reverse. 6. Use horizontal right-stick axis (3) for steering. 7. All controls: joy axes 1 is throttle, joy axes 3 is yaw/steering, button 7 is arm, button 6 is disarm, button 1 is mode manual, button 1 is mode auto, button 2 is mode cmd\_vel. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://nxp.gitbook.io/navqplus/mr-buggy3-demo/operate-mr-buggy-3-using-navqplus-and-fmurt6.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.