Introduction to Rover

This article describes the main components of a Rover system, including the ground vehicle, autopilot hardware, and the software/firmware.

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Rover Components

While it is is possible to build a vehicle with Rover from scratch we highly recommend starting from an existing RC vehicle (this comes with a frame, escs and power supply). You will need to add the autopilot, GPS, and possibly some other hardware. Most importantly you will need to obtain an RC Transmitter that has spare channels needed for autopilot mode control and learning.

If you want a slow skid steering rover the WildThumper varieties are very popular. If you want a standard car then any 1/10 scale RC car is fine. We prefer 1/10 scale as its large enough to easily work on and fit any gear like companion computers etc. The 1/16 or 1/18 scale vehicles you have to squeeze everything on but as you can see from the photos in this wiki its certainly do-able. We tend towards 2WD instead of 4WD as well just because we get slightly longer battery life (fewer mechanical losses) and the car is less complicated. But if your looking to go on the dirt fast and corner hard then 4WD is the go. We also prefer vehicles with brushless motors and no RC - the RC units that come with most ready-to-run RC cars don’t have the spare channel needed for autopilot mode control and learning.

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Autopilot Hardware

Pixhawk is highly recommended for general use.

Developers creating robot vision applications should consider using a separate Companion Computer, or a Linux based autopilot board (e.g. NAVIO+ or Erle-Brain) which is capable of running both Rover and the image processing code.

For more options, see the topic Choosing a Flight Controller.

Note

You will need at least four female-to-female servo extension cables to connect the autopilot to your RC receiver (choose length to suit)

4+ channel RC transmitter and receiver

You’ll need a radio control transmitter to manually control your Rover and to activate its control modes. You can use any RC transmitter/receiver system with at least 4 channels.

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Don’t get one designed for cars (with a steering wheel and throttle trigger); we won’t be driving the Rover manually much at all. Ideally, it will have at least two toggles switches, and one of those switches will have three positions. If you’re on a budget, the Turnigy 9x ($54) is a popular choice. If you’d like better quality, we like the Taranis FrSky Reciever.

Some other options are discussed in the topic Compatible RC Transmitter and Receiver Systems (Pixhawk/PX4).

GPS module

Your Rover will require a GPS module. The recommended module is 3DR UBlox GPS + Compass Module which also includes a compass. You can check out other GPS solutions here.

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LiPo batteries and charger

You’ll also need batteries and a charger. Almost any 2S (7.2v) LiPo under 2600 mAh will do, but the recommend one for the above buggy is this one. A simple LiPo charger like this one will work fine.

Optional hardware

Telemetry Radio

A telemetry radio allows your Rover to communicate with your ground station remotely using the MAVLink protocol. This allows you to interact with your missions in real time and receive streaming data from your vehicle’s cameras and other components. This adds considerable convenience to your missions!

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Sonar/IR Sensors

Sonar/IR sensors are recommended for obstacle avoidance.

Ready to Use Rovers

At time of writing, the only Ready-to-Run (RTR) Rover is Erle-Rover.

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Erle-Rover: Ready to Use Rover from Erle-Robotics

This RTR Rover contains all the needed components for getting started: the frame, Erle-Brain Linux autopilot, 4 Channels 2.4Ghz RC, Power Module (to power up the autopilot), NIMH battery and charger.

Note

This Rover uses a powerful Linux autopilot that can run more computationally intensive operations than a traditional autopilot (like Pixhawk).

Ground Control Station

The (free and open source) Mission Planner is required if you’re going to be loading new versions of Rover onto the autopilot controller, and for first-time tuning and calibration. It runs on a PC and can also be used for planning missions.

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Once your Rover is configured, you may find it more convenient to choose a different ground station - running on the tablet, phone or computer of your choice. The main options are discussed in the topic Choosing a Ground Station.

Note

This wiki exclusively uses Mission Planner as the reference GCS.