Find out how we made the Leo Rover mobile robot watertight.
Whether you’re a roboticist, a scientist or simply a hobbyist, you surely want your rover to be robust. Being watertight is always a plus too, especially when you operate your robot outside. You never know what might happen so it’d be best to have a rover about which you don’t have to worry when it gets wet. Let’s take a closer look at a Leo Rover and see what makes it watertight.
The original idea was that the rover would be able to drive even underwater. And that didn't work out. But hey, it’s the thought that counts, right? :) But back to the point. It started from the Scorpio rover – a Martian robot developed by a student association at Wrocław University of Science and Technology that some of us were members of. We noticed that although the whole idea of Scorpio was that it was a prototype of a Mars vehicle, in fact, it wasn’t a Martian rover, but an Earth one. After all, it was the Earth's conditions it had to withstand. There’s rain on our planet and when we prepared Scorpio for planetary rover competitions such as ERC and URC, we had to take into consideration that in case of not particularly heavy rain, the contest would still proceed. Thus, the robot had to be built in such a way to hold out against such challenges. At that time, our robot was already designed to be able to drive in the rain.
As we kept working on the robot, we realized that anything can happen, it doesn’t have to be limited to rain. The rover should be able to withstand anything you throw at it. You don’t want your mobile robot to break down just because you’ve had a bad day and spilled something on it, do you? And that’s the assumption we came up with – to make sure the rover would survive harsh conditions and you wouldn’t have to worry about it.
As the product developed, the concept of the rover being watertight also went on. So, as of now, we claim that a Leo Rover is weatherproof and it really is. You can drive it in the rain and don’t have to worry that after getting wet, your robot’s toast. Trust us, it can handle it.
All the rover’s elements that could be damaged by water are properly protected. For example, the metal part by the wheels is a tube that holds the wheel motor inside.
The tube’s job is to protect the motor against impacts and to seal it. It also serves as a mounting element for bearings. On one side, the tube has O-rings to seal the wiring assembly, and on the other side, there’s a lip seal that allows the motor shaft to rub against it all the time, but being sealed.
That’s for the mechanical assemblies. Then, all the cables are sealed as they go through the rover’s parts. For example, they come out of the wheel tube with rubber gaskets, and these enter the robot’s main electronics box – all joints are simply sealed with various rubber gaskets.
Also, the Leo Rover’s front camera has a cover. We decided to go with a GoPro glass which is sealed, and it additionally protects the camera’s lenses from being scratched.
When it comes to the battery, all plugs are also sealed. We use the WEIPU plugs that have the IP68 protection class.
At the top of a Leo Rover, there’s a miniUSB socket with a thread that allows you to seal everything. Provided that you use a dedicated plug (BULGIN PX0441), you can have a watertight USB connection to your external devices.
By default, we provide a USB cap along with the robot. With it, a Leo Rover is totally sealed.
The only issue that arises here is adding components to the robot. A Leo Rover itself is completely watertight but the same cannot be said about the add-ons we provide as these are mostly components from our suppliers and not from us. So, you have to keep this in mind when mounting additional elements on the vehicle.
Also, we need to point out that the Leo Rover’s construction is watertight but as a precaution against mishaps, not for default, constant use in water. The rover can handle rain, splash, or even wading in water with its wheels submerged and it can still work. But after an application like that, it needs to be properly taken care of. This may entail opening every component that might have been flooded to let it dry. It might also call for taking out some parts of the rover such as the wheel motors. In sum, the Leo Rover robotic platform is watertight but to a certain degree, we don’t recommend making adiver out of it.
If you don’t have your own Leo Rover yet and you’ve been wondering how we made it watertight, now you know all the ins and outs :)
And if there are other things concerning the Leo Rover’s design that you’re curious about, make sure to check out this article.