Robotics seems to be at the forefront of every field these days – medicine, education and caster manufacturing to name a few. Even house cleaning is being reinvented by floor-cleaning robots. Despite the many applications, shapes and sizes, what almost all robots – even the famous R2-D2 – have in common is that they have to move. And that requires wheels and casters. In this issue of Wheels Revealed, we look at robots, wheels and casters.
The type of wheel to be used on a robot has a lot to do with the way it will be steered. There are two ways of doing that. The most common is skid steering. That’s when each wheel is attached to it’s own motor. By having one wheel propelled forward while the other is reversed, robots can be turned. It’s actually the method that is used to steer tanks and many tractors.
The other steering method uses a drive train, similar to what you would find in cars. In those cases, the criteria for wheel choice would be more about the surface and the environment. If the robot is travelling on wood, concrete or ceramic floors, tread material with a lot of grip is the answer. Rubber and polyurethane are ideal. Robots traveling on rugged or outdoor surfaces, will require varying degrees of tread.
There are complicated formulas that can be used to calculate the ideal wheel size for a robot. Essentially they combine the speed at which the robot will travel, with the weight it will carry and the incline, if any, it will traverse.
Not all wheels on robots are connected to motors or drive trains. Some are used to guide or stabilize the robot and in those cases, rigid or swivel casters are the best choice. A great example is robotic, computer guided chassis with top mounted carts used in hospitals to delivery food and linens to various locations. The devices have a number of drive wheels for propulsion and four Automated Guided Vehicle (AGV) casters with an auto align function.
Algood was proud to have built the casters that are being used in Canada’s first fully computerized hospital. In that case, the robotic cart used a specially constructed 6″ X 1-1/4″ stainless steel caster, equipped with our Envirothane™ wheels.
With all the amazing things that robots can do, it’s easy to take their wheels and casters for granted. But it’s also very clear that those wheels and casters are what’s necessary to keep robots rolling into the future of manufacturing… caster manufacturing.