Electromechanical Variator

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According to experts, in the near future, robotics is expected to transform farming entirely. In the world with the population of over 7 billion and increasing, farmers are under pressure to feed more people. Furthermore, the demand for healthier food has also grown and today's farmers are being pushed to make farming greener by using less pesticide. The problem is obvious and agriculture robotics must become an integral part of farming.As a hobbyist, I am fascinated by this particular industry (robotics), but I have noticed that torque and power parameters required for standard agricultural applications might be a real issue. Perhaps more than any other factor, the capacity of batteries has limited the infiltration of robotics into daily life. As computer processing and sensors have become cheaper and more powerful, batteries, woefully inefficient and slow to recharge, have slogged behind. Consequently, designing a more powerful robotic platform inevitably results in the exponentially increased overall price and weight of a product. While electric motors and batteries are great for small robots, many agricultural applications still await for improvements in battery technology.Contrary to the popular opinion and might seem like a step back, I believe that an IC engine has a potential to contribute towards agriculture robotics becoming a common phenomenon in farms. These engines are cheap considering their quality and widely available in the market. ICE technology is well-developed and has become efficient enough to make us careful about announcing its demise. Even from an ecological perspective, exhaust gas emitted from agricultural robots would be completely insignificant compared to car emissions. Moreover, battery disposal should be considered a bigger threat since accumulators contain hazardous substances.During my research, I have come across some of the products available on the market today that represent different ways of overcoming the battery problem by utilizing an IC engine, for instance, some remote control lawnmower models. In their mechanism, a gasoline engine spins a generator, which generates electricity and charges a relatively small battery. This system does not need additional batteries to power motors because of the continuous charging process. However, controversial opinions about the efficiency of such system suggested searching for other solutions. Another system that caught my attention is being utilized in most autonomous tractors, where vehicle movement is produced by a diesel engine through a differential and controlled with the help of a wheel or vehicle body rotation, based on a hydraulic system . Unfortunately, these systems are expensive and would result in an increased size and weight of a robotic platform. After realizing that, I was trying to find a system that would satisfy a tracked vehicle drive principle and it was the moment when I accidently entered the Baja SAE (Society of Automotive Engineers) challenge forum and saw the "Gaged" CVT model. It seemed space-economical, compact and a simple version of the infinitely variable transmission that could be easily modified to suit my needs. This CVT model encouraged me to redesign it into a prototype of an Electromechanical Variator. The working principle of my model is the same as of the original "Gaged" CVT, except that the drive pulley is attached to a moveable support (with the help of a pair of bearings), which would be moved back and forth via an actuator by electric motors. It is the most efficient electronically controlled infinitely variable transmission model that I could possibly think of. Due to my concern about making the manufacturing process as simple as possible, the design of my model is far from being perfect. Despite that, I have faced some problems with a clutch mechanism on the driven pulley of CVT. It would cost a fortune to manufacture parts of such complexity. The "Redesign" challenge reminded me about 3D printing, so I designed 3D printable parts (represented by green color) that could withstand a minimized load and optimize the overall cost of a prototype. All considered, I designed this model to introduce the idea of integrating ICE into agricultural robotic platforms. I understand that in the long run ICEs will probably go out and electric motors will going in, but it only encourages us to utilize their maximum potential. I also understand that this idea might be wrong, but I like to go through all the possibilities. P.S. I apologize for long description, could not resist giving some extra content.