I wanted to build a device with articulated steering. The choice was a tractor with few accessories. The entire construction was planned to be made out of Mercur kit. I started from the rakes which I thought to be the most difficult one. But, after a while, I found out that the rakes are quite impossible to build from Merkur. The only solution was a fusion of Merkur and Lego Technic kit.
The tractor is built out of Merkur kit
The rear part is connected with the front one using an articulation. The rotation is done using a stronger Hitec servo. The drive is made up from original Mercur motor. All necessary peripherals are placed in the trunk together with the microcontroller. Tractor is also equipped with lights and xBee module on the trunk in order to communicate with the remote controller.Click the image to show it in higher resolution
I started the construction by rakes. Rakes have two arms that are lifted using two pistons powered by Lego motor. The motor is connected with the tractor using a socket in the rear part. The rotation of the rakes is transmitted to the output shaft of the tractor.
Each arm has its own wheel which can turn around freely. The entire construction has another wheel. Rakes are connected to the tractor using a thee points hitch.Click the image to show it in higher resolution
The next accessory was a tipper. I chose a four wheel version. The tipper can be tipped using a small piston and a motor. The tipper is further equipped with directional, rear and brake lights. The connection with the tractor is done using a shaft. The electricity is distributed from the socket in the rear part of the tractor.Click the image to show it in higher resolution
Another accessory was a rear mower. It consists of tree drums that are powered by tractor’s output shaft. The mower is lifted using large piston and motor with gears. I had to make the construction properly reinforced since its center of gravity is significantly out of the tree point hitch after its lifted.
I decided to build a tiller from the remaining parts of the Lego. Since I had one air piston left, I used to lift the lumps breaker part of the tiller.Click the image to show it in higher resolution
Source codesClick the label to show the source code
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