Beam Climbing Robot
Beam Climbing Robot
ME104 Mechanical Systems Design
ME104 Mechanical Systems Design
Won the "Best Design Award: Best Performance". My team had the fastest bot, beating two other full classes of Mechanical Engineers.
Won the "Best Design Award: Best Performance". My team had the fastest bot, beating two other full classes of Mechanical Engineers.
Final Product
Final Product
The Design and Manufacturing Core classes for Stanford Mechanical Engineering conclude in ME104. The course is a compilation of coursework on mechanical systems design that concludes with a difficult class competition. The goal of the project is to carry a heavy off-axis load up an I-Beam as fast as possible. As you can see in the image below, the weight is in a very difficult and awkward location. This project was intentionally challenging and nearly half of the teams didn't complete a robot that could complete the challenge at any point during the quarter. My team was the first to complete the climb and the fastest to achieve it across sixty to eighty other mechanical engineering students.
The biggest challenge of this project was friction. The I-Beam was smooth aluminum and only ABS was allowed for the bots, you couldn't add any glue or rubber to increase traction. The only way to achieve the required friction was to optimize the wheel locations on the far side of the robot from the weight. One wheel was under the beam and one was on top very near the edge. If your wheels weren't far enough away or were too wide the normal force on the wheels wouldn't be enough to generate the required friction.
Intertwined into this challenge is tuning the wheel location size, gear ratio, and other factors to make the climb achievable with the provided electrical components. This required solving the above location problem symbolically, combining those equations with the electrical equations (also solved symbolically), and then putting all of that into MATLAB to find the optimal load cases. Here is some of the math as an example. This factored in the power curves of the motor and a myriad of other factors. This script and design allowed us to beat out all the competition.
Motor and gear options are provided. All other parts needed to be 3d printed on Ender 3 printers provided.
The Design and Manufacturing Core classes for Stanford Mechanical Engineering conclude in ME104. The course is a compilation of coursework on mechanical systems design that concludes with a difficult class competition. The goal of the project is to carry a heavy off-axis load up an I-Beam as fast as possible. As you can see in the image below, the weight is in a very difficult and awkward location. This project was intentionally challenging and nearly half of the teams didn't complete a robot that could complete the challenge at any point during the quarter. My team was the first to complete the climb and the fastest to achieve it across sixty to eighty other mechanical engineering students.
The biggest challenge of this project was friction. The I-Beam was smooth aluminum and only ABS was allowed for the bots, you couldn't add any glue or rubber to increase traction. The only way to achieve the required friction was to optimize the wheel locations on the far side of the robot from the weight. One wheel was under the beam and one was on top very near the edge. If your wheels weren't far enough away or were too wide the normal force on the wheels wouldn't be enough to generate the required friction.
Intertwined into this challenge is tuning the wheel location size, gear ratio, and other factors to make the climb achievable with the provided electrical components. This required solving the above location problem symbolically, combining those equations with the electrical equations (also solved symbolically), and then putting all of that into MATLAB to find the optimal load cases. Here is some of the math as an example. This factored in the power curves of the motor and a myriad of other factors. This script and design allowed us to beat out all the competition.
Motor and gear options are provided. All other parts needed to be 3d printed on Ender 3 printers provided.
All of these symbolic equations were plugged into a MATLAB script to solve for all possible successful configurations. We combed through the resultant five or six possible cases and selected the ideal ones based on project and physical limitations.
The project also contained limitations on the amount of allowable displacement of the weight. These limitations existed in all directions and fine-tuning the shape of the robot arm required lots of FEA analysis. This was especially challenging because the beam was at an angle. This meant that the loads were not perpendicular to the beam. Additionally, the weight is required to be held quite far from the beam. This meant there was a significant torque put on the robot's body and required wheels on the edge of the beam to counteract said torque in the plane of the beam's surface. An example of the FEA is shown below.
The weight must be held at the shown distance from the beam. You can see we used two vertical wheels, one big one on the top and under the right lip of the I-Beam. The two horizontal small rollers on the beam edges are also shown. Finally, you can see the connection point between the two halves of the bot. This was necessary due to the small print bed on our printers.
The weight must be held at the shown distance from the beam. You can see we used two vertical wheels, one big one on the top and under the right lip of the I-Beam. The two horizontal small rollers on the beam edges are also shown. Finally, you can see the connection point between the two halves of the bot. This was necessary due to the small print bed on our printers.
The horizontal smaller rollers in the left image are used to counteract the torque shown in the image. As you can see because of the weight placement off of a steep beam there is a torque on the body that must be adjusted for.
The horizontal smaller rollers in the left image are used to counteract the torque shown in the image. As you can see because of the weight placement off of a steep beam there is a torque on the body that must be adjusted for.
