Design for Assembly
When travel by wheel reaches its limit, this little robot marches forward.
Our challenge was to create a robot small enough to fit inside of a shoe box and fast enough to walk 15 meters in less than two minutes.
- Motion Analysis
- Mechanism Design
- CAD Modeling
- 3D Printing
- Laser Cutting
Inspired by Nature
We studied how things walk in nature, how and when feet touch and leave the ground, and what patterns their motions follow. We then set out to mimic the behavior of a four-legged animal. We chose to give our robot four legs in order to achieve stability and make the assembly of the robot manageable.
We learned that the feet of four legged mammals, like the fox, travel along paths that are consistent. Since the motion is close to two-dimensional, we decided to design a four-bar linkage mechanism that could produce a similar motion. The links used for the legs were laser cut from acrylic plastic. (The proportions and output curve in the example to the right are not the ones used in our robot.)
We designed a power transmission system to power all four legs of the robot using a single motor. Part of the transmission included a gear train that reduced the speed of the output and elevated the torque. The gears for the transmission were laser cut from Delrin plastic.
We designed a lightweight chassis to secure the power supply, and motor in place. The core of the chassis was modeled using Creo Parametric CAD software and fabricated using a 3D printer. The outer walls of the body, which held the transmission shafts, were cut from wood.
- Designed gear train used in power transmission
- Designed and modeled chassis to secure motor and battery
- Led discussions about troubleshooting and solutions