My 3D Printed Robot sucked... so I made an UNBEATABLE one!

Summary

In this video, the creator discusses the redesign and rebuild of a 3D-printed ant weight combat robot. After a disappointing performance at a recent competition, the video takes viewers through the process of improving the robot's design. Key updates include a four-bar linkage lifting arm, improved traction with custom mini tank treads, and enhanced control with a more reliable ESC. The creator also shares tips on using Fusion 360 for 3D modeling and manufacturing, ultimately making the robot more efficient, controllable, and ready for future competitions.

Takeaways

• 😀 The video focuses on redesigning a 3D printed ant weight robot for better performance in a combat robot competition.
• 😀 The previous design failed due to poor motor control, weight distribution, and insufficient ESC (Electronic Speed Controller) features like motor braking.
• 😀 The new design incorporates a four-bar linkage mechanism for a lifting arm, inspired by the Biohazard robot from BattleBots.
• 😀 Autodesk Fusion 360 is highlighted as a powerful tool for 3D modeling, CAD, CAM, and simulation, aiding in the design and manufacturing process.
• 😀 The new robot aims to combine high pushing power, good control, and a lifting mechanism for effective opponent manipulation in competitions.
• 😀 A key part of the new design is the use of high-traction silicone charity wristbands as miniature tank treads, offering flexibility and grip.
• 😀 The chassis was redesigned to be lighter and more durable, with design history in Fusion 360 enabling easy adjustments for weight and strength.
• 😀 Crowned pulleys were used in the drive system to prevent the tank tread belts from slipping off, a technique dating back to the industrial revolution.
• 😀 The robot now uses small gear motors with a 50:1 reduction for better control and less risk of spinning out of control.
• 😀 The robot is ready for competition, with the design files shared for free, and the creator recommends Fusion 360 for similar DIY projects.

Q & A

Why did the redesign of the robot perform poorly in the Adelaide Robot Havoc event?

The redesign performed poorly due to the heavy gear motors used, which caused the robot to be top-heavy. This led to issues with balance, making the robot wheelie constantly. Additionally, the low-budget speed controller lacked motor braking, making the robot difficult to control, especially with the lighter chassis.

What was the issue with the original robot's chassis?

The original robot's chassis was overweight for the ant weight class, which had a maximum weight limit of 150 grams. The PLA plastic used in the robot's construction was quite dense, causing it to exceed the weight limit. To fix this, the chassis was redesigned with thinner walls and a smaller front wedge.

How did the gear motors impact the robot’s performance?

The oversized gear motors were chosen to provide plenty of pushing power. However, they were so heavy that the weight had to be reduced in other areas, particularly the chassis. This imbalance led to the robot flipping over frequently and made it difficult to control due to a lack of braking functionality in the speed controller.

What design change was implemented to improve the robot’s control?

The new design focused on achieving better control with a low-profile four-wheel drive platform. It also featured a four-bar lifting mechanism driven by a metal gear servo. This setup aimed to improve stability, traction, and control while still being able to push opponents into the pit.

What inspired the design of the new robot's lifting arm?

The design of the new robot's lifting arm was inspired by the biohazard robot, a popular battle bot known for its low-profile design and effective lifting arm. The lifting arm uses a four-bar linkage system to convert rotary motion from the servo into a lifting action, similar to how biohazard’s arm worked.

How did the designer experiment with the four-bar linkage in Fusion 360?

The designer used Fusion 360's sketch workspace to experiment with different lengths and fixed points to adjust the four-bar linkage. This allowed for rapid prototyping and fine-tuning of the arm's motion before committing to the full assembly.

What materials were used for the components in the new design?

The components were primarily made from PLA Plus, which is tough enough for the application and easy to print. The four-bar linkage was assembled with wooden dowels for most joints, while wire was used for specific areas due to size limitations.

What innovation did the designer use for the robot’s traction?

The designer used charity wristbands as high-traction tank treads. These wristbands are made of flexible silicon, providing just enough stretch to grip the wheel hubs securely. This creative use of material helped provide better traction and control during combat.

How does the crowned pulley system help keep the belt in place?

The crowned pulley system uses a slight taper from the center to the edge of the pulley. This creates higher tension in the middle of the belt, which causes the belt to form an arc and self-center, preventing it from slipping off during rotation.

What changes were made to the robot's speed controller to improve performance?

The designer switched to a dual ESC (electronic speed controller) from Bot Bits, which includes motor braking, a feature that was missing in the previous budget ESC. This new ESC provides better control and handling, especially in a competitive environment.