Overview

I led the development of further iterations and testing of an 8'x8' high speed cable robot. The goal was to improve reliability and robustness in high speed and accurate movements, while increasing the size of the robot to the size of a shipping container. I led the team through every stage of the design process, keeping timelines, assigning tasks and reviewing designs to ensure quality and on-time deliverables. I also designed, manufactured, and assembled multiple components and mechanisms including winch plates and frame brackets.

Sentien’s current automated drone storage method requires a lengthy manipulation process after the drone lands, and isn’t capable of handling fixed wing drones.

Sentien’s suggested solution is a 2D cable robot the size of a shipping container that can accurately catch landing drones at high speeds.

Solution

Multiple mechanisms were simplified for increased reliability and reduced assembly difficulty. The robot frame was strengthened to hold up to high acceleration required to match the speed of landing fixed wing drones. Tensioners were designed to give some leeway in software control and prevent cable slack.

1D Prototype

The 1D prototype was built in order to test mechanism designs without a large assembly space. The winches and tensioners were tested together and the results were used to redesign and iterate.

FEA Validation was conducted on critical parts to ensure performance under worst case scenarios.

2D Prototype

After multiple design iterations and many days of manufacturing, the full 2D prototype of the 8'x8' cable robot was assembled and tested.

The tensioner was updated to include a tension sensor so that software-based tension control could be used in addition or instead of the mechanical tensioner.

The following videos are examples of various tests we conducted to check accuracy, speed, and reliability of the robot. Various motions were tested to ensure the robot could move the payload in a variety of ways. The winch mechanism was consistent throughout testing, and the tension systems successfully kept the payload stable. Initial testing showed that consistent, accurate movements were possible, but further testing is required to determine the long-term performance at high speeds.

High Speed Cable Robot Iteration 2