Twelve Dollar Robot Arm
A Facebook ad enticed me to order this $12 robot.
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Figure 1. Robot Arm Product Page
The photo and description seemed too good to be true. I should have read the details more carefully. From GearBest
Unboxing
The box arrived a few weeks later. Inside were some laser cut acrylic parts and a bag of screws. The box contained no servo motors, no Arduino, no electronic components, and no instructions.
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Figure 2. The Box of Robot Parts
The robot parts arrived in this tiny box.
When I looked again at the robot arm’s web page, I realized that I had ordered the bare-bones kit. For about twice as much money, I could have received a more complete kit with servos, an Arduino, and other useful components. Several product reviewers had made the same mistake. I found photos of the robot assembly process belowe the review comments.
Undaunted, I ordered four SG90 servos. They soon arrived.
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Figure 3. The Box of Servos
The four SG90 servos arrived in this tiny box with horns and screws.
Servos
Before assembling the robot, I wanted to learn more about the servos. I built a servo test stand to hold the four servos. I bought a servo tester to test the servos independently from the robot structure and to rotate them to their home positions.
This project will continue when I finish with the servos.