15 | | * Arduino protoShield+Breadboard [http://www.gearbest.com/boards-shields/pp_236627.html GearBest $3.26-$5] |
16 | | * Arduino motorShield [http://www.gearbest.com/development-boards/pp_22494.html GearBest ~$4] |
17 | | * 4WD Robot chassis (w/motors, encoders, etc.) [http://www.gearbest.com/development-boards/pp_157852.html GearBest $17] |
18 | | * Ultrasonic Rangefinder [http://www.gearbest.com/development-boards/pp_58067.html GearBest ~$1.25-2.50] |
19 | | * Ultrasonic RF with Servo motor [http://www.gearbest.com/diy-parts-components/pp_236523.html GearBest ~$5] |
| 16 | * Arduino protoShield+Breadboard [https://www.aliexpress.com/item/32493176287.html AliExpress ~$1.40] |
| 17 | * Arduino motorShield [https://www.aliexpress.com/item/32340299184.html AliExpress $2.07] |
| 18 | * Nice robot tank-tread chassis [https://www.aliexpress.com/item/32879672132.html AliExpress ~$30] |
| 19 | * Ultrasonic Rangefinder [https://www.aliexpress.com/item/32823674854.html AliExpress 10 for $8.50] |
| 20 | * Ultrasonic RF with Servo motors and pan/tilt [https://www.aliexpress.com/item/32895464666.html AliExpress $4] |