The MAGNIFICENT 7 (Sensor and Module Kits) for Mindstorms/Technic
Most complete set of sensors and modules for LEGO Robotics Invention System - based robots. Some of them (like Night Vision, Solar CELL modules, the MAGNETIC Sensor and Touch Sensor kits) also work directly with any LEGO TEchnic motors - no need for the expensive RIS set.
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With only two Lego motors, some standard Technic parts and the Wireless Computer Controlled Remote COntrol System kit you can habe in only 1-2 hours a robotic platform running around controlled by your PC or by yourself using the keyboard. Or let the motors do automatic pet feeding, sun-following greenhouse, remote door locking, etc.COLOR CAMERA WITH SOUND - ALL WIRELESS for a mobile Lego robot operating the next door (:-)