Meet the MeccaSpider: a spider robot for kids aged 10 and up that gets them familiar with technology and engineering concepts. It has 291 parts, including a brain module, IR sensor, motor modules, and batteries. You can control the robot with its buttons or through an app.
The MeccaSpider uses IR sensor to send movement and attack target. In guard mode, it tries to keep intruders out. Costs under $90 at this time.