tailieunhanh - Build Your Own Combat Robot phần 3

Chúng ta không thể bắt đầu để cho bạn biết làm thế nào để thiết kế các "bot hoàn hảo," nhiều hơn chúng ta có thể thuyết phục bạn về những chiếc xe hoàn hảo, hoặc thiết lập truyền hình. Mọi người đều có ý tưởng riêng của họ về những gì tốt nhất. Có, chúng tôi tác giả có những thành kiến của chúng tôi và cảm thấy thoải mái với các kỹ thuật nhất định | UI L D IN G a robot requires that you make many decisions from the type of sensors you ll use to the color you ll paint it. Some of these decisions are trivial while others will make or break your robot. One decision in the make-or-break category is motors not just deciding which ones you ll use but determining how you ll optimize their performance. Most robots use the same class of motor the permanent magnet direct current PMDC motor. These commonly used motors are fairly low in cost and relatively easy to control. Other types of electric motors are available such as series-wound field DC motors stepper motors and alternating current AC motors but this book will discuss only PMDC -type motors. If you want to learn more about other types of motors consult your local library or the Internet for that information. Some combat robots use internal combustion motors but they are more commonly used to power weapons than to drive the robots largely because the internal combustion engine rotates only in one direction. If you are using an internal combustion engine to drive the robot your robot will require a transmission that can switch into reverse or use a hydraulic motor drive system. With electric motors however the direction of the robot can be reversed without a transmission. Many combat robots combine the two using electric motors for driving the robot system and internal combustion motors for driving the weapons. Another use for internal combustion engines is to drive a hydraulic pump that drives the robot and or operates the weapons. Since most robots use PMDC motors most of the discussion in this chapter will be focused on electric motors. At the end of this chapter is a short discussion of internal combustion engines. Electric Motor Basics Because the robot s speed pushing capability and power requirements are directly related to the motor performance one of the most important things to understand as you design your new robot is how the motors will perform. In .