;)
Parts:
P1_____________22K Log. Potentiometer
R1_____________22K 1/4W Resistor
R2,R3_________100K 1/4W Resistors
R4_____________47K 1/4W Resistor
R5______________2K2 1/4W Resistor (See Notes)
R6______________6K8 1/4W Resistor
R7_____________22K 1/2W Carbon or Cermet Trimmer
R8______________2K7 1/4W Resistor
C1,C6_________100nF 63V Polyester or Ceramic Capacitors
C2,C3__________10µF 63V Electrolytic Capacitors
C4_____________22µF 25V Electrolytic Capacitor
C5_____________22nF 63V Polyester or Ceramic Capacitor
C7____________470µF 25V Electrolytic Capacitor
Q1____________BC547 45V 100mA NPN Transistor
IC1_________TDA7052 Audio power amplifier IC
SW1____________SPST miniature Switch
MIC____________Miniature electret microphone
SPKR___________8 Ohm Loudspeaker
Screened cable (See Text)
Comments:
This design allows to operate two intercom stations leaving the operator free of using his/her hands in some other occupation, thus avoiding the usual "push-to-talk" operation mode.
No complex changeover switching is required: the two units are connected together by means of a thin screened cable.
As both microphones and loudspeakers are always in operation, a special circuit is used to avoid that the loudspeaker output can be picked-up by the microphone enclosed in the same box, causing a very undesirable and loud "howl", i.e. the well known "Larsen effect".
A "Private" switch allows microphone muting, if required.
Circuit operation:
The circuit uses the TDA7052 audio power amplifier IC, capable of delivering about 1 Watt of output power at a supply voltage comprised in the 6 - 12V range.
The unusual feature of this design is the microphone amplifier Q1: its 180° phase-shifted audio output taken at the Collector and its in-phase output taken at the Emitter are mixed by the C3, C4, R7 and R8 network and R7 is trimmed until the two incoming signals almost cancel out. In this way, the loudspeaker will reproduce a very faint copy of the signals picked-up by the microphone.
At the same time, as both Collectors of the two intercom units are tied together, the 180° phase-shifted signal will pass to the audio amplifier of the second unit without attenuation, so it will be loudly reproduced by its loudspeaker.
The same operation will occur when speaking into the microphone of the second unit: if R7 will be correctly set, almost no output will be heard from its loudspeaker but a loud and clear reproduction will be heard at the first unit output.
Notes:
* The circuit is shown already doubled in the diagram. The two units can be built into two separate boxes and connected by a thin screened cable having the length desired.
* The cable screen is the negative ground path and the central wire is the signal path.
* The power supply can be a common wall-plug transformer-rectifier having a voltage output in the 6 - 12V dc range @ about 200mA.
* Enclosing the power supply in the box of one unit, the other unit can be easily fed by using a two-wire screened cable, its second wire becoming the positive dc path.
* To avoid a two-wire screened cable, each unit may have its own separate power supply.
* Please note that R5 is the only part of the circuit that must not be doubled.
* Closing SW1 prevents signal transmission only, not reception.
* To setup the circuit, rotate the volume control (P1) of the first unit near its maximum and speak into the microphone. Adjust Trimmer R7 until your voice becomes almost inaudible when reproduced by the loudspeaker of the same unit.
* Do the same as above with the second unit.
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( 3 / 250 )遇到障碍物时,先停下,再往后倒几步,,左转一会儿,,再往前走,若走不通,再停下,往后退,,总能转出去的.
下面要做的就是语音识别了...正在研究这个软件...不久,,就能派上用场..
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( 3 / 302 );)
原图LINK在此
http://mars.jpl.nasa.gov/spotlight/imag ... browse.jpg
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( 3 / 335 )电机转的时候有电噪声,经查,是电机的驱动部分的地线和控制部分的地线绞在了一起..分开后,就没有了.
准确地说是减少了,,CPU不受干扰.
耳朵的分辨范围是4CM-4M,,准确率还成.机器人可以避开障碍物. 但避开的还不是很好.现在只是简单的动作..看到障碍物就左转..应该弄的复杂一点,无论什么情况下,都能进退自如..
只是还没有传感器能知道机器人自己的位置..比如想右转90度,,前进走1米,,再左转90度..
小蛮呢? 有啥子办法?
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( 3 / 328 )今天拿到了超声波距离传感器．．
;)
这样小猪八就能听见前面东西的远近了，，不会装上．．墙啊什么的．．
这超声波其实很简单，里面有一个小芯片，，发送４０KHz的超声,,然后再接受它的反射波,,其时间差乘上声速,,就是距离..
因没有发送和接受的小东西卖,,只好买整个产品了..
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( 3 / 326 )应该加两个，前面放一个，后面放一个，就可以避开障碍物了．
给机器人起名叫小猪八．
小猪八的机动性能超强，前进倒退，转弯３６０度非常地灵活．比方向盘控制要快多了．
还要再给它加上超强的猪脑子，，可以语音识别，能听话了．．
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( 3 / 364 );)
双电机控制,前进,转向,后退等.
两电机速度有差别的时候,就会转弯,,一样的话,就走直线.
因两个电机,需要两个PWM口,而选的小CPU只有一个硬件PWM口,另外一个要用中断来仿真,时间上来不及,,下次换个CPU.
以后弄个超级4轮驱动,一个轮子一个电机.其机动性会非常地高,,躲闪腾挪,,踢足球正合适..
准备在上面加个ARM9的板子,说话控制它,,再给它装一些MP3的歌..
走哪儿,,它跟着唱到哪儿..
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( 3.1 / 377 )这两天网上转了转, 机器人的板子很多都用I2C做为接口,这个东西,不好用啊.
以前用过I2C, 太容易坏了, 静电保护很差, 而且还需要电平匹配.不是很好的东西.
建议用CAN BUS,速度快,安全,有静电保护,且可传的很远. 只是成本高一些. 很多CPU I2C
都是内含的.
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( 2.9 / 371 )小电机是３Ｖ的玩具电机．可ＭＯＳ管的－２＜ＶＧＳ＜－４．
不得已，用５Ｖ的电源．
ＰＷＭ控制电机转速，可电机稍微一转快，ＣＰＵ就不工作了．给电机的两端加上陶瓷电容，也不成，又加了个铝电容，还是不成．其中一端接上电机外壳，效果好了点，最后两端串上小电感，ＣＰＵ工作才正常了．
这些电容电感都是从玩具小电机上拆的．
只是不明白，这电感为嘛能弄掉干扰？
可到这里讨论
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( 2.9 / 379 )想让那个机器人干点活,擦个地,剪个草什么的,不用遥控器控制,
可如何能让它自己走直线呢?
需要什么传感器?
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