Servo Circuits

Audio Detector switch

The following circuit can be used to detect those annoying piezo whistles that one can get from Radio Shack. For the Trinity Home Fire Fighting Contest, additional points accrue when the robot is started by a sound similar to a fire alarm. The actual whistle is specified as a particular Radio Shack piezo element, but the following circuit should be tunable across a wide range of pitches...

Servo Controller schematic

Servo motors have many uses in everything from robotics to puppetry to photography and beyond. These little motors can position their output shaft to any position on command and hold that position. Most servos have a range of motion to about 210 degrees and thankfully are very easy to control with a simple circuit such as the one presented here. Using just a 555 timer and a few support components this circuit can control a servo through it's full rotation based on the position of a pot. ..

Servo controller with 555

This circuit takes standard 0-10V control voltage (for example from analogue light controlling desk) and outputs a standard 1-2 ms RC servo motors control pulse. Power supply: 4-5V DC (same as for RC servo), consumes 15 mA of current. Control voltage range: 0-10V. Control input impedance: > 30 kohm. Output control signal suitable for RC servo motors: 1-2 ms pulse with and pulse repeat rate is around 80 Hz. Estimated component cost: less than 10 US dollars. Circuit performance: Protototypes have worked very well. Circuit is based on NE555 timer chip ..

Sun Light Chaser

With RFT illuminated, point R goes to 0 volt and LM runs. With LFT illuminated, point R goes to 0 volt and RM runs. With RFT and/or LFT not illuminated, points R/L go to +9 volt; P1 and P2 controls threshold point when RM/LM stop or start running. Remember to seperate FT1 and FT2 with a vertical cardboard wall in order to produce a shadow over the other FT whenthe first is illuminated by a lateral incident light...

Spider robot with PIC16F84

To get enough outputs from the PIC chip, a pair of 74HC164 shift registers was used. These need only two lines from the PIC (data & shift) to produce the twelve signal pulses for the servos. A single bit is shifted into the first shift register, then, after a specific delay, it is shifted to the next servo. The second shift register cascades off the first. This system can be extended for any number of servos. The idea of this design is that no power is needed when the legs are in the full down position. They also create a lot of extra leverage at the bottom of travel. This helps overcome friction as the leg is moving horizontally inward at this time. When the leg is raised, the velocity increases with height making it easy to raise the leg over an inch...

autopilot with rev 2.2 board

The servo driver is just simply two 4017 decade counters and lots of 0.1" headers. Only populate the A side headers; the B servo bank is optional and will require a few more header pieces. If you received 20 headers, you'll be short two of them. If you received 25 headers, go ahead and fill it up. You will have to cut the headers to get the 2 pin header for the power supply. There is a mistake (sorry!) in the 4017 power supply. You have to cut the two traces and solder on a jumper as shown. Zoom in to see the trace on the bottom that needs to be cut. The corresponding trace on the top also has to be cut. Zoom in on the next image to see the one to cut on top. Be sure that they are both fully severed; otherwise you will short the power supply and things won't work...

Servo motor Tester with PIC12F675

This is a simple servo tester which will comprehensively test the capabilities of almost any modern servo. It has two pushbuttons, CENTRE and SWEEP and a potentiometer which works as follows: CENTRE Does exactly that, centers the servo, afterwards the potentiometer determines position. SWEEP Sweeps the servo back and forth at a rate determined by the potentiometer setting. The PIC uses its internal timer to set up a constant frame duration of 20ms and the on/off ratio is set by the user...

DC servo motor driver with MC33030

DC Servo Motor Driver kit, designed using MC33030 IC, is the fastest and low cost way of getting your DC Servo Motor up and running...

This simple micro-control circuit controls a servo motor according to a 3-state switch. A servo motor acts as an actuator in 3 position. It has 3 wires, one for VCC, one for Ground and another one for position control. The last signal is a single pulse with variable width. The pulse width can vary between 1 and 2 mSec. An 1 mSec pulse width turns the motor axis in -45 degrees position...

No Description available...

Realistic flap and landing gear actuation. This circuit slows the speed of a conventional proportional servo. It regulates the time required for full servo rotation from 1 to 10 seconds without any reduction in the servo`s torque, and every servo position is possible (proportional)...

The controller is a 16F84 (not important as long as the PIC has 8 pins free and interrupt capability) that uses two lines for serial control. One for serial input and one for DTR/CTS (pin 8 is CTS on a 9 pin connector if you are hooking to a PC). It will take back-to-back updates and doesn`t have jitter...

I volunteered to turn a friend of mine`s Warhammer 40K Imperial Rhino personel carrier into a remote controlled item. Little did I understand the undertaking that I had agreed on! My requirements for this project were that the transmitter and receiver had to be a single chip design, done all in software. I succeeded. The receiver chip uses a Panasonic 4602 38KHz receiver and that`s it for external components. It has the serial input (GP3) , two RC hobby servo outputs (GP0/GP1) and three digital outputs (GP2,4,5). Here is the code for the receiver chip...

This Robot is still being constucted so if you have any ideas please send them to me. I would apreciate if those people who keep sending me e-mails for me to send you my project schematics, look at the "Schematics page" located to your left on the menu. I dont have anymore schematics for the time being.Also is there anybody who knows how to controll a servo?..

The interface uses a PIC16F876 microcontroller and not much else. It performs channel mixing, current limiting, and noise rejection. Push the stick forward, both motors move forward, move the stick to the left and the robot moves left. It makes the robot very driveable. You can use a wheel transmitter meant for cars to control it, in other words, one channel is throttle(both forward and reverse), the other steering...