Description: The SparkFun Servo Trigger is a small robotics board that simplifies the control of hobby RC servo motors. When an external switch or logic signal changes state, the Servo Trigger is able to tell an attached servo motor to move from position A to position B. To use the Servo Trigger, you simply connect a hobby servo and a switch, then use the on-board potentiometers to adjust the start/stop positions and the transition time. You can use a hobby servos in your projects without having to do any programming!
The heart of the Servo Trigger is an Atmel ATTiny84 microcontroller, running a small program that implements the servo control features we are discussing here. On-board each Servo Trigger you will find three potentiometers, “A” sets the position the servo sits in while the switch is open, “B” sets the position the servo moves to when the switch is closed, and “T” sets the time it takes to get from A to B and back. Compared to a servo motor, the Servo Trigger board draws very little current, roughly 5 mA at 5V. Be sure to note that if you’re using the Servo Trigger to control your motor, the absolute maximum supply voltage that should be applied is 5.5 VDC. Additionally, the SparkFun Servo Trigger is designed to make it easy to daisy chain boards – you can simply connect the VCC and GND pads on adjacent boards to each other.
Note: Check out the Hookup Guide in the Documents section below for more advanced tips, configurations, and modes!
Note: This idea originally came from our friend in the Oakland area, CTP. If you see him, please give him a high-five for us.
Based on 7 ratings:
1 of 1 found this helpful:
Everything about this is excellent, except the limited range. I had some projects in mind that would utilize the full 180 range of a servo, so the fact that this limits this by HALF is a bit of a disappointment.
1 of 1 found this helpful:
It would be nice if the range was > 90° in my case the full 180° would have better for my application.
Hooked this up to the output from an IR sensor and it gave me great control of the two positions of the servo depending upon the presence or absence of the IR beam on the sensor. The pots are a great way to control the positions. Kudos!
If you are looking for a project to work on as someone new to electronics, or something that is fun to work on with kids, these are really great. No programming involved at all. A perfect way to get straight to building the mechanics with immediate results.
Hope the next version goes 180 degrees
I used this with a custom CNC pen plotter to control the pen up/ down movements. This board provides a lot of function in a small package, yes I said that. It was a great way to keep my project clean. I do recommend this product. To see my application visit https://www.youtube.com/watch?v=WUFH7A565E0
I’m using these triggers with servo motors to control model railroad track switches. They work perfectly and allow me to slow down the movement to more closely model the real world. The only thing I don’t care for is that since virtually all servo motors are prewired with standard width female pin connectors. So why aren’t the pins installed on the trigger card?
Works as advertised. A very handy board!