Pololu Mini Maestro 24-Channel USB Servo Controller (Assembled)

The Mini Maestros are the newest of Pololu’s second-generation USB servo controllers, offering more channels and features than the smaller six-channel Micro Maestro.

The Mini Maestros are highly versatile (and compact) servo controllers and general-purpose I/O boards. They support three control methods: USB for direct connection to a computer, TTL serial for use with embedded systems, and internal scripting for self-contained, host controller-free applications. The channels can be configured as servo outputs for use with radio control (RC) servos or electronic speed controls (ESCs), as digital outputs, or as analog/digital inputs. The extremely precise, high-resolution servo pulses have a jitter of less than 200 ns, making these servo controllers well suited for high-performance applications such as robotics and animatronics, and built-in speed and acceleration control for each channel make it easy to achieve smooth, seamless movements without requiring the control source to constantly compute and stream intermediate position updates to the Mini Maestros. The Mini Maestros also feature configurable pulse rates from 1 to 333 Hz and can generate a wide range of pulses, allowing maximum responsiveness and range from modern servos. Units can be daisy-chained with additional Pololu servo and motor controllers on a single serial line.

A free configuration and control program is available for Windows and Linux, making it simple to configure and test the device over USB, create sequences of servo movements for animatronics or walking robots, and write, step through, and run scripts stored in the servo controller. The Mini Maestros’ 8 KB of internal script memory allows storage of up to approximately 3000 servo positions that can be automatically played back without any computer or external microcontroller connected.

Because the Mini Maestros’ channels can also be used as general-purpose digital outputs and analog or digital inputs, they provide an easy way to read sensors and control peripherals directly from a PC over USB, and these channels can be used with the scripting system to enable creation of self-contained animatronic displays that respond to external stimuli and trigger additional events beyond just moving servos.

The fully assembled versions of the Mini Maestro ship with 0.1" male header pins installed as shown in the respective product pictures. A USB A to mini-B cable (not included) is required to connect this device to a computer.

Main Features

• Three control methods: USB, TTL (5V) serial, and internal scripting
• 0.25μs output pulse width resolution (corresponds to approximately 0.025° for a typical servo, which is beyond what the servo could resolve)
• Pulse rate configurable from 1 to 333 Hz ⁽²⁾
• Wide pulse range of 64 to 4080 μs ⁽²⁾
• Individual speed and acceleration control for each channel
• Channels can be optionally configured to go to a specified position or turn off on startup or error
• Alternate channel functions allow the channels to be used as:
  • General-purpose digital outputs (0 or 5 V)
  • Analog or digital inputs (channels 0 – 11 can be analog inputs; channels 12+ can be digital inputs)
  • One channel can be a PWM output with frequency from 2.93 kHz to 12 MHz and up to 10 bits of resolution
• A simple scripting language lets you program the controller to perform complex actions even after its USB and serial connections are removed
• Free configuration and control application for Windows and Linux makes it easy to:
  • Configure and test your controller
  • Create, run, and save sequences of servo movements for animatronics and walking robots
  • Write, step through, and run scripts stored in the servo controller

• Two ways to write software to control the Maestro from a PC:
  • Virtual COM port makes it easy to send serial commands from any development environment that supports serial communication
  • Pololu USB Software Development Kit (listed under the resources tab) allows use of more advanced native USB commands and includes example code in C#
• TTL serial features:
  • Supports 300 – 200,000 bps in fixed-baud mode, 300 – 115,200 bps in autodetect-baud mode ⁽²⁾
  • Simultaneously supports the Pololu protocol, which gives access to advanced functionality, and the simpler Scott Edwards MiniSSC II protocol (there is no need to configure the device for a particular protocol mode)
  • Can be daisy-chained with other Pololu servo and motor controllers using a single serial transmit line
  • Chain input allows reception of data from multiple Mini Maestros using a single serial receive line without extra components (does not apply to Micro Maestros)
  • Can function as a general-purpose USB-to-TTL serial adapter for projects controlled from a PC
• Board can be powered off of USB or a 5 – 16 V battery, and it makes the regulated 5V available to the user
• Upgradable firmware

Application Examples and Videos

• Serial servo controller for multi-servo projects (e.g. robot arms, animatronics, fun-house displays) based on microcontroller boards such as the BASIC Stamp, Orangutan robot controllers, or Arduino platforms
• Computer-based servo control over USB port
• Computer interface for sensors and other electronics:
  • Read a gyro or accelerometer from a computer for novel user interfaces
• General I/O expansion for microcontroller projects
• Programmable, self-contained Halloween or Christmas display controller that responds to sensors
• Self-contained servo tester

tester

Please see the Pololu Mini Maestro product page for the most up to date resources