Introduction
Integrated Solutions
- Custom Development
User Tools
Sidebar
dephyactpack
Table of Contents
Dephy Actuator Package
The Dephy Actuator Package is a turn-key solution for people who want to test FlexSEA's capabilities or quickly design a prosthetic limb. The Package consists of a custom brushless motor integrated with a FlexSEA-Rigid circuit and a minimalist enclosure, pre-loaded embedded software, and a full suite of high-level software and test scripts.
Features
- Fully integrated brushless motor (BLDC), power electronics and control logic
- Plug and play solution: no programming needed for most applications
- Cross-platform graphical user interface and full suite of C/C++, Python and MATLAB demo scripts
- Built-in high-performance controllers: current, position, impedance, and voltage.
- Built-in sensors and interfaces: 6-axis IMU, voltage, current, temperature, strain gauge amplifier, etc.
- Communication: Bluetooth Classic EDR, USB, RS-485, SPI, UART and I2C
- Safety features: battery I²t, motor I²t, voltage limits, temperature
Specifications
Table 1. Motor
| Mass | 230 g |
| Terminal resistance | 186 mΩ |
| Terminal Inductance | 138 µH |
| Torque Constant | 56 mNm/A |
| Diameter | 87 mm |
| Length | 17 mm |
| Rotor inertia | 1E-4 kg m2 |
Table 2. Housing
| Mass | 50 g |
| Material | 7075-T6 Aluminum |
| Finish | Black anodization |
Can be customized and/or engraved. Ask during the quoting process.
Table 3. Embedded System
| Mass | 41 g |
| Voltage | 20-50 V (5s-12s LiPo) |
| Commutation type | 4-quadrant Field-Oriented control (4Q FOC) |
| PWM frequency | 20 kHz |
| Max continuous motor current | 10 A (Note 1) |
| Peak motor current | 30 A (Note 1) |
| High level controller | STM32F427 180 MHz Cortex-M4 with floating-point unit (FPU) |
| IMU | MPU-9250 6-axis (3-axis accelerometer, 3-axis gyroscope) (Note 2) |
| Bluetooth | RN-42 Class 2 EDR Bluetooth module |
| Strain-gauge amplifier | One full-bridge channel, 5V excitation Gain = 203 |
| Motor encoder | Absolute magnetic encoder, 14-bits |
| Current sensing and control | Motor: 3-ch 12-bits sensing, 10kHz PI controller |
| Battery: ±20A, 900Hz bandwidth, 12-bits | |
| Safety protections (HW) | 52V TVS, 10A slow-blow fuse |
| Intrinsic sensors | Battery voltage, intermediate voltage, +5V bus, temperature, etc. |
(1) Higher currents can be used with a heatsink. Multiply reported and commanded currents by 0.40 to obtain Q-axis current.
(2) Magnetometer disabled by software – overpowered by the motor’s magnetic field
Quick start guide
Below are high level instructions and resources to get users started, as well as additional information to facilitate troubleshooting.
- Get the device powered up. This can be accomplished using a power supply or a USB cable. Then turn the device on by pressing the power button.
- If necessary the Actuator Package's firmware can be updated.
- Note: Keep in mind that the USB cable cannot power the motor.
- Note: The device's LEDs indicate its state and can be useful for debugging.
- Install and run the Plan GUI.
- Communication between your computer and the Actuator Package can be established over USB or Bluetooth.
- For the USB to work, the STM32 Virtual Com Port driver must be downloaded.
- Bluetooth is an other way to communicate with the actuator pack.
- The connection can be validated by streaming data.
- Plan can also be used to control motors.
- Note: Here are some recommendations on setting control gain values.
- With those functionalities verified, the demo scripts can be run. This allows the user to bypass the GUI and can serve as a template for future code in your target language.
- Before using the scripts make sure to read Actuator Package Software User Guide
Example Applications
Tips, Tricks & Best Practice
- Before plugging your ActPack, please review the Important Safety Warnings page.
- To get started on software read the Actuator Package Software User Guide
- Prevent USB connector problems:
- Make sure that the through-hole support legs are soldered to the PCB (one CM forgot to do it). It greatly reduces the chances of ripping the connector. Contact Dephy if you need assistance with this.
- Whenever possible connect & disconnect the computer side of the USB cable (USB A), not the ActPack side (USB Micro B).
- If you use USB other than for a bench-top experiment, you must provide strain relief on the cable. To be clear, people have been breaking them on benchtops too, so please be extra careful.
- Having USB connected will prevent a full power-cycle, even if you turn the module on & off with the push-button. After reprogramming one or more microcontrollers always do a true power cycle.
- When using Bluetooth we recommend waiting 15s between powering the circuit and starting a stream (from the GUI or the scripts). The RN-42 boots in a slow mode and transitions to fast after 10s. Starting a stream too soon can create issues.
- If there are Bluetooth connection problems with Windows, try restarting the Windows “Bluetooth Support Service” before rebooting.
Additional Resources
- Datasheet (PDF)
- 3D files (STEP) (26MB)
- Other than a few exceptions, all ActPack sold before 2019 use Rigid 0.2. Starting in 2019 we use Rigid 0.2B.
- Recommended USB cable: Tensility 10-02333
dephyactpack.txt · Last modified: 2020/08/27 13:43 by lmooney
Except where otherwise noted, content on this wiki is licensed under the following license: CC Attribution-Share Alike 4.0 International
