Control moment gyroscope by ECP

Z DCEwiki
Skočit na navigaci Skočit na vyhledávání

Educational four-axis control moment gyroscope - Model 750 from Educational Control Products (ECP).

Link to the product web page on the producer's site

Located currently at K26 lab.

Troubles:

  • the system is provided with the so-called turnkey solution, which means that besides the model itself, an amplifier and also the software was delivered.

Student projects finished with the system:

MATLAB® Controll using Real-Time Windows Target® and Humusoft Control Board

Individual Project
Krištof Pučejdl

Motivation:

  • Dedicated control software provided by ECP is very outdated. It requires old 32 bit processor architecture and the user interface does not match today's standards.
  • Most of the control models being used in education are controlled via MATLAB® using universal Humusoft control board. Using the same board to control different models is way more flexible and allows switching the controll PC's without need of hardware changes.

Goals:

  • Find the correct setup of Humusoft board according to pin-out specification provided by ECP.
  • Set up and run the RTWT® communication in MATLAB®
  • Describe the input values to actuators and output values from sensors.
  • Experiment with regulators and feedback control.

1. Model Description

Figure 1: Gyroscope Encoders and Motors


2. Humusoft board setup

Gyroscope Ampflier/Interface box uses 60-pin Flat Cable for connetnion with original ECP control board. 14 pins are used to provide power supply and data acces to four encoders (Encoder 1-4) and two Digital-to-analog converters that drive motors (DAC 1-2). All devices are described in previous section.
Each Encoder requires 4 wires. Two for TTL Signal data on Channel A and B, one for power supply (+5 Volts) and one for ground. Power supply and ground are common for all four encoders.
Each Motor requires 2 wires. One for input DAC Signal (input range +/-10 Volts) and one for ground.
The original pin-out specification provided by ECP (on request) contained several errors. Following specification table is already corrected.
Pin-out specification
Signal Description  Pin Number  Very Important Notes
Encoder 1 A Channel 25 TTL Signal
Encoder 1 B Channel 21 TTL Signal
Encoder 1 +5 V Power Supply 1 DO NOT MIX UP +5 Volt & Ground. Causes immediate damage to encoders.
Encoder 1 Ground 3 Encoder Power Common
Encoder 2 A Channel 26 TTL Signal
Encoder 2 B Channel 22 TTL Signal
Encoder 2 +5 V Power Supply 1 DO NOT MIX UP +5 Volt & Ground. Causes immediate damage to encoders.
Encoder 2 Ground 3 Encoder Power Common
Encoder 3 A Channel 13 TTL Signal
Encoder 3 B Channel 9 TTL Signal
Encoder 3 +5 V Power Supply 1 DO NOT MIX UP +5 Volt & Ground. Causes immediate damage to encoders.
Encoder 3 Ground 3 Encoder Power Common
Encoder 4 A Channel 14 TTL Signal
Encoder 4 B Channel 10 TTL Signal
Encoder 4 +5 V Power Supply 1 DO NOT MIX UP +5 Volt & Ground. Causes immediate damage to encoders.
Encoder 4 Ground 3 Encoder Power Common
DAC 1 Spin Motor 43 MAX +/- 10 Volts
DAC 1 Return 58 DAC 1 Common
DAC 2 Gimbal 2 Motor 44 MAX +/- 10 Volts
DAC 2 Return 59 DAC 2 Common

3. Simulink® Control block

4. Range and meaning of input/otput values