The complete bill of materials needed for the whole model is here.

The assembly guide shows, how to make following things:

  • Frame
  • Pendulum segment
  • Motor segment
  • FPGA shield

Frame

The frame is constructed from three aluminum profiles 40x40, 8 mm slot I-TYPE. The configuration and recommended lengths for 20 pendulums with two motors are depicted in the following figure:

config_alu_profile

Pendulum segment

The pendulum segment is designed as a combination of off-the-shelf and 3D-printed components.

Requirements

  • Spring
  • Bearing
  • Pendulum’s Support
  • Pendulum’s rod
  • Rotary encoder
  • Pendulum’s block
    • Inner block
    • Outer block
  • Weight holder
  • Screws
    • M3x14 hex socket button head screw (Qty.: at least 2x)
    • M6x16 hex socket cap screw (Qty.: 1)

Instructions

  • The configuration of the pendulum segment is here: https://a360.co/3uP4RIG.

    • Insert the bearing into the support
    • Insert the inner block into the bearing
    • Attach the encoder to support using 2 diagonally placed screws or all 4 screws (M3x14)
    • Place the outer block onto the inner block and the encoder
    • Insert pendulum’s rod with weight holder into the outer block
    • Secure weight holder with a small screw if necessary.
    • Insert the spring into the outer/inner block
    • Attach the support to the frame with M6x16.

config_alu_profile

Encoder cable

Requirements

  • 4-wire cable
    • Length of the segment: from 40 cm to 1 m.
  • Connector JST ZPDR-18V-S with 4 contacts SZPD-002T-P0.3
  • Connector Molex 55935-0410 with 4 contacts Molex 56134-9001
  • Crimping tool (recommended: PAD-11 ENGINEER)

Instructions

  • Get desired length of the cable from the encoder to the FPGA Shield. Note, that the cable could be inserted into the support.
  • On both sides, crimp the conductors and insert them into the connectors.
    • For the JST ZPDR-18V-S, use the contact SZPD-002T-P0.3
    • For the Molex 55935-0410 use the contact Molex 56134-9001
    • See picture below of the desired cable configuration. Note, that because the JST ZPDR-18V-S was not available at the time of the assembly, we had to buy JST ZPDR-20V-S and cut off a part of the connector.
    • Note, that the order of colors is not the same on both connectors.

config_alu_profile

Motor segment

Requirements

  • NEMA17 1.8° stepper motor
  • 3D-printed motor support: https://a360.co/3M9fMnV
  • 3D-printed connecting block
  • Motor Driver (Pololu Tic T249)
  • Screws
    • M3x14 hex socket button head screw (Qty.: at least 2x)
    • M6x16 hex socket cap screw (Qty.: 1)
  • USB-B cable for connecting motor driver to PC.

FPGA shield

Requirements