APA-I

OVERVIEW / DESIGN / CONSTRUCTION / PERFORMANCE

The APA-1 is an effort to make a multistage coilgun and experiment with a new charging, power source, switching, and control systems. Nearly all structural parts are aluminum with the only steel being low carbon casings for the accelerator and injection coils and the machine screws. All parts were cut, sanded, and shaped by hand with just a hacksaw, file, and sandpaper (including the handle). The only exception is drilling, which is primarily done with a drill press as reasonable accuracy is required.

STATS:

  • General:
    • Designation: APA-1
    • Name: Advanced Pulse Accelerator 1
    • Stages: 2 + Injector
    • Design Type: Handgun
    • Loading Type: Auto-loader Solenoid/Magazine
    • Switching Type: IGBT 4 x HGTG27N120BN
    • Clamp Diode: 2 x RHRG75120
    • Topography: Standard Dump and Quench
    • Trigger: Infra-Red Optologic Interrupt Sensors + Timing IGBT Driver
    • Charging:  6 Series Lithium Polymer Cells (NEW 2015)
        • Pack Nominal Voltage: 22.2V
        • Pack Rated Capacity: 800 mAh 850mAh
        • Pack Rated Discharge Rate: 15 C ( 12 A ) 45-90 C ( 76.5 A )
        • Pack Nominal ESR Measured: ~330 mOhm 74 mOhm
    • Charger Type: High Power Flyback Converter >70% Efficiency.
  • Coil Description:
    • Injector Coil Design:
      • Wire Size: 24 Gauge
      • Length: 22.2 mm (0.875 in)
      • Layers: 20
    • Primary Accelerator Design:
      • Wire Size: 20 Gauge
      • Length: 22.2 mm (0.875 in)
      • Layers: 6-12
      • Encased in Slotted Low Carbon Steel A513
    • Secondary Accelerator Design:
      • Wire Size: 20 Gauge
      • Length: 31.75 mm ( +-1 mm) (1.25 in)
      • Layers: 6-12
      • Encased in Slotted Low Carbon Steel A513
  • Capacitors:
    • Injector Coil-
      • Capacitance: 47-94 uF
      • Voltage: 400 VDC ( To 450 V)
    • Primary Accelerator-
      • Capacitance: 1120 uF
      • Voltage: 400 VDC ( To 450 V)
      • ESR: 178 mOhm
    • Secondary Accelerator-
      • Capacitance: 1120 uF
      • Voltage: 400 VDC ( To 450 V)
      • ESR: 178 mOhm
  • Projectile (Subject to Change after Performance Testing):
    • Projectile Material: Low Carbon Steel 1006 (Hollow Tail)
    • Diameter: 12.7 mm (1/2 in)
    • Length: 32 mm ( +-1 mm) (1.25 in)
      • Estimated Front Section: 9 mm (+-1 mm) (0.325 in)
      • Estimated Hollow Section: 23 mm (+-1 mm) (0.875 in)
    • Mass: 15 g (+-1 g)
  • Goal Measured:
    • Exit Velocity: ~40 m/s
    • Load Time: ~2s (Fully Charged Batteries)
  • Goal Calculated:
    • Accelerator Stored Energy: 227 J
    • Kinetic Energy: ~11 J
    • Weapon Efficiency: >5.0 % (GOAL)
    • Momentum: —- kg*m/s
    • Charger Power (New Batteries): > 115 W
  • Details:
    • Battery Protection: LTC2954 + PTC Resettable Fuse
    • Battery Charging: IMAX B6
    • Battery Fuel Gauge: N/A (2015)
    • High Voltage Capacitor Charger: LT3751
    • Timing: PIC 12F509
    • IGBT Gate Driver: FAN3122T
    • IR Optical Sensor:  QRD1114
    • Primary Display Driver: LM3914 and  ICL7107 (MQFP)

 

OVERVIEW / DESIGN / CONSTRUCTION / PERFORMANCE

© 2007-2015 Robert Wilsford.

Creative Commons License
This work by is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.