Bighak assembly guide

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The BigHak assembly guide below has been written as a guide for people to put BigHak together and check its functionality. It is only meant as a prompt for people already familiar with BigHak.

Before you start, make sure at least two people are available who are capable of carrying the assembled BigHak body work, and you have a clear area at least 2m x 4m. You'll need room for the assembled body work and the assembled chassis with room to access all around both. Also ensure you have all the items and tools on hand from the BigHak Packing List.

The instructions are in the order they are for specific reasons, before changing the order even a little away form that documented, ensure you have read and understood all instructions, as many of the tasks can only be performed in the described order.

Assembly Guide

Step 1 Tighten Chassis Screws

  • Check all screws on base of chassis are tight (don't over tighten, it crushes the aluminium)


Step 2 Check Keyway

  • Check the keyway clamps are tight


Step 3 Grooved Foam Insert

  • Attach grooved foam insert to back of chassis. The washers and wing nuts need to go on the inside of the chassis



Step 4 Fit Golf Cart Wheels

  • Fit golf kart wheels with the 'tube' on the inside, the valve on the outside. Tighten the nuts using a tool (spanner/socket preferred). These need to be very tight, as they loosen a little every time the wheels change direction. Put the clutches in gear and the chassis on the ground whilst tightening. Have a helper hold the motors in position, as the motor mounts are quite flexible.





Step 5 Fit Idler Axles

  • Fit idler axles. Front axle goes in top holes for running on grass/rough ground, bottom hole for running on concrete/tarmac/indoors
  • Put 1 washer on each axle
  • Put 1x long spacers on each side of front axle



Step 6 Fit Idler Wheels

  • Put jeep front wheels on front axle, jeep rear wheels on rear axle. Rear wheels are wider and have a pentagonal drive stub sticking out. wheel 'rims' (originally yellow, now painted black) face outwards.



Step 7 Fit Outer Spacers

  • Put 1 x short spacer on outside of each wheel


Step 8 Install Out Riggers

  • Push outriggers over shafts


Step 9 Tightn Shaft Collars

  • Tighten shaft collars in place using 3mm Allen key. the grub screws need to be fairly tight but be careful not to strip them


Step 10 Install Shaft Covers

  • Put the shaft covers over the ends of the shafts


Step 11 Install the Single 12V Electronics Supply Battery

  • Put 1 x 12V, 7Ah battery in rear battery compartment, connect electronics power cable (labelled "12V elec batt"). Note the unused red 'bullet' crimp connector and that the motor cables need to not be squashed or bent tightly.



Step 12 Install Battery Grommet

  • Put the black grommet in the aluminium battery tray wiring hole.


Step 13 Feed Motor Drive Cable

  • Feed motor controller cable from battery tray to motor controller


Step 14 Check Motor Control Connections

  • Check all connections to the motor controller box are correct and secure


Step 15 If Necessary Disconnect Battery Loom

  • If the battery harness (multiway red/black wiring loom) is connected, remove it now at the red deans connector


Step 16 Remove Battery Tray

  • Also remove the wooden battery tray


Step 17 Install Seat and Cushion

  • Put honeycomb seat and cushion in. Note the seat has a critical top/front orientation, both written on and denoted by the aluminium angle.
  • Position nosecone and rear bodywork together, upside down on ground/foam. Ensure the wiring in the nosecone is clear of the bodywork joint/screws.




Step 18 Assemble Bodywork

  • Screw bodywork together using 8 x 3x10mm wood screws. Don't over tighten





Step 19 Install Roundel

  • Turn over and connect roundel. note only one wing nut will fit (centre bolt)


Step 20 Install Bodywork on Chassis

  • Put bodywork on chassis


Step 21 Install Coach Bolts

  • Put 4 x M6 coach bolts through front of chassis, heads on inside, thread pointing out through nosecone
  • Swear whilst trying to put wing nuts on those coach bolts


Step 22 Install Wooden Battery Tray

  • Put wooden battery tray in position


Step 23 Connect Motor Controller Cables

  • Connect motor controller cable and ribbon jumper cable to connector on wooden tray. connectors are keyed but can go in either side. the ribbon cable must have the white end inserted in the back to back connector.


Step 24 Install The Drive Batteries in Tray

  • Position 8 x 12V, 7Ah batteries in battery tray, all facing same direction


Step 25 Connect Battery Wiring Harness

  • Connect battery wiring harness, positive connections first (red wires), secured with electrical tape. Then connect negative connections (black). Finally connect jumpers. If battery terminals are 1(-),2(+),3(-),4(+)....15(-),16(+), then the wiring harness negative connections go to 1,5,9,13, the positive connections attach to 4,8,12,16 and the jumpers join 2-3,6-7,10-11,14-15.

Battery tray wiring.jpg Photo shows negative and positive connections in place, but no jumpers.

Battery Tray wired.jpg photo shows batteries with jumpers in position.




Step 26 Clutched, Wiring, Laser Connections

  • Disconnect the motor clutches (wheels freewheeling)
  • Connect the wiring harness red deans connector to 'mains style wiring' 24V cable in chassis (not laser cable), labelled "24V motor ctrl". The motor fans should turn on.
  • Fish out RGB led cable (blinkstick) and laser (pew pew) cable from nose cone
  • Position electronics tray in position


Step 27 Connect Motor Controller

  • Connect motor controller ribbon cable to Arduino shield (2x15? connector, black end)


Step 28 Connect 12 V Electronics Power

  • Connect 12V electronics power cable to board (2 way white/clear plastic connectors)


Step 29 Connect Laser Cable

  • Connect laser cable (red deans connectors)


Step 30 Final Connections

  • Connect Blinkstick power and plug in to USB


You're done!, apart from testing...


Refer to the wiring diagram for the key for the switches

Testing Step 1 - Disengaged Clutches - Manual Mode

First test: disengage clutches, plug in manual joystick

  • Turn on power on joystick. battery indicate should show a single greed led. large red round lamp should flash then stay on solid
    • If red led is not solid, check motor/brake cables and power cycle
    • If battery is not showing green, check individual battery voltages. They should all be 12.5-13.5V?
  • Move joystick small amounts. brakes should be heard disengaging

Testing Step 2 - Engage Clutches - Manual Mode

Second test: engage clutches, use manual joystick

  • Drive slowly forwards, backwards, rotate left and right
  • If motor/wheels don't move in correct direction/amount, check motor wiring
  • Look/listen for wheels catching on bodywork
  • Check wheel nuts are still tight

Testing Step 3 - Remote Control Mode

Third test: RC mode

  • Disengage clutches
  • Plug in electronics control cable to motor controller
  • Turn on RC transmitter. look for solid orange light on receiver
    • If light not on, or is flashing, check transmitter is bound to receiver and transmitter is set to correct model type. this can be checked with a servo and 5v power outside of bighak
  • Put switches in correct orientation?
  • Check moving 'enable' channel on transmitter engages/disengages brakes
  • Make small movements on RC joystick, check motors both move
  • Engage clutches, check again with small movements

Testing Step 4 - Autonomous Mode

Forth test: auto mode

  • Magic?

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