The daily happenings in the creation of the BurningMan artcar GravityBowl
Some generous friends helped us move and pack the car:
We rented a 24' truck for transport:
To fit the pieces we stacked them up, basically flipping the car on top of itself. Three pieces in place:
One piece left, the shop is looking empty:
All packed!
We'll be back from our test drive in the Black Rock Desert in two weeks. Check in early in September for photos and movies of the car in action!
Made a lot of last minute progress. The network code is now working and the wheels can be turned and rotated via the central console.
Time to pack it up! The GravityBowl is significantly wider than a highway lane so we need to break it apart to move it. The car breaks in to 7 pieces - a floor and six pie shaped wedges.
First we put the car on blocks and remove the tires:
Then we disconnect the wiring. Two main wiring harnesses (for lighting), network cables and battery cables pull out of the individual sections and wrap up for shipping storage in one main section:
Then we remove the floor:
Unscrew each of the sections:
Here's the disassembled car in six sections:
The whole process took about 3 hours.
All five of us enjoyed testing the newly made cushions, basking in the blue glow of the Gravity Bowl, and listening to its sound system.
Simon gave the motor controllers a workout. (See video!)
A mixed and late night last night.
On one hand we got the drive shaft rotating accurately under computer controlled power. Here is a video of one of the drive shafts doing quick 60 degree turns.
Rotating Wheel
There is a bit of oscillation, but that should be seriously reduced once the wheel is under load (the car is still up on blocks).
On the other hand, we managed to blow up one of the motor controller boards. Hopefully the components weren't too badly damaged and we can repair the board, or Simon has a spare board and we may be able to piece together enough to build a new one.
Storage compartments are now complete and painted red. They contrast well with the cushions:
Cushions look great on the car:
And are damn comfy too!
Simon, Lars and myself left the shop tonight at 2:30am. In the course of testing all three wheel assemblies we found two bad cables and damaged a board, which was very exciting! Simon has it all under control.
NOTE: In light of the additional work that's required to repair the board, and in light of how useful it's been to test the electronics in situ we're not going to disturb a good thing by taking the car apart for testing. We gonna work through till the end. We can test the backup system on site if need be.
The women of Groovig have been hard at work on the cushions:
They are looking great:
...thoroughly testing them for your safety:
The amount of wiring in the car is getting pretty insane.
Getting into the tight spaces can be a challenge:
Once inside it's not too bad:
Kevin sqeezed in too:
Here's the main junction for the lighting:
Tonight was a significant event! We got a chance to do a some testing of the wiring, control box, and the motor controller circuits. Simon brought in his laptop with a debugger, and took current readings as he powered the drive motors for a fraction of a second. (Well, it only sounded like a small "click".)
Geoff finished wiring up the backup system, with a two-pedal arrangement which can drive one wheel or all three together. Simple, but it works! We got to hear the drive motors roar!
Some words of wisdom from Kevin about lessons learned tonight...
1. Fuses are good! We discovered this burning through several 10amp fuses until we realized that the diodes on the contacters were causing a short. The diodes are in the right direction for the main control, and the wrong direction for backup mode.
2. Disconnecting the power completely before messing with wires is highly recommended. We burnt through a thin wire that accidentally shorted with a loud ZZZZAAAPPPPPP which scared the hell out of us.
3. 24V will probably be too fast. But we can re-wire it for 12V very easily.
4. Chains are loud. Sorry. I shoulda used belts or gears.
Geoff and I got the back up system working. As Simon predicted it is simple and it worked. Geoff's pedal arrangement can drive one wheel or all three together.
However! We learned a few things:
1) Fuses are good! We discovered this burning through several 10amp fuses until we realized that the diodes on the contacters were causing a short. The diodes are in the right direction for the main control, and the wrong direction for backup mode.
2) Disconnecting the power completely before messing with wires is highly recommended. We burnt through a thin wire that accidentally shorted with a loud ZZZZAAAPPPPPP which scared the hell out of us.
3) 24V will probably be too fast. But we can re-wire it for 12V very easily.
4) Chains are loud. Sorry. I shoulda used belts or gears.
5) A kill switch that cuts all power at the main fuse panel is pretty essential for safety, i.e. the backup control system has no "Off" switch without it.
This weekend everyone pulled the stops out and accomplished huge amounts of work!
- Final wiring on the vehicle is virtually done.
- The back-up control system has been designed and about 75% completed.
- Headlights and interior lighting are complete. More lighting is in the works.
- We had another guest helper, Nancy aka "Rosie the Rivetter", help with doubling up rivets on the interior.
- A number of the seat cushion foam pieces have been cut.
- And! the fabric is all cut including a big round cushion to fill the center.
Helping Children with Autism
