gregh
electronics, computers and scratchbuilding
Way back at the start of the year, there was a topic asking about our goals for the year. Mine was to add animation to my railway. I made a small start with my moving fireman and bouncing semaphores.
Now I’ve got a bit more adventurous.
I wanted a man sitting on a log outside his tent, with a fire. His right arm raises a drink to his mouth and his left arm moves a ‘stick’ to ‘poke’ the campfire. At the same time the fire will ‘flare up’ using flashing LEDs. All controlled by a Picaxe micro controller.
This is the video of the result:
[size=12pt]http://youtu.be/jw1xwUXWhuI
[/size]
Read on if you want to see how I did it……
I started with a cheap eBay figure holding a briefcase, on the right.
I cut the briefcase away and sliced off both arms at the shoulder.
I pivoted the right arm at the shoulder with a small screw. I cut the right hand off and rotated it to hold the mug made from a piece of plastic tube. The right arm is operated but a thin rod recessed into his coat, under his arm. (The screw head holes will be filled in someday.)
The left arm is pivoted at the shoulder and elbow. I had to make the forearm & hand from polyclay so I could get the correct angle for rotation. (the upper and lower arm have to overlap for the screw pivot). Movement is caused by the ‘poking stick’ pushing the arm. The stick is just a piece of brass wire.
The hat brim is 0.5mm styrene around the existing cap.
The tent is made from clay by my wife, and houses the batteries, circuit and servos. The whole scene is mounted on a piece of 2mm styrene, with the operating rods and linkages underneath.
Four NiMH AA 2200 mAh batteries are used. The circuit is just the Picaxe, a diode and a capacitor!
The fire has the 5 LEDs, with bits of aluminium foil ‘scrunched around them and then some red cellophane also scrunched around. The wood is real twigs, burnt in a candle flame. I used polyclay to makes the rocks around the fire and the axe.
Operation
The Picaxe 08M2 controls 2 servos and 2 ‘warm white’ LEDs. There are also 2 red LEDs, on all the time, and a flickering yellow LED (tea-light), on all the time. These are powered directly from the battery.
There are 4 separate programs in the Picaxe, with the ‘poking’ program controlling the other three.
The time intervals between each ‘poke’ of the fire are ‘random’, but around 20sec. The number of ‘pokes’ each time is also random, between 2 and 5.
While poking the fire, the drinking is disabled and while drinking, the poking is disabled.
The drinking program runs every 20 seconds but because it is inhibited while ‘poking’, it appears to be random also.
When the fire is poked, two white LEDs are flashed randomly to simulate the fire ‘flaring up’. The flaring continues for 3 secs after the poking stops.
At other times the two constant red LEDs simulate the coals and a flickering ‘tealight’ LED and one of the other LEDs is lit at ¼ brightness to provide some flicker.
Now I’ve got a bit more adventurous.
I wanted a man sitting on a log outside his tent, with a fire. His right arm raises a drink to his mouth and his left arm moves a ‘stick’ to ‘poke’ the campfire. At the same time the fire will ‘flare up’ using flashing LEDs. All controlled by a Picaxe micro controller.
This is the video of the result:
[size=12pt]http://youtu.be/jw1xwUXWhuI
[/size]
Read on if you want to see how I did it……
I started with a cheap eBay figure holding a briefcase, on the right.
I cut the briefcase away and sliced off both arms at the shoulder.
I pivoted the right arm at the shoulder with a small screw. I cut the right hand off and rotated it to hold the mug made from a piece of plastic tube. The right arm is operated but a thin rod recessed into his coat, under his arm. (The screw head holes will be filled in someday.)
The left arm is pivoted at the shoulder and elbow. I had to make the forearm & hand from polyclay so I could get the correct angle for rotation. (the upper and lower arm have to overlap for the screw pivot). Movement is caused by the ‘poking stick’ pushing the arm. The stick is just a piece of brass wire.
The hat brim is 0.5mm styrene around the existing cap.
The tent is made from clay by my wife, and houses the batteries, circuit and servos. The whole scene is mounted on a piece of 2mm styrene, with the operating rods and linkages underneath.
Four NiMH AA 2200 mAh batteries are used. The circuit is just the Picaxe, a diode and a capacitor!
The fire has the 5 LEDs, with bits of aluminium foil ‘scrunched around them and then some red cellophane also scrunched around. The wood is real twigs, burnt in a candle flame. I used polyclay to makes the rocks around the fire and the axe.
Operation
The Picaxe 08M2 controls 2 servos and 2 ‘warm white’ LEDs. There are also 2 red LEDs, on all the time, and a flickering yellow LED (tea-light), on all the time. These are powered directly from the battery.
There are 4 separate programs in the Picaxe, with the ‘poking’ program controlling the other three.
The time intervals between each ‘poke’ of the fire are ‘random’, but around 20sec. The number of ‘pokes’ each time is also random, between 2 and 5.
While poking the fire, the drinking is disabled and while drinking, the poking is disabled.
The drinking program runs every 20 seconds but because it is inhibited while ‘poking’, it appears to be random also.
When the fire is poked, two white LEDs are flashed randomly to simulate the fire ‘flaring up’. The flaring continues for 3 secs after the poking stops.
At other times the two constant red LEDs simulate the coals and a flickering ‘tealight’ LED and one of the other LEDs is lit at ¼ brightness to provide some flicker.
