This donation box was a commission for Milestones Living History Museum in Basingstoke UK. The brief was for a box featuring the animated logo of the museum with lighting, movement and sound.
Here I give some insights into the design process and show a video of the finished box.
Milestones is displayed as an old town with shops, vehicles and other artefacts. On the left of the picture is a penny arcade with old fair ground machines. Clearly a popular exhibit.
The outline sketch of the proposal showing the basic shape and size of the box. The commission was for an animated logo but to add interest I added a vehicle to collect coin donations and also some visible gears and cams controlling trees animated logo.
It seemed most apt to model one of the vehicles in the collection. This Thornycroft truck seemed to most appropriate. Shown with an indication of how the coins would drop out of the bottom into the money box. Rather than running on its wheels the truck runs on toothed rails. The result is that the wheels spin a little faster than the truck is moving. I wonder how many people will notice. A major design consideration was robustness as hopefully the mechanism will get many runs a day, day after day.
Sketches of the logo to get an idea of sizing. It soon became apparent that too man ethe logo in a line was impractical as the letters would be too small to have much impact.
A quick cardboard mock-up proved useful throughout the designing and construction.
The Thornycroft truck that was modelled for the box, in the museum.
Money collection is obviously and important element of a donation box. Here the coins are collected and roll into the truck. The truck has 3D printed inserts to ensure that the coins don't get stuck. The 3D printed coin collector took 4 attempts as the first 3 designs resulted in coins bouncing over the infra red sensor and not activating the machine. This version works flawlessly. The coin triggers the light turning from blue night time to sunshine yellow. The truck makes a starting noise and carries the coin across the box before dropping it.
The notes slot also has an infra red sensor that triggers a round of applause.
Vinyl transfers are used for the signage. The money box has a red glow from LEDs and pulses when money is inserted. I started with a fan to blow notes away from the sensor but this proved not to be necessary so I saved some wiring and driver pins.
The logo and the cams/gears are separate modules that slot into the box. The supports of the letters are 3D printed. The letters are plywood as are the gears and cams. All lit with red and white LED strips.
With sensors, sound, 3 motors and LED strips there needs to be a lot of electronics and wiring. The box is controlled by a Raspberry Pi Pico, left.The electronics need 12, 5 and 3.3 volts.
The box in situ. A coin has just been inserted as the truck is in "sunlight".
The box shape was changed from the mock-up with a sloping housing for the logo to make it easier to see. All parts are protected by 4mm Perspex.
The museum's animated logo that the box is based around.
Showing insertion of a bank note. The applause only sounds with notes, not with coins.
Attribution 3 licence
Mixkit Sound Effects Free License