Having a physical disability makes everyday things a real challenge. We created a product which makes it easier for the owner to feed his/her assistance dog. The owner wasn't able to feed his dog by himself.
The dog has to pull the cord and only one portion of food will come out of the box. It is possible to change the size of the portion. A smaller amount of food during the winter and a bigger amount during the summer. If the dog gets sick the portion can also be changed. The system can also be 'locked' so the dog won't be able to feed himself without the order.
This project was realised for Bart who helped us improve the product by testing several prototypes with his dog. Each trained dog is different and the command 'tug' (pulling) was the most efficient for our dog.
Step 1: Purchasing the Material
Most of the materials we used are cheap and easy to find.
The only thing that you will need to find is a fab lab (fabrication laboratory) or a site were you can order laser parts. The drawings needed for the lasercutting will be added at the end of the instructable.
Product needed :
ABS for the lasercutted parts / weights / cord / bin / wood / anti skid pads / screws / bolts / eye bolts / nuts / Tube with a 90° angle
Extra : Varnish and a tube
Step 2: Creating a Hole in the Bottom
First you will have to find the middle of the bottom of the bin.
Draw a rectangle of 10 cm in width and 20 cm in length maximum.
Cut out the rectangle using a simple knife and a ruler to create a straight line.
Step 3: Creating Holes for the Cord
The cord will be fixed on one side inside the bin on our mechanism explained later on.
The cord needs to glide easily, that's why we used eye bolts .
Two of them are need to be inside (hole 3 and 4). Fix an eye bolt in hole 1 on the outside of the box.
It will keep the cord in the correct possition and prevents it from handing against the wall of the box.
Hole 2 permits the cord to gofrom the outside to the inside.
The distance between the holes is not important.
Step 4: Creating the Part Needed for the Foot
The bin has to be higher so that a bowl can fit under it. It also needs a bigger surface on the bottom to prevent it from falling over when the cord is pulled.
The plans given below will help you to recreate the pieces.
The pieces are cut out of wood with a circular saw. Make sure that it's a durable type of wood.
If your bin has a different proportion you can adapt the drawings to have a perfect fit.
Step 5: Assembling the Foot
To assemble the foot holes with a diameter of 4mm will have to be made in the wood.
Afterwards simple M4 screws can be used to fix the boards to each other.
The two upper holes (M4) on the side boards are used to attach the bin to it .
Using M4 nuts and bolts you can attach the bin to the foot.
Step 6: Extra Anti Skid Pads
To prevent the bin from sliding when the dog pulls the cord you can add some anti skid rubber pads.
Step 7: Extra: Wood Finish
This step is just to create a nice and finished look by hiding the nuts on the front of the bin.
First you will have to saw a piece of wood. Then you will have to recreate the same holes as you made on your bin.
As you can see on picture the green holes aren't completely through the wood.
The nuts used on the front of the bin can be glued in the holes.
Once your are done you can simply screw it on the front of your bin.
Step 8: Extra: Varnish the Wood
Varnish the wood
The dog wil put his paws on it and the wood will get dirty.
When the house will be cleaned the bottom will be in contact with water.
The varnish will protect your wood from further decay.
Step 9: Assembly of the Food Portion System
First use the enclosed illustrator files to cut out the parts. For this you need acces to a lasercutting machine.
The video shows how to assemble the slider.
ABS is a food safe plastic and the grease will not be absorbed. It's also easily cleaned.
Step 10: Final Product: How to Use the Food Box
This video presents the final product, shows the initial problem and explains how the box is supposed to be used.