The Making of Number Five

February 13, 2023July 9, 2023 Dryad and Harpy

Inspired by the Boston Dynamics robot videos, steampunk art, and Girl Genius, the HipMonster team set out to make their robotic dog walk to take for a walk on our city street. This project ended up being a lot harder than we imaged and took two years to complete. This greatly impacted our work on the HipMonsters’ website which is just now being updated with new content. So, finally, we give you the making of Number Five!

Please note, this material is provided for entertainment and informational purposes only and is not a guide on how to create the designs. Please read our disclaimer.

Getting started on a DIY robotic dog projects — Getting Started

Base supplies to get started:

Brass Pipe Fitting, 4-Way Tee, Female Pipe (1, 1/4″ x 1/4″ x 1/4″ x 1/4″ NPT)
Brass Pipe Fitting, 90 Degree Barstock Street Elbow, 1/4″ Male Pipe x 1/4″
Brass Pipe Fitting, Barstock Tee, 1/4″ x 1/4″ x 1/4″ NPT Female Pipe
Black Steel Pipes ,close nipple pipe, 1/4 in. x 8 in, Black, 5 Pack
Black Steel Pipes, close nipple pipe, 1/4 in. x 6 in, Black, 5 Pack
Black Steel Pipes, close nipple pipe, 1/4 in. x 2 in, Black, 5 Pack
Hex Nipple Coupling Set – 1/4-Inch NPT x 1/4-Inch NPT,Solid Brass, Female Pipe
3/8 Inch Stainless Steel Cable Clamp
90-degree Swivel 1/4-Inch Male NPT x 1/4-Inch Female NPT
Clear 6mm OD 4mm ID Polyurethane PU Air Hose Pipe Tube Kit 10 Meter 32.8ft
Pneumatic Rotary Lever Hand Valve 1/4” N PT Air Flow Control 3 Position 4 Way
Pneumatic 16mm Bore 150mm Stroke Air Cylinder Double Action
Bike Pump

Building on our experience creating Number Three, we used piping to build the skeleton for the robot. To make it stronger to withstand the force of walking we used 1/4-inch steel pipes and pneumatic pivot joints rather than PVC tubing. After that, we assembled the legs using the pivot joins to allow the legs to move.

Assembly begins on a DIY robotic dog project. — Assembly begins!

After the legs were completed, we built a spine to help attach the legs and provide an attachment platform for the batteries, controller, and engine.

DYI robotic walker skeleton is coming together — The skeleton is coming together

When Number Three moved, the legs would frequently come loose so we made sure to be attached tightly to the spine. We knew from other robots we built that the vibrations of a running robot tended to unscrew bolts and screws. So, getting everything put together as tight as possible is essential.

Final tightening of the frame of the DIY walking robot dog — Final tightening of the frame

The spine takes a little patience to screw together because we used three parallel sets of pipes for strength. It proved difficult to screw them in at the same time and the best approach was to take it slow and calmly.

Side view of the completed DIY robotic dog skeleton — Side view of the completed skeleton

This is the side view of Number Five with most of the pneumatic pistons in place. We had two powering the back legs and four to power the front legs which did most of the pulling. We found from the full-scale test pull was better than push for control. If a front leg got stuck and the back legs still pushed forward the robot would veer to the left or right.

Below is a top view. The front part of the skeleton does not have a spine. This was originally to enable us to adjust the strides of the legs but that ended up being too finicky and we instead locked them in place. Sadly, we don’t have a clean attachment point for a head if we ever want to add one.

Top view of the completed DIY robotic walker skeleton — Top view of the skeleton

Next, we started connecting the air tubes to the pistons. We first laid out how the piston would attach to the frame then cut the tubes to link them to the engine. We made sure that they were long enough not to get yanked out, but short enough not to get caught in the robot’s legs.

Fitting the pneumatic tubes to power the piston on the DYI robotics dog — Fitting the pneumatic tubes

The tubing took a few attempts to get the length right. It is better to be too long than too short, so we have a bag filled with little bits of extra tubing. The tubing connects the piston to the engine. In the beginning, the engine was a bike pump powered by a kid but the final version would have a car air pump.

While attaching the pipes we recommend color coding the pipes with a little bit of nail polish or colored tape. You want the legs to be connected oppositely. If a right piston is rigged to push when the air is redirected, you want its mirror to pull.

Each piston has two connections:

one at the top which makes the rod push out,
one in the middle pulls the rod back.

Below is a gif of two pistons connected in opposition. This will enable the robot to walk with a stride.

Testing the pistons on the DYI Robotic dog. — Testing the pistons

Below is the first full-scale test. We used a bike pump to better control power. The bike pump worked remarkably well for most of our small-scale tests and was significantly quieter than the air pump. Plus it is cool to power a robot with a bike pump. As you can see… this test failed hilariously.

First test of the DYI robotic dog. — Test number one

The first test showed that controlling double-jointed legs was very difficult so we decided to shorten the legs as well as do tons of additional modifications. With lots of tubing, it tangles easily and it is hard to figure out where the problem is. We also added knees to stop the legs from overextending and falling.

Setting up the tubing on the DYI robotic dog — After tons of modifications

The second full-scale test was much more successful and operated as we expected. This floor has a slight downward tilt but it also works in the opposite direction; admittedly a bit slower. It is still operated by a manual switch but the engine is now a car pump.

Test number 2 of the DIY robotic dog — Test 2

At this point, number five was powered externally and controlled with a manual switch. Our final goal was to be able to walk number five in our neighborhood on Halloween, so we added batteries, electronic air flow controls, and a remote control.

Adding wiring and remote control to DIY robotic dog — Adding control units

The engine was an old portable air compressor for car tires that was super light and used little power. To make Number Five portable, it needed to run on a 12-volt battery which meant all the electronics had to run off of 12 volts as well. Luckily 12 volts is the standard power supply so finding the right parts wasn’t too difficult.

Adding pump to DIY robotic dog — Adding the engine

At this point Number Five was completely self-contained and controlled by a remote. We moved the battery to the center of Number Five to give it a lower center of gravity. When we first put it together the first time it was clear it would fall over easily if the battery was on top. So we quickly built a lower platform that rested between the leg. The pump was light enough to stay in the back clear from the movement of the front legs.

DIY Robotic dog walking, Made by kids

Here is the first test of the fully remote Number Five. We had more slippage than we had in the prior tests; the weight of the battery and air pump impacted the wheel traction more than we expected. So back to tinkering…

The key improvements this time were:

A rubber wedge in the wheels made them only spin in one direction
Shifting more weight forward.
Extended the forward stretch of the front legs giving a lurching motion forward that was very effective on flat or downhill surfaces.

DIY Robotic dog walking on sidewalk — Taking Number Five for a Walk

After the modifications were complete, the sister team was ready to take Number Five for a walk in our neighborhood! Number Five worked well on the rough city sidewalks and could even manage to walk up a slight incline as shown in this clip. Downhill Number Five went almost too fast. We have learned a ton and stay tuned for the next modifications!

For high res videos of Number Five in action check out our YouTube Channel!

Happy Creating!

DIY Pump Drill

June 19, 2020July 9, 2023 Dryad and Harpy

The Hip Monster’s sister team has created a DIY pump drill. Pump drills are ancient tools used by many cultures including Native Americans. The sisters got the idea from seeing pump drills made by the Miwok tribe who used to live in California.

Please note, this material is provided for informational purposes only and is not a guide on how to create the designs. Please read our disclaimer.

Supplies for a handmade pump drill. — Some of the supplies

Equipment:

saw
drill
spade drill bit ~1 inch
drill bit 1/8 inch
spokeshave
sandpaper
strong string
bee’s wax
three long, straight branches

Branches:

1) shaft: the centerpiece of the pump drill. Look for a long, straight, and thin piece of wood.

2) spindle whorl: Attached near the tip of the shaft and makes the drill rewind. This piece should be heavy and thick enough the shaft can go through it.

3) handle: What you hold onto. This piece should be just thick enough for the shaft to go through.

First, you pick out three straight pieces of wood, one long and skinny, and the other two thick. Make sure the handle and the spindle ones are thick enough for the shaft to go through. Cut off the extra parts making sure to leave a bit extra on each end.

This se should look like this. The extra inch on each side of the sticks are so you can secure them to a vice for shaving.

The first one will be the spindle, the second the handle, and the last the shaft.

Next, spokeshave the pieces to make them smooth. Be very careful while spoke shaving you don’t want to make any of the pieces too thin or curved. Continuously flip the piece over to get to make all the sides are even. Sometimes when there is a knot or we accidentally cut into the wood, an adult can help smooth it out. If you have finished spoke shaving but don’t have enough time to stain or wax it, soak it in water so it doesn’t dry out to much.

For the main shaft, spokeshave till it is as straight as possible. To find out which side to shave roll the stick on a table and see which part is bent up. For the handle and spindle, you just need to get the bark off.

Now cut the piece to the right size. Make sure the thin one is the longest because that would be the main piece that supports everything else. Measure everything out the right size before you cut it.

Sand the pieces to make them really smooth. Spend more effort on the shaft. Remember, the shaft needs to be smooth and straight for the pump drill to work. They should look like this when done. Drill the holes in the two thick pieces. The with of the holes should be a bit bigger than the diameter of the shaft. When drilling, go slowly to avoid splitting. Make sure you drill in the middle of the wood. When done you should have two big holes in the large pieces big enough for the shaft. For drilling hole likes these where the edge of the drill bit comes close to the vice we let an adult do the final set up and test.

After you have drilled all the holes apply bee’s wax. The bee’s wax makes them smooth and help avoid splitting.

To apply the bee’s wax use an old towel. Since bee’s wax does not go bad, we use the same rag repeated for other projects.

Drill two holes at the tip of the shaft the same width as the string you will be using. Measure the string and put the string through it.

Now drill holes at both ends of the handle. Make sure the hole is in the same direction as the shaft hole.

Next, assemble the pump drill by sliding the shaft through the handle.

Then loop the string through the two holes you drilled in the handle.

Adjust the string so that the center stick if a little less than halfway down the pole. Then tied knots on both ends of the string.

Now slide the spindle onto the shaft.

Use a thin board of wood like the one shown in the photo and break off a strip.

Wedge the strip of wood in the gap to make the fit tight. Add more strips of wood as needed. The spindle should not be able to move.

And finally, cut a slot at the end of the shaft by cutting two parallel cuts. Then use a chisel to clean up the notch. Secure a sharp stone shaped like an arrow tip with string.

Yay! You finished!

Now you know how to make a DIY pump drill!

You use the drill by first winding it up. Then gently push down on the handle. Let the string rewind itself (thanks to the spindle whorl). Do not push the stick up but let the pump drill wind back then, again, gently push down.

Happy Creating!

Wand: Flame Tamer

June 19, 2020February 16, 2023 Dryad and Harpy

Every wand we craft has unique mythos and a special spell. This wand is called the Flame Tamer.

Handcrafted DIY Wooden Wand with rosemary

Mythos

Flame Tamer was created on a hot sunny day which gave its power to control fire.

Special Spell

Control fire.

First, create a circle of fire. Then speak the incantation:

ignis coercere

While waving the wand in a circle then thrusting the wand through toward the flames. Focus your mind on an animal, like a hawk or a wolf, that you are most aligned with. The fire will assume the shape of that animal and will obey your commands.

It is 16 inches long. This wand was made from pine and was soaked in rose petals and red clay. it was spoke shaved with a small bend in the middle.

Happy Casting!

Handcrafted DIY Wooden Wand

Wand: Scarlet Sunset

May 20, 2020February 16, 2023 Dryad and Harpy

Every wand we craft has unique mythos and a special spell. This wand is called the Scarlet Sunset.

Handcrafted DIY Wooden Wand with a book

Mythos

Scarlet Sunset was crafted as the sun was setting so its magic is strongest at night. For difficult spells, it is recommended to wait till a new moon. It plays well with fire and can even use fire as a healing energy to cure people and creatures.

Special Spell

Incendium Purgatio (Fire purification)

It is 14 3/4 inches long. Made of poplar grown in the Hip Monster’s realm. The wood was spoke shaven straight, soaked in oil with a rosemary and chives blend then polished with bee’s wax.

Happy Casting!

Handcrafted DIY Wooden Wand with a book

Sun-Moon-Earth Orrery

May 8, 2020November 15, 2023 Dryad and Harpy

Getting started

Need to track the moon phases for that perfect time to cast a spell? Worried about when you are due to change into a werewolf?

The following instructions are for a quick DIY Sun, Earth, Moon Orrery we did for a school project. This is suitable for ages 6 to 12 but may need adult supervision. We were inspired by this article in instructables.com but needed a much simpler design.

Please note, this material is provided for informational purposes only and is not a guide on how to create the designs. Please read our disclaimer.

Equipment

Equipment:

Drill
Pliers
Wire Cutters

Parts:

Plywood (10 X 10 inches)
4 inch bolt with 3 nuts and 3 washers
2 inch bolt with 3 nuts and 3 washers
3 foam balls of different sizes
9 inches of thick wire (may use coat hangers)
5 inches of thin wire (may use pipe cleaner)
Foam padding

Step 1

First, measure the center hole for the main screw. This screw will support the Sun, Earth, and Moon.

Step 2

Next, drill the hole and push the large screw through the hole and secure it with a washer and bolt.

Step 3

Turn over the base and stick four foam pads on the bottom. We used one large foam pad for furniture and cut it into four pieces. These foam padding will prevent the center bolt from scratching the table when placed upright.

Step 4

Turn the base back over and make sure the foam padding is tall enough to prevent the bolt from scratching the table. If not, then add another layer of foam. Next, screw another a nut to the halfway point on the bolt and then put a washer on top.

Step 5

Now we need to make the support wire for the Earth. Take the larger wire and bend both ends using a screwdriver as shown. The goal is the make the loops tight enough so the bolts are secure when threaded through them.

Step 6

Here, both ends are ready to secure the Earth to the center shaft. Notice one loop is smaller than the other. The larger loop is for the center bolt; the smaller one is for Earth’s bolt.

Step 7

Now, thread the smaller bolt through the smaller loop.

Step 8

Secure the bolt to the arm with a washer and nut. Then screw a nut halfway up the bolt. This bolt will serve as support for the Moon’s arm.

Step 9

Next, create the Moon’s arm. Bend the thinner wire similar to the Earth’s arm but only put a loop on one end. Bend the other end up to support the Moon.

Step 10

Now connect the thin wire to the screw on Earth’s arm and secure with a bolt.

Step 11

And we are nearly there! Just connect the thick wire to the screw and put a washer and bolt on top. Make sure to screw on tightly, the weight of the arm can make it droop.

Step 12

And finally we are ready to add the Sun, Earth, and Moon. The smallest ball is the Moon and goes on the smallest arm. The Earth is the mid-sized ball and put onto the outer bolt. The largest ball is the Sun and placed on the center bolts. You can paint the balls as the final step if you want to.

Putting it all together

The Sun, Earth, Moon orrery is almost complete, we just need to assemble! Here are all the pieces laid out. We substitute the foam balls in one build with a ping pong ball for the Sun and felt balls for the Earth and Moon.

Enjoy

You now have your own Sun, Earth, Moon Orrery and predict the next eclipse or start planning for the next full moon!

Keep a watch out for werewolves!

Wand: Night View

May 5, 2020February 16, 2023 Dryad and Harpy

Every wand we craft has unique mythos and a special spell. This wand is called the Night View.

Handcrafted DIY Wooden Wand in a garden

Mythos

The wand Night View has a darker side. Made of poplar and dyed in dark herbs she is ready for night time adventures!.

Special Spell

Noctem Visus (Night Vision)

It is 13 1/2 inches long. Made of poplar grown in the Hip Monster’s realm. The wood was spoke shaven straight, soaked in oil with a blueberries and mint blend then polished with bee’s wax.

Happy Casting!

wooden dyi wand with fake hand wooden diy wand