This section will describe Dewey's walking mechanism. When I started making Dewey, I intended him to be a kangaroo. However this did not work. Dewey uses two back set legs, a design I arrived upon after trying some front set, triple set, and triangular leg designs. Dewey’s drive motors are geared down 1:3 for torque, giving Dewey fairly good power. Dewey’s legs work by a small rotating beam that causes a larger beam to swing, Because of multiple attachment points, this swing motion has bean manipulate to make a walking motion. As Dewey walks, his legs bend and change shape, lifting his feet. I tried adding rubber grippers, but these made Dewey walk backwards. This is a good system, but Dewey is a little top heavy. Dewey’s high center of gravity forces him to fall under normal circumstances. Fortunately, I added two support beams to combat Dewey’s fall. Dewey’s legs also had a tendency to bend inwards, so I constructed a small spring-loaded set of linkages to push the legs outwards. Dewey’s large feet also help with this problem. Another problem that I had with the legs was the pieces popping out, I added some armor pieces and reinforced the axels, and now Dewey works perfectly. Dewey’s tail provides some extra support, and it carries much of his weight. In order to keep Dewey’s frame sturdy I added five shock absorbers to the tail.
Picture 1 The Right Leg
Picture 2 The Motor and Gears
Picture 3 The Spring system and linkages
Picture 4 The leg without the armor
Picture 5 The Shock absorbers in the tail
This section describes Dewey’s Head and Arms. When I was building Dewey, I wanted to give him a good head. I started with a design similar to Comet the Chameleon’s head. I used many bent beams to get a cylinder shaped head. I then added eyes and a lower jaw. The eyes were originally bulging out of Dewey’s head, and I changed them later on. I did not like the shape of Dewey’s head, so I added some bent beams and air intake pieces on the back of the head. This elongation made a nice head with the new eyes. I then added a tongue to the mouth and made a small compartment in the throat. This compartment is used to hold the “food” that you feed Dewey (I used blue zamor balls but you can use anything that is not to big). With the zamor balls, Dewey will only eat three, and will spit extra food out of his mouth. The sound sensor is used to detect food. The jaw is geared down for more control. Now for the arms. In many pictures, I see that some dinosaurs have short arms. I gave Dewey short arms to make him appear more natural and alive. The arms were originally connected to the NXT with gears. The NXT originally was on a pivoting bracket that would shift with the legs. This was unnecessary and I locked it. However, when the NXT shifted, the arms would move back and forth. The gears were removed and now the arms pivot freely.
Picture 1 Dewey’s Head, Arms, and food
Picture 2 Dewey’s mouth open
Picture 3 The Balls in Dewey’s Throat Compartment ( It looks almost like he has teeth)
Picture 4 The Gears for the Jaw
Picture 5 The Right Arm
The Section describes the locations and functions of the sensors. Because Dewey is a pet, I had to use his sensors for something interactive. I used the ultrasonic sensor for navigation and mounted it below Dewey’s chin and between his arms. I mounted the sound sensor so that it pointed into Dewey’s throat, allowing him to detect the balls as they are tossed into his mouth. The Sound sensor is covered by the back of Dewey’s head, so you will not see it unless you remove some pieces. The light sensor is mounted in a similar location to Comet’s light sensor, and it allows Dewey to detect the light ambience of his environment. Finally the touch sensor is mounted behind Dewey’s head. The touch sensor detects petting and is pointed upwards.
Picture 1 The Light sensor and touch sensor.
Picture 2 The Ultrasonic sensor
Picture 3 The sound sensor
Picture 4 The Light sensor
Picture 5 The Touch sensor
This section Describes Dewey's Program. Dewey uses a very lage and complex program to control his mood, walking, and eating. Dewey has five moods: content, sad, happy, hungry, and sleepy. Dewey uses five myblocks in the program. In the program, Dewey beeps, and then opens his mouth for food, if you give him food, he will swallow it and ask again. He will open his mout for times for food and then begin walking. When He is walking, He will turn away from objects if he sees any. If you pet Dewey, he will dance for a second, beep, and then wait for you to pet him again. If you pet him he will remain still and beep. If you do not pet him, he will begin walking . When walking at normal speeds, Dewey is content. When being petted, Dewey is happy. If you do not pet Dewey for a while, he will become sad and walk slowly. At a random time in the program, Dewey will become hungry again and ask for more food. If Dewey enters a dark area, he will slow down his walking, and fall asleep. He will snore slowly until the lights are turned on, and he will then yawn, and continue walking.
Please note that you will have to download all of the myblocks in this section and the next section to have the program.
File 1 Dino eat myblock
File 2 Dino Motor decide myblock
File 3 Dino Petting
File 4 Dino See
Her are the rest of the myblocks.
File 1 Dino yawn myblock
File 2 The main Program
If I uploaded the wrong myblocks, then please let me know
(You can see how Dewey needs the support beams in the picture).
This section describes the parts that make Dewey a dinosaur. Many dinosaurs have long tails that tapir off at the end. I gave Dewey a long, shock loaded tail that is jointed at the end. Also, Many dinosaurs have large heads (many have small ones too, but I like larger ones better :-}. Dewey has a large head with slanted eyes. Some dinosuars have three large toes on their feet, and Dewey has three large toes on his very flat paddle-like feet. Also, dinosaurs like the T-rex and velociraptors have shorter arms, so I gave Dewey short arms with two claws. I also gave dewey a small silver claw on his upper arm to give hima sort of muscle.
Picture 1 Dewey
Picture 2 Dewey's tail
Picture 3 Dewey's head
Picture 4 Dewey's foot
Picture 5 Dewey's arm