tir38

A while ago, during a job interview with Dr. Steve Dickerson from CAMotion, I was propositioned with a design problem: design an end effector which could grapple small rolls of tape (imagine the shape of 10 quarters stacked on top of each other). These rolls collect at the bottom of a ramp in rows of four. Each row needs to be grabbed and them moved to a packing station. The moving is performed by CAMotion’s existing hardware/control software and is ancillary to the end effector design problem. It is recommended that the grappling be accomplished by an already developed vacuum-suction system. So the problem simplifies to packaging the vacuum system in the end effector such that it maximizes payload capacity and speed.

I developed a solution which took inspiration from the multiple firing chamber design of the revolver handgun. Six rows of four suction cups are positioned in a circular fashion.

Sketch	Solidworks

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I have plans to utilize the Lego NXT system for several upcoming robotics projects. The success of these projects depends on the capabilities of the kit’s ultrasonic (US) range finder. I created a test rig with the US sensor and NXT brick and conducted several experiments in order to characterize the sensor.

Test rig: wood block, measuring tape, protractor, US sensor, NXT brick (from left to right).
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I recently purchased Lego’s new NXT hobbyist robotics kit. After familiarizing myself with the basic layout of the command module, available hardware and sensors, and third-party programing languages by building several single-task robots, I decided to use the NXT as a forum for my studies in SLAM robotics. As I have previously quoted, Dr. John Leonard of MIT says,

The problem of SLAM is stated as follows: starting from an initial position, a mobile robot travels through a sequence of positions and obtains a set of sensor measurements at each position. The goal is for the mobile robot to process the sensor data to produce an estimate of its position while concurrently building a map of the environment.

My goal and new perspective on the problem is to design a system which is as simple as possible. I immediately realize that much of the complication in SLAM systems lays in the timeliness with which the system processes information in real time. I know that some compromise between speed and simplicity had to be established, and in pursuing the most simple system, I am willing to sacrifice a lot in speed. So I have created what I am calling the “slam five robot”. The real acronym is S.S.S.S.S.L.A.M. which stands for “super-simple, super-slow, simultaneous localization and mapping robot”.

The system consists of three components: the physical hardware of the robot, the control algorithm which guides the hardware and sensors, and the post processing algorithm which interprets the sensor data. I begin here by describing the hardware and sensor setup.

Front view of the SLAM-5 bot, showing ultrasonic range finder and wiring for the drive motors.

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As a Christmas present, I decided to dye and paint a pair of shoes for my sister. I wanted them to match some clothes I bought her for her birthday. I also knew that I liked the Van’s Prison Issue #23 shoe (which I bought from Abbadabba’s), so I bought RIT Fabric Dye and generic fabric paint. The canvas/rubber combination of the shoe served as the perfect setup to add color without loosing the white soles. I started with the buff white / true white shoe, dyed it pink, and painted-on white flowers.
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When I found out that my roommates and I would eventually have to move out of our West 14th Street loft, I began exploring different buildings around Atlanta. My hope was that I would find another historic space that would provide us with a similar atmosphere and lifestyle. I realized that with so many buildings to keep track of, I needed to compile a list complete with pictures, maps, descriptions, etc. I collected possible buildings as I rode around the city on my daily commute or sometimes I would explore with the intent of finding new places. I was specifically looking for late 19th and early 20th century industrial/commercial buildings. These were exclusively brick-and-mortar buildings, most of which served as infrastructure to Atlanta’s vast railway lines. I furthermore became interested in finding and cataloging some of Atlanta’s different neighborhoods and districts.

My list is horribly incomplete and only contains buildings which I, myself, have seen and photographed. I recorded the street address and then performed a Google search to find information about the availablity of each building. When possible I include a description of the building, its current status, and what I think is the correct name of the building. Those with the most appealing location and amenities are denoted with a red star.

Atlanta Historic Architecture List

Even though we have now found a place to live, I plan to continue to fill in this list including more detailed pictures and descriptions and expand it as I discover new structures around Atlanta.