Extendable Arm Extendable Arm

BackgroundBackground

Vincent Brown is the subject of our Vincent Brown is the subject of our research. After being in a car accident research. After being in a car accident Vince suffered injuries to his back that Vince suffered injuries to his back that rendered him immobile at the lower half of rendered him immobile at the lower half of his body, he also suffered injuries to his his body, he also suffered injuries to his arms where he lost the use of his trice arms where he lost the use of his trice pets thus becoming a Quadriplegia and pets thus becoming a Quadriplegia and has been wheelchair bound since then. has been wheelchair bound since then.

Proposition Proposition

Vince came to us at Wayne State Vince came to us at Wayne State University College Of Engineering with a University College Of Engineering with a proposition, he wanted us to design and proposition, he wanted us to design and fabricate a device to help him regain some fabricate a device to help him regain some motion with in his right arm. This device motion with in his right arm. This device was to be light weight and able to pick up was to be light weight and able to pick up everyday objects enough to bring it closer everyday objects enough to bring it closer to him.to him.

First GenerationFirst Generation

The First Generation of the arm was a The First Generation of the arm was a holed out steel tubing that housed another holed out steel tubing that housed another steel tubing that was used for the steel tubing that was used for the extension portion of the arm. It was power extension portion of the arm. It was power by a pneumatic air pump, and had a servo by a pneumatic air pump, and had a servo driven griper at the end. The arm was also driven griper at the end. The arm was also outfitted with a voice command function outfitted with a voice command function which gave the user control over the which gave the user control over the extension and opening function of the arm.extension and opening function of the arm.

FlawsFlaws

The major draw back of this arm was that The major draw back of this arm was that is was too powerful for the user. When is was too powerful for the user. When activated the arm would shoot out like a activated the arm would shoot out like a bullet instead of having a control extension bullet instead of having a control extension ..

The End-effectors The End-effectors

The end-effectors of the first generation The end-effectors of the first generation arm was a two point gripper, which was to arm was a two point gripper, which was to mimic the index and thumb of the human mimic the index and thumb of the human hand. This gripper was servo driven able hand. This gripper was servo driven able to pick up small object as well as larger to pick up small object as well as larger objects.objects.

Flaws Flaws

Wrist rotationWrist rotation

Voice CommandVoice Command

The activation of the arm was controlled The activation of the arm was controlled by the user giving a activation word, in the by the user giving a activation word, in the case of the first Generation it was “Max”, case of the first Generation it was “Max”, after receiving the activation word the use after receiving the activation word the use would then give the command. The user would then give the command. The user would either say “Max open” or “Max would either say “Max open” or “Max Close”.Close”.

Second GenerationSecond Generation

Although the fist generation had its flaws, it did Although the fist generation had its flaws, it did form the bases for the second generation. This form the bases for the second generation. This new model will be lighter then the first and have new model will be lighter then the first and have a new way to power the opening and closing of a new way to power the opening and closing of the gripper, it will also be one unit instead of a the gripper, it will also be one unit instead of a three unit device as the first one was. This three unit device as the first one was. This generation will also keep the voice activation generation will also keep the voice activation function that was used by the first generation function that was used by the first generation only this time no activation word will be used.only this time no activation word will be used.

Data AnalysisData Analysis

In Designing the second generation of this In Designing the second generation of this arm we meet up with Vince to record data arm we meet up with Vince to record data on the motion of his arm and the maximum on the motion of his arm and the maximum extension of his arm along with the extension of his arm along with the maximum reach of his arm and the maximum reach of his arm and the maximum amount he could lift.maximum amount he could lift.

Progress MadeProgress Made

Since the last update, we have completed Since the last update, we have completed the arm and have it operational. We have the arm and have it operational. We have completed the voice command program completed the voice command program that will recognize the user voice, also we that will recognize the user voice, also we have mounted the actuator and the power have mounted the actuator and the power source on the arm.source on the arm.

New Voice CommandsNew Voice Commands

As stated we have completed the voice As stated we have completed the voice command program for the chip. During the command program for the chip. During the last update it was thought that we could last update it was thought that we could get rid of the activation word “Max” this get rid of the activation word “Max” this would have made the code shorter and would have made the code shorter and made it little easier on the programmer, made it little easier on the programmer, but we now know that the chip we have but we now know that the chip we have choosen needs a activation word so that it choosen needs a activation word so that it can break out of its idle stage.can break out of its idle stage.

Commands/ActionsCommands/Actions

We kept the activation word “Max”, and for We kept the activation word “Max”, and for the command words we went with “Grab” the command words we went with “Grab” and “Release”. So for example if the user and “Release”. So for example if the user wants to pick up and hold an item the user wants to pick up and hold an item the user would say “Max” followed by “Grab”, and if would say “Max” followed by “Grab”, and if the user wanted to drop the Item the user the user wanted to drop the Item the user would say “Max” followed by “Release”.would say “Max” followed by “Release”.

New MotorNew Motor

In the last generation of the extendable In the last generation of the extendable arm a pnumatic air pump was used which arm a pnumatic air pump was used which shot the arm out uncontrollably, now since shot the arm out uncontrollably, now since we do not have to worry bout a extension we do not have to worry bout a extension of the arm we can use a more controllable of the arm we can use a more controllable Linear Actuator that opens and closes the Linear Actuator that opens and closes the end-effectors of the arm.end-effectors of the arm.

Linear Actuator Linear Actuator

The linear actuator that we have 4 inches The linear actuator that we have 4 inches long and can pull with the force of 150N, long and can pull with the force of 150N, unlike the pneumatic air pump that had a unlike the pneumatic air pump that had a uncontrollable release of air this one has a uncontrollable release of air this one has a slower but control release of 5mm/s.slower but control release of 5mm/s.

Mounting Mounting

To mount the power supply along with the To mount the power supply along with the linear actuator we had to find something linear actuator we had to find something that would not compromise the weight of that would not compromise the weight of the arm, out solution was to use a hose the arm, out solution was to use a hose clamp, there most commonly found in car clamp, there most commonly found in car engines. Also we found that if we mounted engines. Also we found that if we mounted the linear actuator on top of the arm it the linear actuator on top of the arm it would be out of harms way. Lastly as would be out of harms way. Lastly as shown before our circuit was mounted on shown before our circuit was mounted on a bread board, in practice we used a PCB.a bread board, in practice we used a PCB.

FinFin

Any QuestionsAny Questions