FIELD OF INVENTION
This invention relates to a multifunction device for measurement and direct
display of height and time of free fall and auto-ranging stopwatch function in a
single device. It can be provided in the form of ball, which can be used as fun
device and as a versatile educational tool to conduct several experiments
related to science and maths. Further, the device is applicable for height, time,
angle, acceleration due to gravity measurements and study of experiments
related to motion under free fall and inclined plane, mechanics, proportions,
statistical measurements, stopwatch based time measurements and study of
experimental measurement errors.
BACKGROUNDIPRIOR ART OF THE INVENTION
Several educational experiments relating to mathematics and science are
required to be conducted by students at school. The experiments involve
measurement of acceleration due to gravity, stop watch based time
measurements and motion under gravity and on inclined plane.
A typical 'g' by free fall apparatus consists of a digital timer which measures
time taken by a small object to fall from rest for a pre-determined height under
free fall. Acceleration due to gravity 'g' is calculated according to formula as
follows:
Where : h= height of flight
: t = time of flight.
Typically apparatus consists of a ball release mechanism at top which triggers
start of digital timer and at the bottom of known height there is a contact plate
or ph~to-~awtehi ch stops the digital timer.
A Swedish Product is known to have been provided in the art in the form of a
ball with a provision to indicate only the time from the point of fall till it
touches an object. This can also measure acceleration due to gravity 'g' similar
to 'g' by free fall apparatus. It has an in-built digital stopwatch with LCD
display to display time between 0.01 to 29.99 seconds. The timing starts when
a switch on the ball is released simultaneously with the release of ball and
timing stops when the ball hits the floor. The maximum vertical drop of device
is specified at 12 meters on a soft surface.
However, the aforementioned prior art is associated with the following
drawbacks: -
- It does not involve much fun and variation in experimentation for
children as only one parameter i.e. Time in fixed range is displayed.
- The accuracy in result depends on skill of child to simultaneously release
ball as well as start timer switch.
- It cannot directly display height of drop.
- It has limitations of use for maximum drop height of only 12 meters as
claimed by manufacturer. Further the reliability of device is not assured
by manufacturer as display may fail and in event of height drops larger
than 12 meters.
- It cannot be used reliably for small height drops at sub meter level and
free fall height drops in all possible orientations as it is based on single
axis impact detection.
- The time resolution of stopwatch device is fixed 10 millisecond, whereas
better resolution in time such as 1 millisecond resolution is more
suitable for small height drops in free fall.
-4-
- The stop watch used in device is very much under-utilized as device
when dropped from 12 meters takes only about 1.6 seconds to reach the
ground. Moreover the digital stopwatch built in device cannot be used
for upto its rating of even 30 seconds as a standard stopwatch in time
measuring experiments.
Hence, it is required to develop a multifunction device which can address the
aforesaid drawbacks and can also measure and directly display height and
time of free fall and auto-ranging stopwatch function with better timing
resolution. Further, it can be used as a multipurpose fun device to play with
and an extremely useful tool in experimental education.
OBJECTS OF THE INVENTION
The primary object of the present invention is to provide a single multifunction
device for measurement and direct display of height and time of free fall and
stopwatch facility which overcomes the disadvantages associated with the prior
art and to also considerably extend the functions and range in measurement
for science and maths experimentation.
Another object of the present invention is to provide a multifunction device
which measures and directly displays the height and time of free fall on a
digital display with auto-ranging decimal.
Another object of the present invention is to provide a multifunction device for
measuring height and time of free fall which is efficient and reliable and does
not depend on user skill to release the ball. It should employ a novel technique
without use of any switch input from user and be able to automatically detect
the moment of release and free fall. Alternatively a lower cost version can
employ a switch activated by user to start a digital timer.
Another object of the present invention is to provide a reliable mechanism for
multi-axis impact detection to trigger the stop of digital timer, even for small
height drops in sub meter range as the device may hit the ground in any
orientation.
Yet another object of the present invention is to provide a multifunction device
for measuring height of free fall for small height drops in sub meter range and
directly display height with resolution of 1 millimeter.
Yet another object of the present invention is to provide a multifunction device
for measuring height of free fall for large height drops of several tens or
hundreds of meters and directly display of the same in auto-ranging mode.
Yet another object of the present invention is to provide a multifunction device
for measuring time of free fall and display the same in auto-ranging mode with
lowest resolution of 1 millisecond for less than one second measurements.
Further object of the present invention is to provide a stopwatch function for
time measurement from milliseconds to several hundreds of seconds in autoranging
mode.
Yet another object of the present invention is to provide a rugged and bright
LED display that can be viewed easily in dim light (indoor) and bright light (out
door) conditions. Alternatively a version of same device can use an LCD display
for long battery life.
Yet another object of the present invention is to provide the said multifunction
device for measuring height and time of free fall and stopwatch feature with
functionality of auto-shutdown of circuitry and user replaceable standard AAA
cells.
Still another object of the present invention is to provide a multipurpose device
which can be used for height, time, angle, acceleration due to gravity
measurements and study of experiments related to motion under free fall and
inclined plane, mechanics, proportions, statistical measurements, stopwatch
based time measurements and study of experimental measurement errors.
STATEMENT OF INVENTION
According to this invention, there is provided a single multifunction device for
measurement and direct display of height, time of free fall and auto-ranging
stopwatch function comprising of a housing accommodating a microcontroller
connected to release detection and multi-axis impact detection device, wherein
a plurality of switches are provided in connection with said microcontroller.
SUMMARY OF THE INVENTION
The present invention is provided in the form of a ball. So that, the same can
be used as a fun device to play as well as serve as an extremely useful tool in
experimental education. The device is used by students to conduct several
experiments related to math and science.
The device has a 3 digit electronics display with auto-ranging decimal to
directly display height and time and while considerably extending its
measuring range. The device display can be either LED for its robustness and
viewing in dim light (indoor) or bright light (outdoor) condition. Alternatively the
display can be LCD for long battery life
Time is displayed in seconds in four ranges of .OO 1 - .999, 1 .OO - 9.99, 10.0 -
99.9 and 100-999. Height is displayed in meters in four ranges of .001 - .999,
1.00 - 9.99, 10.0 - 99.9 and 100-999.
It has in-built release detection and multi-axis impact detection triggers based
on a novel use of 3-axis accelerometer with intelligent data processing which
automatically activates the start of digital timer upon release of ball in free fall
and stops digital timer whenever the ball impacts on a hard surface in any
orientation. This method provides accurate results as it is not dependent on
the skill of the user to release the ball even for sub meter level drop
measurement.
Alternatively the device has a switch trigger to start digital timer and a multiaxis
impact detection device based on switch closure which stops digital timer
whenever the ball impacts on the hard surface in any orientation. This method
provides a lower cost alternative and reliable operation even for sub meter level
free fall measurements.
The device can be used as a auto-ranging stopwatch for measuring time which
is also displayed in four ranges from miliiseconds to several hundreds of
seconds.
It has 30 seconds auto-shutdown functionality. The device has a rugged ball
shaped housing with a provision for the user to replace standard AAA cells. The
device contains microcontroller based intelligent circuitry which implements
the function of a digital timer with 1 millisecond resolution, auto-ranging
stopwatch function, height calculation function, auto-ranging electronic display
functionally, auto-shutdown and logic functions to detect release of ball based
on accelerometer or switch press and multi-axis impact detection based on 3-
axis accelerometer or switch closure. It can be used in a number of
experimental studies in science and maths. Representative experiments are
mentioned below.
Measuring Height of a person or building.
Measuring Acceleration due to gravity.
Measuring acceleration on an inclined plane.
Measuring angle on a sloping terrain.
Effect of gravity during Projectile Motion.
Stopwatch based time measurements.
Plotting Height vs Time graph under free fall and motion on inclined
plane.
Study of proportions.
Statistical measurements and sources of errors in measurements.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS:
Further objects and advantages of this invention will be more apparent from
the ensuing description when read in conjunction with the accompanying
drawings and wherein:
Fig. 1 shows: connectivity among different components of device according to
present invention.
Fig. 2 shows: impact detection device of the present invention.
Fig. 3 shows: multi-axis impact detection device of the present invention.
Fig. 4 shows: housing of device.
DETAIL DESCRIPTION OF THE INVENTION WITH REFERENCE TO THE
ACCOMPANYING DRAWINGS:
The present invention discloses a single multifunction device housed in the
shape of ball for measuring and direct display of height and time of free fall and
auto-ranging stopwatch function. Said device comprises of a novel auto release
and free fall detection mechanism based on a 3-axis accelerometer and
intelligent data processing. Further multi-axis impact detection, when ball hits
the ground, is also based on intelligent data processing of 3-axis accelerometer
signal. This constitutes one embodiment.
In another embodiment, said device and functioning comprises a switch based
release and multi-axis impact detection mechanism.
The device with the provision of 3-axis accelerometer is more accurate and is
not dependent on skill of user in releasing the ball in free fall as the moment of
release is automatically detected using intelligent data processing of 3-axis
accelerometer signals. However, both the embodiments of device work
efficiently and reliably even for sub meter level small height drops and when
the ball hits the ground in any orientation.
Now, reference may be made to fig. 1, wherein the microcontroller circuitry (1)
is connected to a switch (Sl) and another switch (S2). The switch (SI) is used to
switch on/off or reset. Said switch (S2) functions as a startlstop or mode
switch for display in stopwatch and height mode of the device. Further, the
microcontroller circuitry is connected to multi-axis release detection and
impact detection device (2) i.e. a 3-axis accelerometer for startlstop of timer.
Again, there is provision of a battery cell (4) for supplying power to
microcontroller and a display (5) to reflect time and height. Said cell and
display are connected to the microcontroller. Said display may be LED/LCD.
The time is measured with 1 millisecond resolution and displayed in seconds in
three numeric digits with auto-ranging decimal in four ranges of .001 - ,999,
1.00-9.99, 10.0-99.9 and 100-999.
Similarly, the height is measured with 1 millimeter resolution and displayed in
meters in three numeric digits with auto ranging decimal in four ranges of
.OO 1 -.999, 1.00-9.99, 10.0-99.9 and 100-999.
In another embodiment, the accelerometer can be replaced with a multi-axis
impact detection device (3). For the same, reference may be made to fig. 2,
wherein impact detection device comprising of a flexible spring (6) with a weight
(7) at its one end to recover a sudden jerk. Other end of the spring is fixed with
a nut (8) and another nut (9) is provided between the weight and fixed nut,
wherein the spring passes through said nut (9). Such an arrangement of spring
and nuts is provided in two directions being perpendicular to each other as
shown in fig. 3. This acts as two axis impact detection device, which is provided
with two contacts (10 and 11) to be connected with the microcontroller for
sensing impact like a switch connection being played. The same is also
applicable for 3-axis impact detection
Both the detection device (2 and 3) sense any impact with ground or rigid body.
A housing (H) in the shape of a cricket ball or base ball accommodates all the
components of device mentioned hereinabove. The housing with front part (F)
showing the display (D) with a window fixed with a filter.
Advantageous features
- Direct display of height and time under free fall.
- Auto sensing of release of ball when it is under free fall.
This enables accurate measurements of time and height under free fall.
- High accuracy and resolution in measurement of timing with a wider
range in measurement by means of a microcontroller.
- Display of the height (-001 to 999 meters) and Time (.001 to 999 seconds)
in four auto ranging modes.
- Auto ranging stop watch for multifunction use in experimentation.
- LED display as well as LCD display due to use of microcontroller. LED
displays are more robust and can withstand higher shocks without
damage besides having bright viewing in indoor and outdoor conditions.
LCD displays consume considerably less power and long battery life.
- It can be dropped on a soft surface from several times higher height than
12 meters compared to prior art and time measurements can be
observed for several times more than 30 seconds compared to known art
under free fall.
- It can be used reliably for small height drops due to lmilisecond timer
resolution and multi axis impact detection to reliable detect impact even
when the device falls in any orientation.
- Use of AAA size cells which are commonly available.
It is to be noted that the present invention is susceptible to modifications,
adaptations and changes by those skilled in the art. Such variant embodiments
employing the concepts and features of this invention are intended to be within
the scope of the present invention, which is further set forth under the
following claims:-

WE CLAIM:
1. A multi function single device for measurement and direct display of
height and time of free fall and auto-ranging stopwatch function in a
housing accommodating a microcontroller circuitry connected to free fall
auto release detection and multi-axis impact detection mechanism,
wherein a plurality of switches are provided in connection with said
microcontroller.
2. A multifunction device as claimed in claim 1, wherein the housing is
made of rugged material provided in the form of a cricket or base ball,
with user replaceable AAA cells and which can be used as a fun device
and multipurpose educational tool.
3. A multifunction device as claimed in any of the preceding claims,
wherein for free fall measurements automatic release detection comprises
of a mechanism such as a 3-axis accelerometer with intelligent data
processing to detect the moment of release of ball in free fall and triggers
the start of digital timer.
4. A multifunction device as claimed in any of the preceding claims,
wherein multi-axis impact detection comprises of a mechanism such as a
3-axis accelerometer with intelligent data processing to detect the
moment of impact whenever the ball hits a surface in any orientation and
triggers the stop of digital timer.
A multifunction device as claimed in any of the preceding claims wherein
the impact detection mechanism comprises a multi-axis switch closure
impact detection device in which each perpendicular axis comprises of a
resilient material (such as spring) with a weight at one end and a nut
fixedly provided at other end with another nut there between through
which the resilient material passes.
6. A multifunction device as claimed in claim 1 or 2, wherein the switches
comprise on/off/reset switch and start/ stop/mode switch.
7. A multifunction device as claimed in any of the preceding claims,
wherein the height of free fall is directly displayed and internally
measured with 1 millimeter resolution and displayed in meters in three
numeric digits with auto ranging decimal in four ranges of .001-.999,
1.00-9.99, 10.0-99.9 and 100-999.
8. A multifunction device as claimed in any of the preceding claims,
wherein the time of free fall is internally measured with 1 millisecond
resolution and displayed in seconds in three numeric digits with autoranging
decimal in four ranges of .OO 1 -.999, 1.00-9.99, 10.0-99.9 and
100-999.
! 9. A multi purpose device as claimed in any of the preceding claims which
measures time with standard stopwatch functionality from milliseconds
to seconds and displays it in four auto ranging modes as in claim 8.
10. A multifunction device as claimed in any of the preceding claims,
wherein the micro controller is connected to a LED/LCD display with
auto-ranging decimal.