A Performance Analysis System for the Sport of Bowling

all of 2 grams or less. Given that a simple plastic case enclosing the module will
contribute an additional 2-3 grams, the total weight of the module with case approximates
the weight of the material removed, resulting in an essentially neutral impact on the
weight and balance of the ball.
2.2.3 Cost
Good bowling balls now cost in excess of $150. A reasonable target retail price for the
SMARTDOT module is approximately one-quarter to one-third of that, or no more than
$50. Assuming normal margins and distribution channels places the target production
cost in the range of $12.50-$15.00. The target production cost determines the means and
methods that can be used to detect the action of the ball (the type and number of sensors),
as well as the technology used to implement the module, i.e., the type of microprocessor
and its on-board resources, the size and type of data memory, the means of
communicating with the outside world, and the costs associated with the battery, case
design, and assembly. The estimated production cost of the SMARTDOT module
prototype is currently $13.50.
2.2.4 Power Consumption
Although the module is readily accessible, battery life must be long enough that the
bowler is not frequently forced to replace the battery. Limiting the energy requirements
of the module extends the battery life, while also limiting the size (height) of the battery,
which is important, since the battery comprises a significant fraction of the height and
weight of the module.
Ideally, the module will spend most of its time in a micro-power standby state. It wakes
up as the bowler releases the ball, monitors and records the output of its sensors while the
ball is rolling down the lane, and then returns to standby mode soon after the ball hits the
pins. The only other time the module should wake up is to upload the sensor data it has
collected to the MASTER application.
Lithium coin cells are the most appropriate battery technology for the module. They are
round (as is the module), light, thin, inexpensive, readily available in standard sizes, and
have a high energy density and cell voltage (3-3.6 volts). The SMARTDOT module
prototype uses two 3-volt BR2016 lithium coin cells, which collectively weigh 3-4 grams
(a little over half of the module's total weight, and contribute a little over one-third
(0.13") to the overall height.
2.2.5 Convenience of Installation and Removal
Since the module has a user-replaceable battery, it must be convenient to install and
remove. By placing the module underneath a removable finger insert, the bowler has
ready access to the module, requiring no special equipment for installation or removal.
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